TY  - JOUR
AU  - Jović, Borka
AU  - Lačnjevac, Uroš
AU  - Jović, Vladimir
AU  - Gajić Krstajić, Ljiljana
AU  - Kovač, Janez
AU  - Poleti, Dejan
AU  - Krstajić, Nedeljko
PY  - 2016
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5833
AB  - The oxygen evolution reaction (OER) was studied at pure Ni and Ni-(Ebonex/Ir) composite coatings in 1 M NaOH solution at 25 °C. Ni-(Ebonex-supported Ir) coatings were electrodeposited from a nickel Watts bath containing different concentrations of suspended Ebonex/Ir particles (0–2 g dm−3) onto a Ni 40 mesh substrate. The surface morphology of the coatings was examined by scanning electron microscopy (SEM), the surface composition by energy dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRPD) and X-ray photoelectron spectroscopy (XPS), whereas the electrochemical properties were studied by electrochemical impedance spectroscopy (EIS), polarization measurements and cyclic voltammetry (CV). It was shown that the roughness factor of Ni-(Ebonex/Ir) composite coatings calculated relative to the surface area of the pure Ni sample increased with the increasing content of Ebonex/Ir particles in the bath to a maximum value of 40.6. All samples displayed a Tafel slope of about 60 mV dec−1 in the potential range corresponding to lower current densities for the OER. The increase of the apparent activity for the OER at Ni-(Ebonex/Ir) coatings compared with the pure Ni coating was attributed only to the increase of the electrochemically active surface area. Although the pure Ni coating initially exhibited higher intrinsic catalytic activity for the OER than the composite coatings, it also showed a drastic loss of activity after subjecting to continuous oxygen evolution at j = 50 mA cm−2 for 24 h (ΔE = 395 mV). At the same time, the OER overpotential at Ni-(Ebonex/Ir) coatings only negligibly increased after the stability test (ΔE = 22 mV). The improved retention of catalytic activity observed with Ni-(Ebonex/Ir) coatings was ascribed to the presence of IrO2, which inhibited the formation of the inactive γ-NiOOH phase.
PB  - Elsevier Ltd.
T2  - International Journal of Hydrogen Energy
T1  - Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part II: Oxygen evolution
EP  - 20514
IS  - 45
SP  - 20502
VL  - 41
DO  - 10.1016/j.ijhydene.2016.08.226
UR  - https://hdl.handle.net/21.15107/rcub_dais_15978
ER  - 

@article{
author = "Jović, Borka and Lačnjevac, Uroš and Jović, Vladimir and Gajić Krstajić, Ljiljana and Kovač, Janez and Poleti, Dejan and Krstajić, Nedeljko",
year = "2016",
abstract = "The oxygen evolution reaction (OER) was studied at pure Ni and Ni-(Ebonex/Ir) composite coatings in 1 M NaOH solution at 25 °C. Ni-(Ebonex-supported Ir) coatings were electrodeposited from a nickel Watts bath containing different concentrations of suspended Ebonex/Ir particles (0–2 g dm−3) onto a Ni 40 mesh substrate. The surface morphology of the coatings was examined by scanning electron microscopy (SEM), the surface composition by energy dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRPD) and X-ray photoelectron spectroscopy (XPS), whereas the electrochemical properties were studied by electrochemical impedance spectroscopy (EIS), polarization measurements and cyclic voltammetry (CV). It was shown that the roughness factor of Ni-(Ebonex/Ir) composite coatings calculated relative to the surface area of the pure Ni sample increased with the increasing content of Ebonex/Ir particles in the bath to a maximum value of 40.6. All samples displayed a Tafel slope of about 60 mV dec−1 in the potential range corresponding to lower current densities for the OER. The increase of the apparent activity for the OER at Ni-(Ebonex/Ir) coatings compared with the pure Ni coating was attributed only to the increase of the electrochemically active surface area. Although the pure Ni coating initially exhibited higher intrinsic catalytic activity for the OER than the composite coatings, it also showed a drastic loss of activity after subjecting to continuous oxygen evolution at j = 50 mA cm−2 for 24 h (ΔE = 395 mV). At the same time, the OER overpotential at Ni-(Ebonex/Ir) coatings only negligibly increased after the stability test (ΔE = 22 mV). The improved retention of catalytic activity observed with Ni-(Ebonex/Ir) coatings was ascribed to the presence of IrO2, which inhibited the formation of the inactive γ-NiOOH phase.",
publisher = "Elsevier Ltd.",
journal = "International Journal of Hydrogen Energy",
title = "Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part II: Oxygen evolution",
pages = "20514-20502",
number = "45",
volume = "41",
doi = "10.1016/j.ijhydene.2016.08.226",
url = "https://hdl.handle.net/21.15107/rcub_dais_15978"
}

Jović, B., Lačnjevac, U., Jović, V., Gajić Krstajić, L., Kovač, J., Poleti, D.,& Krstajić, N.. (2016). Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part II: Oxygen evolution. in International Journal of Hydrogen Energy
Elsevier Ltd.., 41(45), 20502-20514.
https://doi.org/10.1016/j.ijhydene.2016.08.226
https://hdl.handle.net/21.15107/rcub_dais_15978

Jović B, Lačnjevac U, Jović V, Gajić Krstajić L, Kovač J, Poleti D, Krstajić N. Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part II: Oxygen evolution. in International Journal of Hydrogen Energy. 2016;41(45):20502-20514.
doi:10.1016/j.ijhydene.2016.08.226
https://hdl.handle.net/21.15107/rcub_dais_15978 .

Jović, Borka, Lačnjevac, Uroš, Jović, Vladimir, Gajić Krstajić, Ljiljana, Kovač, Janez, Poleti, Dejan, Krstajić, Nedeljko, "Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part II: Oxygen evolution" in International Journal of Hydrogen Energy, 41, no. 45 (2016):20502-20514,
https://doi.org/10.1016/j.ijhydene.2016.08.226 .,
https://hdl.handle.net/21.15107/rcub_dais_15978 .

TY  - JOUR
AU  - Spasojević, M.
AU  - Krstajić, Nedeljko V.
AU  - Spasojević, Pavle
AU  - Ribić-Zelenović, Lenka
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3015
AB  - A mathematical model was set up for anodic, cathodic and overall current efficiencies of an electrochemical cell for hypochlorite production acting as an ideal stirred reactor. A 0.06-0.20 mol dm(-3) NaClO hypochlorite solution was obtained in the cell by the electrolysis of 0.25-0.50 mol dm(-3) sodium chloride solution at a temperature of 20 degrees C, at a current density of 100 mA cm(-2) and at 8.3  lt  pH  lt  8.7. Anodic current losses occur through hypochlorite and water oxidation at the DSA anode, and cathodic current losses result from hypochlorite reduction at the titanium cathode. Theoretical dependences of the anodic current efficiency on the overall anodic current density, hypochlorite concentration and partial current density for water oxidation were established. Theoretically derived relations and the corresponding experimental results showed that oxygen evolution due to water and hypochlorite oxidation leads to reduced thickness of the anodic diffusion layer and increases the limiting diffusion current for hypochlorite oxidation. Mathematical models for the dependence of the cathodic current efficiency on the cathodic current density and hypochlorite concentration in the bulk solution were also established. The expression for the overall current efficiency of the electrochemical cell for hypochlorite production was derived on the basis of both the anodic and the cathodic current efficiency. The good agreement between experimental results and the values provided by the mathematical models has confirmed the correctness of the proposed models, suggesting that the model can be used to optimise electrolysis parameters. (The term hypochlorite is used to include both hypochlorite and undissociated hypochlorous acid.) The concentration of dissolved elementary chlorine in the slightly alkaline environment is negligible compared to hypochlorite concentration.
PB  - Elsevier, Amsterdam
T2  - Chemical Engineering Research & Design
T1  - Modelling current efficiency in an electrochemical hypochlorite reactor
EP  - 601
SP  - 591
VL  - 93
DO  - 10.1016/j.cherd.2014.07.025
ER  - 

@article{
author = "Spasojević, M. and Krstajić, Nedeljko V. and Spasojević, Pavle and Ribić-Zelenović, Lenka",
year = "2015",
abstract = "A mathematical model was set up for anodic, cathodic and overall current efficiencies of an electrochemical cell for hypochlorite production acting as an ideal stirred reactor. A 0.06-0.20 mol dm(-3) NaClO hypochlorite solution was obtained in the cell by the electrolysis of 0.25-0.50 mol dm(-3) sodium chloride solution at a temperature of 20 degrees C, at a current density of 100 mA cm(-2) and at 8.3  lt  pH  lt  8.7. Anodic current losses occur through hypochlorite and water oxidation at the DSA anode, and cathodic current losses result from hypochlorite reduction at the titanium cathode. Theoretical dependences of the anodic current efficiency on the overall anodic current density, hypochlorite concentration and partial current density for water oxidation were established. Theoretically derived relations and the corresponding experimental results showed that oxygen evolution due to water and hypochlorite oxidation leads to reduced thickness of the anodic diffusion layer and increases the limiting diffusion current for hypochlorite oxidation. Mathematical models for the dependence of the cathodic current efficiency on the cathodic current density and hypochlorite concentration in the bulk solution were also established. The expression for the overall current efficiency of the electrochemical cell for hypochlorite production was derived on the basis of both the anodic and the cathodic current efficiency. The good agreement between experimental results and the values provided by the mathematical models has confirmed the correctness of the proposed models, suggesting that the model can be used to optimise electrolysis parameters. (The term hypochlorite is used to include both hypochlorite and undissociated hypochlorous acid.) The concentration of dissolved elementary chlorine in the slightly alkaline environment is negligible compared to hypochlorite concentration.",
publisher = "Elsevier, Amsterdam",
journal = "Chemical Engineering Research & Design",
title = "Modelling current efficiency in an electrochemical hypochlorite reactor",
pages = "601-591",
volume = "93",
doi = "10.1016/j.cherd.2014.07.025"
}

Spasojević, M., Krstajić, N. V., Spasojević, P.,& Ribić-Zelenović, L.. (2015). Modelling current efficiency in an electrochemical hypochlorite reactor. in Chemical Engineering Research & Design
Elsevier, Amsterdam., 93, 591-601.
https://doi.org/10.1016/j.cherd.2014.07.025

Spasojević M, Krstajić NV, Spasojević P, Ribić-Zelenović L. Modelling current efficiency in an electrochemical hypochlorite reactor. in Chemical Engineering Research & Design. 2015;93:591-601.
doi:10.1016/j.cherd.2014.07.025 .

Spasojević, M., Krstajić, Nedeljko V., Spasojević, Pavle, Ribić-Zelenović, Lenka, "Modelling current efficiency in an electrochemical hypochlorite reactor" in Chemical Engineering Research & Design, 93 (2015):591-601,
https://doi.org/10.1016/j.cherd.2014.07.025 . .

TY  - JOUR
AU  - Lačnjevac, Uroš
AU  - Radmilović, Vuk
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko V.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2981
AB  - Nanocomposite cathodes for the hydrogen evolution reaction (HER) were prepared by deposition of RuOx catalyst particles on self-organized titania nanotube (TiNT) arrays of highly developed surface area, following a procedure that involved the initial cathodic intercalation of H+ into the TiNT walls and the subsequent two-step ion-exchange process. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analyses of obtained Ru-TiNT samples revealed that the concentration of RuOx particles in the size range of a few nanometers was the highest at the surface of the TiNT layer and steadily decreased to a minimum value at about 4.5 mu m inside the tubes. The capacitive behavior and electrocatalytic activity for the HER of Ru-TiNT nanocomposites, hydrogenated TiNT samples (H-TiNT) and compact TiO2 were investigated in 1.0 M HClO4 solution at room temperature by means of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Mott-Schottky analysis and steady-state polarization measurements. It was shown that cathodic hydrogenation treatment induced a four orders of magnitude higher concentration of electron donors in TiNT structures providing their quasimetallic behavior in the range of potentials corresponding to the HER. Ru-TiNT cathodes exhibited a more than 250 mV lower overpotential for the HER with respect to bare H-TiNT substrates at the current density of -50 mA cm (2). A decrease of the Tafel slope from about -120 mV/dec for H-TiNT samples to as low as -70 mV/dec for the Ru-TiNT sample with longer tubes was explained by the formal kinetics approach.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Electrochimica Acta
T1  - RuOx nanoparticles deposited on TiO2 nanotube arrays by ion-exchange method as electrocatalysts for the hydrogen evolution reaction in acid solution
EP  - 190
SP  - 178
VL  - 168
DO  - 10.1016/j.electacta.2015.04.012
ER  - 

@article{
author = "Lačnjevac, Uroš and Radmilović, Vuk and Radmilović, Velimir R. and Krstajić, Nedeljko V.",
year = "2015",
abstract = "Nanocomposite cathodes for the hydrogen evolution reaction (HER) were prepared by deposition of RuOx catalyst particles on self-organized titania nanotube (TiNT) arrays of highly developed surface area, following a procedure that involved the initial cathodic intercalation of H+ into the TiNT walls and the subsequent two-step ion-exchange process. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analyses of obtained Ru-TiNT samples revealed that the concentration of RuOx particles in the size range of a few nanometers was the highest at the surface of the TiNT layer and steadily decreased to a minimum value at about 4.5 mu m inside the tubes. The capacitive behavior and electrocatalytic activity for the HER of Ru-TiNT nanocomposites, hydrogenated TiNT samples (H-TiNT) and compact TiO2 were investigated in 1.0 M HClO4 solution at room temperature by means of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Mott-Schottky analysis and steady-state polarization measurements. It was shown that cathodic hydrogenation treatment induced a four orders of magnitude higher concentration of electron donors in TiNT structures providing their quasimetallic behavior in the range of potentials corresponding to the HER. Ru-TiNT cathodes exhibited a more than 250 mV lower overpotential for the HER with respect to bare H-TiNT substrates at the current density of -50 mA cm (2). A decrease of the Tafel slope from about -120 mV/dec for H-TiNT samples to as low as -70 mV/dec for the Ru-TiNT sample with longer tubes was explained by the formal kinetics approach.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Electrochimica Acta",
title = "RuOx nanoparticles deposited on TiO2 nanotube arrays by ion-exchange method as electrocatalysts for the hydrogen evolution reaction in acid solution",
pages = "190-178",
volume = "168",
doi = "10.1016/j.electacta.2015.04.012"
}

Lačnjevac, U., Radmilović, V., Radmilović, V. R.,& Krstajić, N. V.. (2015). RuOx nanoparticles deposited on TiO2 nanotube arrays by ion-exchange method as electrocatalysts for the hydrogen evolution reaction in acid solution. in Electrochimica Acta
Pergamon-Elsevier Science Ltd, Oxford., 168, 178-190.
https://doi.org/10.1016/j.electacta.2015.04.012

Lačnjevac U, Radmilović V, Radmilović VR, Krstajić NV. RuOx nanoparticles deposited on TiO2 nanotube arrays by ion-exchange method as electrocatalysts for the hydrogen evolution reaction in acid solution. in Electrochimica Acta. 2015;168:178-190.
doi:10.1016/j.electacta.2015.04.012 .

Lačnjevac, Uroš, Radmilović, Vuk, Radmilović, Velimir R., Krstajić, Nedeljko V., "RuOx nanoparticles deposited on TiO2 nanotube arrays by ion-exchange method as electrocatalysts for the hydrogen evolution reaction in acid solution" in Electrochimica Acta, 168 (2015):178-190,
https://doi.org/10.1016/j.electacta.2015.04.012 . .

TY  - JOUR
AU  - Elezović, Nevenka
AU  - Radmilović, Velimir R.
AU  - Kovač, Janez
AU  - Babić, Biljana M.
AU  - Gajić Krstajić, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5795
AB  - A platinum nanocatalyst on Sb doped tin oxide support (Sb-SnO2) was synthesized and characterized as a catalyst for oxygen reduction reaction in 0.1 mol dm(-3) NaOH solution at 25 degrees C. Sb (5%) doped tin oxide support was synthesized by a modified hydrazine reduction procedure. The platinum nanocatalyst (20% Pt) on Sb-SnO2 support was synthesized by a borohydride reduction method. The synthesized support and catalyst were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) and X-ray diffraction technique (XRD). X-ray photoelectron spectroscopy was applied to characterize the chemical status of elements before and after Pt-treatment. XPS spectra of Sn 3d, Pt 4f, Sb 3d and O 1s revealed that the Pt-deposition on Sb-SnO2 support induced the reduction of the Sn(4+) oxidation state to Sn(2+) and Sn(0) states, while Pt remained in the metallic state and Sb was in the (3+) oxidation state. Homogenous Pt nanoparticle distribution over the support, without pronounced particle agglomeration, was confirmed by HRTEM technique. The average Pt particle size was 2.9 nm. The electrochemically active Pt surface area of the catalyst was determined by the integration of the cyclic voltammetry curve in the potential region of underpotential deposition of hydrogen, after double layer charge correction, taking into account the reference value of 210 mu C cm(-2) for full monolayer coverage. This calculation gave the value of 51 m(2) g(-1). The kinetics of the oxygen reduction reaction with Pt/[Sb-SnO2 catalyst was studied by cyclic voltammetry and linear sweep voltammetry using a rotating gold disc electrode. Two different Tafel slopes were observed: one close to 60 mV dec(-1) in the low current density region, and another at similar to 120 mV dec(-1) in the higher current densities region, as was already referred in previous reports for the oxygen reduction reaction with polycrystalline Pt, as well as with different Pt based nanocatalysts. The specific activities for oxygen reduction, expressed in terms of kinetic current densities per electrochemically Pt active surface area, as well as per mass of Pt loaded, at the constant potential of practical interest (0.85 V and 0.90 V vs. RHE), were compared to a carbon supported (Vulcan XC-72) catalyst. The Pt/[Sb-SnO2 catalyst exhibited similar catalytic activity for oxygen reduction reaction like carbon supported one. The advantages of the carbon free support application in terms of the durability and stability of the catalysts were proved by accelerated stability tests.
PB  - Royal Society of Chemistry
T2  - RSC Advances
T1  - Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions
EP  - 15929
IS  - 21
SP  - 15923
VL  - 5
DO  - 10.1039/c4ra13391a
UR  - https://hdl.handle.net/21.15107/rcub_dais_3354
ER  - 

@article{
author = "Elezović, Nevenka and Radmilović, Velimir R. and Kovač, Janez and Babić, Biljana M. and Gajić Krstajić, Ljiljana and Krstajić, Nedeljko",
year = "2015",
abstract = "A platinum nanocatalyst on Sb doped tin oxide support (Sb-SnO2) was synthesized and characterized as a catalyst for oxygen reduction reaction in 0.1 mol dm(-3) NaOH solution at 25 degrees C. Sb (5%) doped tin oxide support was synthesized by a modified hydrazine reduction procedure. The platinum nanocatalyst (20% Pt) on Sb-SnO2 support was synthesized by a borohydride reduction method. The synthesized support and catalyst were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) and X-ray diffraction technique (XRD). X-ray photoelectron spectroscopy was applied to characterize the chemical status of elements before and after Pt-treatment. XPS spectra of Sn 3d, Pt 4f, Sb 3d and O 1s revealed that the Pt-deposition on Sb-SnO2 support induced the reduction of the Sn(4+) oxidation state to Sn(2+) and Sn(0) states, while Pt remained in the metallic state and Sb was in the (3+) oxidation state. Homogenous Pt nanoparticle distribution over the support, without pronounced particle agglomeration, was confirmed by HRTEM technique. The average Pt particle size was 2.9 nm. The electrochemically active Pt surface area of the catalyst was determined by the integration of the cyclic voltammetry curve in the potential region of underpotential deposition of hydrogen, after double layer charge correction, taking into account the reference value of 210 mu C cm(-2) for full monolayer coverage. This calculation gave the value of 51 m(2) g(-1). The kinetics of the oxygen reduction reaction with Pt/[Sb-SnO2 catalyst was studied by cyclic voltammetry and linear sweep voltammetry using a rotating gold disc electrode. Two different Tafel slopes were observed: one close to 60 mV dec(-1) in the low current density region, and another at similar to 120 mV dec(-1) in the higher current densities region, as was already referred in previous reports for the oxygen reduction reaction with polycrystalline Pt, as well as with different Pt based nanocatalysts. The specific activities for oxygen reduction, expressed in terms of kinetic current densities per electrochemically Pt active surface area, as well as per mass of Pt loaded, at the constant potential of practical interest (0.85 V and 0.90 V vs. RHE), were compared to a carbon supported (Vulcan XC-72) catalyst. The Pt/[Sb-SnO2 catalyst exhibited similar catalytic activity for oxygen reduction reaction like carbon supported one. The advantages of the carbon free support application in terms of the durability and stability of the catalysts were proved by accelerated stability tests.",
publisher = "Royal Society of Chemistry",
journal = "RSC Advances",
title = "Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions",
pages = "15929-15923",
number = "21",
volume = "5",
doi = "10.1039/c4ra13391a",
url = "https://hdl.handle.net/21.15107/rcub_dais_3354"
}

Elezović, N., Radmilović, V. R., Kovač, J., Babić, B. M., Gajić Krstajić, L.,& Krstajić, N.. (2015). Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions. in RSC Advances
Royal Society of Chemistry., 5(21), 15923-15929.
https://doi.org/10.1039/c4ra13391a
https://hdl.handle.net/21.15107/rcub_dais_3354

Elezović N, Radmilović VR, Kovač J, Babić BM, Gajić Krstajić L, Krstajić N. Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions. in RSC Advances. 2015;5(21):15923-15929.
doi:10.1039/c4ra13391a
https://hdl.handle.net/21.15107/rcub_dais_3354 .

Elezović, Nevenka, Radmilović, Velimir R., Kovač, Janez, Babić, Biljana M., Gajić Krstajić, Ljiljana, Krstajić, Nedeljko, "Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions" in RSC Advances, 5, no. 21 (2015):15923-15929,
https://doi.org/10.1039/c4ra13391a .,
https://hdl.handle.net/21.15107/rcub_dais_3354 .

TY  - JOUR
AU  - Obradović, Maja
AU  - Lačnjevac, Uroš
AU  - Babić, Biljana M.
AU  - Ercius, P.
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko V.
AU  - Gojković, Snežana Lj.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2978
AB  - Two binary Ru-Ti oxides, Rum Ti0.9O2 and Ru0.7Ti0.3O2, were synthesized by the sol-gel method and used as an electrocatalyst support. The system was characterized by XRD, EDS, TEM and cyclic voltammetry. The Rum Ti0.9O2 and Ru0.7Ti0.3O2 consist of two phases of anatase and rutile structure. An average size of the Pt nanoparticles supported on them is similar to 3.5 nm and they are deposited on both Ru and Ti-rich domains. The supports exhibited good conductivity and electrochemical stability. The onset potentials of COads oxidation on the synthesized catalysts and on commercial PtRu/C are similar to each other and lower than that on Pt/C. This suggests that in Pt/Rum Ti0.9O2 and Pt/Ru0(.7)Ti(0.3)O(2) the Pt nanoparticles are in close contact with Ru atoms from the support, which enables the bifunctional mechanism. The activity and stability of the catalysts for methanol oxidation were examined under potentiodynamic and potentiostatic conditions. While the activity of Pt/Rum Ti0.9O2 is unsatisfactory, the performance of Pt/Ru0.7Ti0.3O2 is comparable to PtRu/C. For example, in the potentiostatic test at 0.5 V the activities after 25 min are 0.035 mA cm(-2) and 0.022 mA cm(-2) for Pt/Ru0.7Ti0.3O2 and PtRu/C, respectively. In potentiodynamic test the activities at 0.5V after 250 cycles are around 0.02 mA cm(-2) for both catalysts.
PB  - Elsevier, Amsterdam
T2  - Applied Catalysis B-Environmental
T1  - RuxTi1-xO2 as the support for Pt nanoparticles: Electrocatalysis of methanol oxidation
EP  - 152
SP  - 144
VL  - 170
DO  - 10.1016/j.apcatb.2015.01.038
ER  - 

@article{
author = "Obradović, Maja and Lačnjevac, Uroš and Babić, Biljana M. and Ercius, P. and Radmilović, Velimir R. and Krstajić, Nedeljko V. and Gojković, Snežana Lj.",
year = "2015",
abstract = "Two binary Ru-Ti oxides, Rum Ti0.9O2 and Ru0.7Ti0.3O2, were synthesized by the sol-gel method and used as an electrocatalyst support. The system was characterized by XRD, EDS, TEM and cyclic voltammetry. The Rum Ti0.9O2 and Ru0.7Ti0.3O2 consist of two phases of anatase and rutile structure. An average size of the Pt nanoparticles supported on them is similar to 3.5 nm and they are deposited on both Ru and Ti-rich domains. The supports exhibited good conductivity and electrochemical stability. The onset potentials of COads oxidation on the synthesized catalysts and on commercial PtRu/C are similar to each other and lower than that on Pt/C. This suggests that in Pt/Rum Ti0.9O2 and Pt/Ru0(.7)Ti(0.3)O(2) the Pt nanoparticles are in close contact with Ru atoms from the support, which enables the bifunctional mechanism. The activity and stability of the catalysts for methanol oxidation were examined under potentiodynamic and potentiostatic conditions. While the activity of Pt/Rum Ti0.9O2 is unsatisfactory, the performance of Pt/Ru0.7Ti0.3O2 is comparable to PtRu/C. For example, in the potentiostatic test at 0.5 V the activities after 25 min are 0.035 mA cm(-2) and 0.022 mA cm(-2) for Pt/Ru0.7Ti0.3O2 and PtRu/C, respectively. In potentiodynamic test the activities at 0.5V after 250 cycles are around 0.02 mA cm(-2) for both catalysts.",
publisher = "Elsevier, Amsterdam",
journal = "Applied Catalysis B-Environmental",
title = "RuxTi1-xO2 as the support for Pt nanoparticles: Electrocatalysis of methanol oxidation",
pages = "152-144",
volume = "170",
doi = "10.1016/j.apcatb.2015.01.038"
}

Obradović, M., Lačnjevac, U., Babić, B. M., Ercius, P., Radmilović, V. R., Krstajić, N. V.,& Gojković, S. Lj.. (2015). RuxTi1-xO2 as the support for Pt nanoparticles: Electrocatalysis of methanol oxidation. in Applied Catalysis B-Environmental
Elsevier, Amsterdam., 170, 144-152.
https://doi.org/10.1016/j.apcatb.2015.01.038

Obradović M, Lačnjevac U, Babić BM, Ercius P, Radmilović VR, Krstajić NV, Gojković SL. RuxTi1-xO2 as the support for Pt nanoparticles: Electrocatalysis of methanol oxidation. in Applied Catalysis B-Environmental. 2015;170:144-152.
doi:10.1016/j.apcatb.2015.01.038 .

Obradović, Maja, Lačnjevac, Uroš, Babić, Biljana M., Ercius, P., Radmilović, Velimir R., Krstajić, Nedeljko V., Gojković, Snežana Lj., "RuxTi1-xO2 as the support for Pt nanoparticles: Electrocatalysis of methanol oxidation" in Applied Catalysis B-Environmental, 170 (2015):144-152,
https://doi.org/10.1016/j.apcatb.2015.01.038 . .

TY  - JOUR
AU  - Jović, Borka
AU  - Jović, Vladimir
AU  - Lačnjevac, Uroš
AU  - Gajić Krstajić, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5793
AB  - The hydrogen evolution reaction (HER) was studied at electrodeposited Ni and Ni-(Ebonex/Ir) composite coatings in 1 mol dm-3 NaOH solution at 25 °C. The Ni-(Ebonex/Ir) coatings were electrodeposited from a nickel Watts type bath containing different amounts of suspended Ebonex/Ir(30 wt.%) powder particles (0-2 g dm-3) onto a Ni 40 mesh substrate. The electrodes were investigated by cyclic voltammetry (CV), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), electrochemical impedance spectroscopy (EIS) and polarization measurements. It was shown that the roughness factor of coatings increased to a maximum value of 27 with increasing the concentration of Ebonex/Ir particles in the deposition bath, while that of a pure Ni coating was found to be 3.2. In the whole potential range of the HER only one Tafel slope of about -120 mV dec-1 was observed at all polarization curves. Considerably improved intrinsic catalytic activity for the HER compared to pure Ni was achieved with the composite coating deposited from the bath with the lowest concentration of Ebonex/Ir particles (0.1 g dm-3). Further enhancement of the apparent catalytic activity for the HER of Ni-(Ebonex/Ir) composite coatings obtained at higher concentrations of suspended Ebonex/Ir particles in the bath was attributed only to the increase of their electrochemically active surface area. © 2015 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
PB  - Elsevier
T2  - International Journal of Hydrogen Energy
T1  - Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part I: Hydrogen evolution
EP  - 10490
IS  - 33
SP  - 10480
VL  - 40
DO  - 10.1016/j.ijhydene.2015.06.127
UR  - https://hdl.handle.net/21.15107/rcub_dais_3530
ER  - 

@article{
author = "Jović, Borka and Jović, Vladimir and Lačnjevac, Uroš and Gajić Krstajić, Ljiljana and Krstajić, Nedeljko",
year = "2015",
abstract = "The hydrogen evolution reaction (HER) was studied at electrodeposited Ni and Ni-(Ebonex/Ir) composite coatings in 1 mol dm-3 NaOH solution at 25 °C. The Ni-(Ebonex/Ir) coatings were electrodeposited from a nickel Watts type bath containing different amounts of suspended Ebonex/Ir(30 wt.%) powder particles (0-2 g dm-3) onto a Ni 40 mesh substrate. The electrodes were investigated by cyclic voltammetry (CV), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), electrochemical impedance spectroscopy (EIS) and polarization measurements. It was shown that the roughness factor of coatings increased to a maximum value of 27 with increasing the concentration of Ebonex/Ir particles in the deposition bath, while that of a pure Ni coating was found to be 3.2. In the whole potential range of the HER only one Tafel slope of about -120 mV dec-1 was observed at all polarization curves. Considerably improved intrinsic catalytic activity for the HER compared to pure Ni was achieved with the composite coating deposited from the bath with the lowest concentration of Ebonex/Ir particles (0.1 g dm-3). Further enhancement of the apparent catalytic activity for the HER of Ni-(Ebonex/Ir) composite coatings obtained at higher concentrations of suspended Ebonex/Ir particles in the bath was attributed only to the increase of their electrochemically active surface area. © 2015 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.",
publisher = "Elsevier",
journal = "International Journal of Hydrogen Energy",
title = "Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part I: Hydrogen evolution",
pages = "10490-10480",
number = "33",
volume = "40",
doi = "10.1016/j.ijhydene.2015.06.127",
url = "https://hdl.handle.net/21.15107/rcub_dais_3530"
}

Jović, B., Jović, V., Lačnjevac, U., Gajić Krstajić, L.,& Krstajić, N.. (2015). Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part I: Hydrogen evolution. in International Journal of Hydrogen Energy
Elsevier., 40(33), 10480-10490.
https://doi.org/10.1016/j.ijhydene.2015.06.127
https://hdl.handle.net/21.15107/rcub_dais_3530

Jović B, Jović V, Lačnjevac U, Gajić Krstajić L, Krstajić N. Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part I: Hydrogen evolution. in International Journal of Hydrogen Energy. 2015;40(33):10480-10490.
doi:10.1016/j.ijhydene.2015.06.127
https://hdl.handle.net/21.15107/rcub_dais_3530 .

Jović, Borka, Jović, Vladimir, Lačnjevac, Uroš, Gajić Krstajić, Ljiljana, Krstajić, Nedeljko, "Ni-(Ebonex-supported Ir) composite coatings as electrocatalysts for alkaline water electrolysis. Part I: Hydrogen evolution" in International Journal of Hydrogen Energy, 40, no. 33 (2015):10480-10490,
https://doi.org/10.1016/j.ijhydene.2015.06.127 .,
https://hdl.handle.net/21.15107/rcub_dais_3530 .

TY  - JOUR
AU  - Lačnjevac, Uroš
AU  - Jović, Borka
AU  - Gajić Krstajić, Ljiljana
AU  - Kovač, Janez
AU  - Jović, Vladimir
AU  - Krstajić, Nedeljko
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5725
AB  - The aim of this work was to investigate the possibility of preparation of the composite Cr–MoO2 coatings onto steel and titanium substrates as cathode materials with high selective properties which imply the suppression of hypochlorite reduction as a side reaction during hypochlorite commercial production. The electrodes were prepared by simultaneous deposition of chromium and suspended MoO2 particles on titanium substrate from acid chromium (VI) bath. The current efficiency for electrodeposition of the composite coatings did not vary significantly with the concentration of suspended MoO2 particles. The content of molybdenum in the deposits was relatively low (0.2–1.5 at.%) and increased with increasing the concentration of suspended MoO2 particles in the bath, in the range from 0 to 10 g dm−3. With further increase in the concentration of MoO2, the content of molybdenum in the coating varied insignificantly.X-ray photoelectron spectroscopy-XPS and EDS analysis were applied to analyze elemental composition and chemical bonding of elements on the surface and in the sub-surface region of obtained coatings. When the concentration of MoO2 particles in the bath was raised above 5 g dm−3, the appearance of the coating changed from the typical pure chromium deposit to needle-like deposit with the appearance of black inclusions on the surface. XPS analysis and corresponding Cr 2p spectra showed the presence of chromium oxide, probably Cr2O3 with Cr(3+) valence state on the surface and in the sub-surface region of Cr–MoO2 coatings.Investigation of the current efficiency for the hydrogen evolution reaction (HER) on Cr–MoO2 cathodes showed that it increased with the increase of the content of MoO2 particles in the coating, exceeding the value of 97% in the solution with the hypochlorite concentration of 0.21 mol dm−3. Under the same conditions, the current efficiency for the HER on Ti and Ti/Cr cathodes is very low (≈20%), and corresponding polarization curves confirmed the fact that the side reaction of hypochlorite reduction takes place in the diffusion-controlled regime on these electrodes. The high selectivity of Cr–MoO2 coating is probably caused by the presence of chromium oxide (hydroxide) formed at the surface of the coating during co-deposition of Cr and MoO2 particles, which prevents hypochlorite reduction on the cathode during the HER.
PB  - Elsevier
T2  - Electrochimica Acta
T1  - Ti substrate coated with composite Cr–MoO2 coatings as highly selective cathode materials in hypochlorite production
EP  - 42
SP  - 34
VL  - 96
DO  - 10.1016/j.electacta.2013.02.086
UR  - https://hdl.handle.net/21.15107/rcub_dais_358
ER  - 

@article{
author = "Lačnjevac, Uroš and Jović, Borka and Gajić Krstajić, Ljiljana and Kovač, Janez and Jović, Vladimir and Krstajić, Nedeljko",
year = "2013",
abstract = "The aim of this work was to investigate the possibility of preparation of the composite Cr–MoO2 coatings onto steel and titanium substrates as cathode materials with high selective properties which imply the suppression of hypochlorite reduction as a side reaction during hypochlorite commercial production. The electrodes were prepared by simultaneous deposition of chromium and suspended MoO2 particles on titanium substrate from acid chromium (VI) bath. The current efficiency for electrodeposition of the composite coatings did not vary significantly with the concentration of suspended MoO2 particles. The content of molybdenum in the deposits was relatively low (0.2–1.5 at.%) and increased with increasing the concentration of suspended MoO2 particles in the bath, in the range from 0 to 10 g dm−3. With further increase in the concentration of MoO2, the content of molybdenum in the coating varied insignificantly.X-ray photoelectron spectroscopy-XPS and EDS analysis were applied to analyze elemental composition and chemical bonding of elements on the surface and in the sub-surface region of obtained coatings. When the concentration of MoO2 particles in the bath was raised above 5 g dm−3, the appearance of the coating changed from the typical pure chromium deposit to needle-like deposit with the appearance of black inclusions on the surface. XPS analysis and corresponding Cr 2p spectra showed the presence of chromium oxide, probably Cr2O3 with Cr(3+) valence state on the surface and in the sub-surface region of Cr–MoO2 coatings.Investigation of the current efficiency for the hydrogen evolution reaction (HER) on Cr–MoO2 cathodes showed that it increased with the increase of the content of MoO2 particles in the coating, exceeding the value of 97% in the solution with the hypochlorite concentration of 0.21 mol dm−3. Under the same conditions, the current efficiency for the HER on Ti and Ti/Cr cathodes is very low (≈20%), and corresponding polarization curves confirmed the fact that the side reaction of hypochlorite reduction takes place in the diffusion-controlled regime on these electrodes. The high selectivity of Cr–MoO2 coating is probably caused by the presence of chromium oxide (hydroxide) formed at the surface of the coating during co-deposition of Cr and MoO2 particles, which prevents hypochlorite reduction on the cathode during the HER.",
publisher = "Elsevier",
journal = "Electrochimica Acta",
title = "Ti substrate coated with composite Cr–MoO2 coatings as highly selective cathode materials in hypochlorite production",
pages = "42-34",
volume = "96",
doi = "10.1016/j.electacta.2013.02.086",
url = "https://hdl.handle.net/21.15107/rcub_dais_358"
}

Lačnjevac, U., Jović, B., Gajić Krstajić, L., Kovač, J., Jović, V.,& Krstajić, N.. (2013). Ti substrate coated with composite Cr–MoO2 coatings as highly selective cathode materials in hypochlorite production. in Electrochimica Acta
Elsevier., 96, 34-42.
https://doi.org/10.1016/j.electacta.2013.02.086
https://hdl.handle.net/21.15107/rcub_dais_358

Lačnjevac U, Jović B, Gajić Krstajić L, Kovač J, Jović V, Krstajić N. Ti substrate coated with composite Cr–MoO2 coatings as highly selective cathode materials in hypochlorite production. in Electrochimica Acta. 2013;96:34-42.
doi:10.1016/j.electacta.2013.02.086
https://hdl.handle.net/21.15107/rcub_dais_358 .

Lačnjevac, Uroš, Jović, Borka, Gajić Krstajić, Ljiljana, Kovač, Janez, Jović, Vladimir, Krstajić, Nedeljko, "Ti substrate coated with composite Cr–MoO2 coatings as highly selective cathode materials in hypochlorite production" in Electrochimica Acta, 96 (2013):34-42,
https://doi.org/10.1016/j.electacta.2013.02.086 .,
https://hdl.handle.net/21.15107/rcub_dais_358 .

TY  - JOUR
AU  - Krstajić, Mila
AU  - Obradović, Maja
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
AU  - Lačnjevac, Uroš
AU  - Krstajić, Nedeljko V.
AU  - Gojković, Snežana Lj.
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2353
AB  - Ru-doped SnO2 powder, (RuxSn1-x)O2, with a Sn:Ru atomic ratio of 9:1 was synthesized and used as a support for Pt nanoparticles (30 mass % loading). The (RuxSn1-x)O2 support and the Pt/(RuxSn1-x)O2 catalyst were characterized by X-ray diffraction measurements, energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM). The (RuxSn1-x)O2 was found to be a two-phase material consisting of probably a solid solution of RuO2 in SnO2 and pure RuO2. The average Pt particle size determined by TEM was 5.3 nm. Cyclic voltammetry of Pt/(RuxSn1-x)O2 indicated good conductivity of the support and displayed the usual features of Pt. The results of the electrochemical oxidation of COads and methanol on Pt/(RuxSn1-x)O2 were compared with those on commercial Pt/C and PtRu/C catalysts. Oxidation of COads on Pt/(RuxSn1-x)O2 starts at lower positive potentials than on PtRu/C and Pt/C. Potentiodynamic polarization curves and chronoamperometric curves of methanol oxidation indicated higher initial activity of the Pt/(RuxSn1-x)O2 catalyst compared to PtRu/C, but also a greater loss in current density over time. A potentiodynamic stability test of the catalysts revealed that deactivation of Pt/(RuxSn1-x)O2 and Pt/C was primarily caused by poisoning of the Pt surface by residues of methanol oxidation, which mostly occurred during the first potential cycle. In the case of PtRu/C, the poisoning of the surface was minor and deactivation was caused by surface area loss of the PtRu.
AB  - Sintetizovan je prah SnO2 dopovan rutenijumom, (RuxSn1-x)O2, sa atomskim odnosom Sn:Ru od 9:1, i korišćen kao nosač nanočestica platine. Udeo Pt u dobijenom katalizatoru, Pt/(RuxSn1-x)O2, bio je 30 mas. %. Nosač i katalizator su karakterisani difrakcijom X-zraka, energetski disperzivnom spektroskopijom X-zraka i transmisionom elektronskom mikroskopijom (TEM). Pokazano je da je (RuxSn1-x)O2 dvofazni materijal koji verovatno sadrži čvrst rastvor RuO2 u SnO2 i čist RuO2. Prosečna veličina zrna Pt, određena TEM analizom, iznosi 5,3 nm. Ciklična voltametrija Pt/(RuxSn1-x)O2 ukazala je na dobru provodnost nosača katalizatora i na uobičajene karakteristike Pt. Upoređeni su rezultati elektrohemijske oksidacije COads na Pt/(RuxSn1-x)O2, Pt/C i PtRu/C. Oksidacija COads na Pt/(RuxSn1-x)O2 počinje na negativnijim potencijalima u odnosu na PtRu/C i Pt/C. Potenciodinamičke polarizacione krive i hronoamperometrijske krive za oksidaciju metanola ukazuju na veću početnu aktivnost katalizatora Pt/(RuxSn1-x)O2 u odnosu na PtRu/C, ali i na veće smanjenje gustine struje tokom vremena. Test potenciodinamičke stabilnosti katalizatora je ukazao da je smanjenje aktivnosti Pt/(RuxSn1-x)O2 i Pt/C prvenstveno prouzrokovano trovanjem površine Pt proizvodima nepotpune oksidacije metanola, koje se uglavnom odigrava tokom prvog ciklusa. Kod PtRu/C trovanje površine je minimalno, a smanjenje aktivnosti je prouzrokovano smanjenjem elektrohemijski aktivne površine PtRu.
PB  - Serbian Chemical Society, Belgrade
T2  - Journal of the Serbian Chemical Society
T1  - Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst
T1  - Elektrohemijska oksidacija metanola na katalizatoru Pt/(RuxSn1-x)O2
EP  - 1716
IS  - 11
SP  - 1703
VL  - 78
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2353
ER  - 

@article{
author = "Krstajić, Mila and Obradović, Maja and Babić, Biljana M. and Radmilović, Velimir R. and Lačnjevac, Uroš and Krstajić, Nedeljko V. and Gojković, Snežana Lj.",
year = "2013",
abstract = "Ru-doped SnO2 powder, (RuxSn1-x)O2, with a Sn:Ru atomic ratio of 9:1 was synthesized and used as a support for Pt nanoparticles (30 mass % loading). The (RuxSn1-x)O2 support and the Pt/(RuxSn1-x)O2 catalyst were characterized by X-ray diffraction measurements, energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM). The (RuxSn1-x)O2 was found to be a two-phase material consisting of probably a solid solution of RuO2 in SnO2 and pure RuO2. The average Pt particle size determined by TEM was 5.3 nm. Cyclic voltammetry of Pt/(RuxSn1-x)O2 indicated good conductivity of the support and displayed the usual features of Pt. The results of the electrochemical oxidation of COads and methanol on Pt/(RuxSn1-x)O2 were compared with those on commercial Pt/C and PtRu/C catalysts. Oxidation of COads on Pt/(RuxSn1-x)O2 starts at lower positive potentials than on PtRu/C and Pt/C. Potentiodynamic polarization curves and chronoamperometric curves of methanol oxidation indicated higher initial activity of the Pt/(RuxSn1-x)O2 catalyst compared to PtRu/C, but also a greater loss in current density over time. A potentiodynamic stability test of the catalysts revealed that deactivation of Pt/(RuxSn1-x)O2 and Pt/C was primarily caused by poisoning of the Pt surface by residues of methanol oxidation, which mostly occurred during the first potential cycle. In the case of PtRu/C, the poisoning of the surface was minor and deactivation was caused by surface area loss of the PtRu., Sintetizovan je prah SnO2 dopovan rutenijumom, (RuxSn1-x)O2, sa atomskim odnosom Sn:Ru od 9:1, i korišćen kao nosač nanočestica platine. Udeo Pt u dobijenom katalizatoru, Pt/(RuxSn1-x)O2, bio je 30 mas. %. Nosač i katalizator su karakterisani difrakcijom X-zraka, energetski disperzivnom spektroskopijom X-zraka i transmisionom elektronskom mikroskopijom (TEM). Pokazano je da je (RuxSn1-x)O2 dvofazni materijal koji verovatno sadrži čvrst rastvor RuO2 u SnO2 i čist RuO2. Prosečna veličina zrna Pt, određena TEM analizom, iznosi 5,3 nm. Ciklična voltametrija Pt/(RuxSn1-x)O2 ukazala je na dobru provodnost nosača katalizatora i na uobičajene karakteristike Pt. Upoređeni su rezultati elektrohemijske oksidacije COads na Pt/(RuxSn1-x)O2, Pt/C i PtRu/C. Oksidacija COads na Pt/(RuxSn1-x)O2 počinje na negativnijim potencijalima u odnosu na PtRu/C i Pt/C. Potenciodinamičke polarizacione krive i hronoamperometrijske krive za oksidaciju metanola ukazuju na veću početnu aktivnost katalizatora Pt/(RuxSn1-x)O2 u odnosu na PtRu/C, ali i na veće smanjenje gustine struje tokom vremena. Test potenciodinamičke stabilnosti katalizatora je ukazao da je smanjenje aktivnosti Pt/(RuxSn1-x)O2 i Pt/C prvenstveno prouzrokovano trovanjem površine Pt proizvodima nepotpune oksidacije metanola, koje se uglavnom odigrava tokom prvog ciklusa. Kod PtRu/C trovanje površine je minimalno, a smanjenje aktivnosti je prouzrokovano smanjenjem elektrohemijski aktivne površine PtRu.",
publisher = "Serbian Chemical Society, Belgrade",
journal = "Journal of the Serbian Chemical Society",
title = "Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst, Elektrohemijska oksidacija metanola na katalizatoru Pt/(RuxSn1-x)O2",
pages = "1716-1703",
number = "11",
volume = "78",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2353"
}

Krstajić, M., Obradović, M., Babić, B. M., Radmilović, V. R., Lačnjevac, U., Krstajić, N. V.,& Gojković, S. Lj.. (2013). Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst. in Journal of the Serbian Chemical Society
Serbian Chemical Society, Belgrade., 78(11), 1703-1716.
https://hdl.handle.net/21.15107/rcub_technorep_2353

Krstajić M, Obradović M, Babić BM, Radmilović VR, Lačnjevac U, Krstajić NV, Gojković SL. Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst. in Journal of the Serbian Chemical Society. 2013;78(11):1703-1716.
https://hdl.handle.net/21.15107/rcub_technorep_2353 .

Krstajić, Mila, Obradović, Maja, Babić, Biljana M., Radmilović, Velimir R., Lačnjevac, Uroš, Krstajić, Nedeljko V., Gojković, Snežana Lj., "Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst" in Journal of the Serbian Chemical Society, 78, no. 11 (2013):1703-1716,
https://hdl.handle.net/21.15107/rcub_technorep_2353 .

TY  - JOUR
AU  - Obradović, Maja
AU  - Babić, Biljana M.
AU  - Krstajić, Nedeljko V.
AU  - Gojković, Snežana Lj.
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2369
AB  - Tungsten carbide was synthesized by calcination of carbon cryogel with embedded tungsten in a form of metatungstate. This material was used as a support for Pt nanoparticles. XRD pattern of W-C support indicated the presence of WC, W2C, and unreacted W, as well as graphitized carbon. According to previous TEM analysis of W-C support, it contains particles with core-shell structure, where the W particle was covered with the shell of a mixture of WC and W2C. The average Pt grain size calculated from XRD pattern was about 6 nm. A cyclic voltammogram of W-C support was recorded within the potential range relevant for its application as a catalyst support in fuel cells. The pair of anodic/cathodic peaks close to the negative potential limit could be ascribed to the intercalation of hydrogen within hydrous tungsten oxide, which is always present on the surface of WC in aqueous solutions. The cyclic voltammogram of Pt/W-C indicated that tungsten oxide species are present on tungsten carbide shell as well as on the surface of Pt nanoparticles. The Pt surface is only partially covered by hydrous tungsten oxide. Hydrogen intercalation in hydrous tungsten oxide is enhanced in the presence of Pt nanoparticles. Also, the presence of hydrated tungsten oxide leads to the decrease of OH chemisorbed on Pt surface. Stripping of underpotentially deposited copper was used for the assessment of Pt surface area and the specific surface area of Pt was estimated to be 41 m2 g-1. The electrochemical oxygen reduction reaction was examined on the synthesized Pt/W-C catalyst and compared with the results on the commercial Pt/C catalyst. It was found that the current densities at Pt/W-C were almost twice as high as those on Pt/C. The Tafel plots for both catalysts are characterized with two Tafel slopes: -0.060 V dec-1 at low current densities, and -0.120 V dec-1 at high current densities. From the rotational dependence of the reaction rate, it was found that oxygen reduction on both Pt/W-C and Pt/C follows the first order kinetics with respect to O2 and that four electrons are transferred per O2 molecule. The results show that the presence of tungsten carbide in support material, i.e. hydrous tungsten oxide on Pt surface, leads to promotion of oxygen reduction on the Pt/W-C catalyst. It was assumed that oxophilic hydrated tungsten oxide hinders OH adsorption on Pt surface, thus increasing Pt surface area available for O2 adsorption and its electrochemical reduction.
AB  - Sintetizovan je nosač katalizatora u kojem se na ugljeničnoj osnovi nalaze nanočestice metalnog volframa obavijene volfram-karbidom i na njega su nanete nanočestice Pt. Karakterizacija sintetizovanog uzorka cikličnom voltametrijom u kiseloj sredini ukazala je na oksidaciju volframovih vrsta iz nosača i formiranje hidratisanih oksidnih vrsta volframa na površini Pt. Elektrohemijska redukcija O2 u kiseloj sredini je ispitivana na sintetizovanom uzorku i rezultati su upoređeni sa komercijalnim katalizatorom u kojem su nanočestice Pt na nosaču od ugljenika razvijene površine. Pokazano je da redukcija O2, bez obzira na nosač katalizatora, sledi kinetiku prvog reda po O2 uz razmenu četiri elektrona, ali da su gustine struje veće u slučaju nosača sa volfram-karbidom. Povećana aktivnost sintetizovanog katalizatora je posledica prisustva oksofiličnih hidratisanih oksida volframa koji sprečavaju adsorpciju hidratisanog oksida na površini Pt i tako povećavaju površinu Pt dostupnu za adsorpciju i redukciju molekula kiseonika.
PB  - Association of Chemical Engineers of Serbia
T2  - Hemijska industrija
T1  - Effect of tungsten carbide in carbon Pt catalyst support on electrochemical oxygen reduction in acid solution
T1  - Uticaj prisustva volfram-karbida u ugljeničnom nosaču Pt nanočestica na elektrohemijsku redukciju kiseonika u kiselom rastvoru
EP  - 311
IS  - 2
SP  - 303
VL  - 67
DO  - 10.2298/HEMIND120307063O
ER  - 

@article{
author = "Obradović, Maja and Babić, Biljana M. and Krstajić, Nedeljko V. and Gojković, Snežana Lj.",
year = "2013",
abstract = "Tungsten carbide was synthesized by calcination of carbon cryogel with embedded tungsten in a form of metatungstate. This material was used as a support for Pt nanoparticles. XRD pattern of W-C support indicated the presence of WC, W2C, and unreacted W, as well as graphitized carbon. According to previous TEM analysis of W-C support, it contains particles with core-shell structure, where the W particle was covered with the shell of a mixture of WC and W2C. The average Pt grain size calculated from XRD pattern was about 6 nm. A cyclic voltammogram of W-C support was recorded within the potential range relevant for its application as a catalyst support in fuel cells. The pair of anodic/cathodic peaks close to the negative potential limit could be ascribed to the intercalation of hydrogen within hydrous tungsten oxide, which is always present on the surface of WC in aqueous solutions. The cyclic voltammogram of Pt/W-C indicated that tungsten oxide species are present on tungsten carbide shell as well as on the surface of Pt nanoparticles. The Pt surface is only partially covered by hydrous tungsten oxide. Hydrogen intercalation in hydrous tungsten oxide is enhanced in the presence of Pt nanoparticles. Also, the presence of hydrated tungsten oxide leads to the decrease of OH chemisorbed on Pt surface. Stripping of underpotentially deposited copper was used for the assessment of Pt surface area and the specific surface area of Pt was estimated to be 41 m2 g-1. The electrochemical oxygen reduction reaction was examined on the synthesized Pt/W-C catalyst and compared with the results on the commercial Pt/C catalyst. It was found that the current densities at Pt/W-C were almost twice as high as those on Pt/C. The Tafel plots for both catalysts are characterized with two Tafel slopes: -0.060 V dec-1 at low current densities, and -0.120 V dec-1 at high current densities. From the rotational dependence of the reaction rate, it was found that oxygen reduction on both Pt/W-C and Pt/C follows the first order kinetics with respect to O2 and that four electrons are transferred per O2 molecule. The results show that the presence of tungsten carbide in support material, i.e. hydrous tungsten oxide on Pt surface, leads to promotion of oxygen reduction on the Pt/W-C catalyst. It was assumed that oxophilic hydrated tungsten oxide hinders OH adsorption on Pt surface, thus increasing Pt surface area available for O2 adsorption and its electrochemical reduction., Sintetizovan je nosač katalizatora u kojem se na ugljeničnoj osnovi nalaze nanočestice metalnog volframa obavijene volfram-karbidom i na njega su nanete nanočestice Pt. Karakterizacija sintetizovanog uzorka cikličnom voltametrijom u kiseloj sredini ukazala je na oksidaciju volframovih vrsta iz nosača i formiranje hidratisanih oksidnih vrsta volframa na površini Pt. Elektrohemijska redukcija O2 u kiseloj sredini je ispitivana na sintetizovanom uzorku i rezultati su upoređeni sa komercijalnim katalizatorom u kojem su nanočestice Pt na nosaču od ugljenika razvijene površine. Pokazano je da redukcija O2, bez obzira na nosač katalizatora, sledi kinetiku prvog reda po O2 uz razmenu četiri elektrona, ali da su gustine struje veće u slučaju nosača sa volfram-karbidom. Povećana aktivnost sintetizovanog katalizatora je posledica prisustva oksofiličnih hidratisanih oksida volframa koji sprečavaju adsorpciju hidratisanog oksida na površini Pt i tako povećavaju površinu Pt dostupnu za adsorpciju i redukciju molekula kiseonika.",
publisher = "Association of Chemical Engineers of Serbia",
journal = "Hemijska industrija",
title = "Effect of tungsten carbide in carbon Pt catalyst support on electrochemical oxygen reduction in acid solution, Uticaj prisustva volfram-karbida u ugljeničnom nosaču Pt nanočestica na elektrohemijsku redukciju kiseonika u kiselom rastvoru",
pages = "311-303",
number = "2",
volume = "67",
doi = "10.2298/HEMIND120307063O"
}

Obradović, M., Babić, B. M., Krstajić, N. V.,& Gojković, S. Lj.. (2013). Effect of tungsten carbide in carbon Pt catalyst support on electrochemical oxygen reduction in acid solution. in Hemijska industrija
Association of Chemical Engineers of Serbia., 67(2), 303-311.
https://doi.org/10.2298/HEMIND120307063O

Obradović M, Babić BM, Krstajić NV, Gojković SL. Effect of tungsten carbide in carbon Pt catalyst support on electrochemical oxygen reduction in acid solution. in Hemijska industrija. 2013;67(2):303-311.
doi:10.2298/HEMIND120307063O .

Obradović, Maja, Babić, Biljana M., Krstajić, Nedeljko V., Gojković, Snežana Lj., "Effect of tungsten carbide in carbon Pt catalyst support on electrochemical oxygen reduction in acid solution" in Hemijska industrija, 67, no. 2 (2013):303-311,
https://doi.org/10.2298/HEMIND120307063O . .

TY  - JOUR
AU  - Spasojević, M.
AU  - Maricić, A.
AU  - Ribić-Zelenović, Lenka
AU  - Krstajić, Nedeljko V.
AU  - Spasojević, Pavle
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2522
AB  - Ni79.1Co18.6Cu2.3 powder was obtained by electrochemical deposition from an ammonium sulfate bath. The structure and surface morphology of the powder were detected by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemically obtained Ni79.1Co18.6Cu2.3 alloy contained an amorphous phase and nanocrystals with an average size of 6.8 nm of FCC phase of the solid solution of cobalt and copper in nickel. Nanocrystals were characterized by a high average microstrain value and high minimum density of chaotically distributed dislocations. X-ray analysis also showed that powder hydrogenation at an elevated temperature of up to 200 degrees C did not change unit cell parameters and mean crystallite size value. SEM images show the formation of two shapes of powder particles: large cauliflower-like particles and small dendritic ones. Powder pressing at 10 MPa and at 25 degrees C gave samples that were analyzed for hydrogen absorption/desorption within the temperature range of 160-200 degrees C. Changes in electrical resistivity during absorption/desorption were monitored. The reciprocal value of resistivity (electrical conductivity) was found to increase linearly with increasing amount of absorbed hydrogen. The experimental results were used to propose an absorption/desorption mechanism. The adsorbed hydrogen molecule dissociates on alloy surface, forming adsorbed atoms. Adatoms penetrate and diffuse into the bulk of the alloy, simultaneously donating their electrons to the conduction band of the alloy. The increase in the concentration of free electrons induces a decrease in electrical resistivity. The overall absorption rate during initial absorption is determined by the dissociation of adsorbed hydrogen molecules. At a later stage, the diffusion of H+ ions into the alloy bulk was found to be the rate determining step. The rate of the desorption reaction during the initial stage is governed by the recombination of adsorbed hydrogen atoms. Over time, H+ diffusion becomes the slowest step in the mechanism, hence determining the desorption rate.
PB  - Elsevier Science Sa, Lausanne
T2  - Journal of Alloys and Compounds
T1  - The kinetics of hydrogen absorption/desorption within nanostructured composite Ni79.1Co18.6Cu2.3 alloy using resistometry
EP  - 666
SP  - 660
VL  - 551
DO  - 10.1016/j.jallcom.2012.10.187
ER  - 

@article{
author = "Spasojević, M. and Maricić, A. and Ribić-Zelenović, Lenka and Krstajić, Nedeljko V. and Spasojević, Pavle",
year = "2013",
abstract = "Ni79.1Co18.6Cu2.3 powder was obtained by electrochemical deposition from an ammonium sulfate bath. The structure and surface morphology of the powder were detected by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemically obtained Ni79.1Co18.6Cu2.3 alloy contained an amorphous phase and nanocrystals with an average size of 6.8 nm of FCC phase of the solid solution of cobalt and copper in nickel. Nanocrystals were characterized by a high average microstrain value and high minimum density of chaotically distributed dislocations. X-ray analysis also showed that powder hydrogenation at an elevated temperature of up to 200 degrees C did not change unit cell parameters and mean crystallite size value. SEM images show the formation of two shapes of powder particles: large cauliflower-like particles and small dendritic ones. Powder pressing at 10 MPa and at 25 degrees C gave samples that were analyzed for hydrogen absorption/desorption within the temperature range of 160-200 degrees C. Changes in electrical resistivity during absorption/desorption were monitored. The reciprocal value of resistivity (electrical conductivity) was found to increase linearly with increasing amount of absorbed hydrogen. The experimental results were used to propose an absorption/desorption mechanism. The adsorbed hydrogen molecule dissociates on alloy surface, forming adsorbed atoms. Adatoms penetrate and diffuse into the bulk of the alloy, simultaneously donating their electrons to the conduction band of the alloy. The increase in the concentration of free electrons induces a decrease in electrical resistivity. The overall absorption rate during initial absorption is determined by the dissociation of adsorbed hydrogen molecules. At a later stage, the diffusion of H+ ions into the alloy bulk was found to be the rate determining step. The rate of the desorption reaction during the initial stage is governed by the recombination of adsorbed hydrogen atoms. Over time, H+ diffusion becomes the slowest step in the mechanism, hence determining the desorption rate.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Journal of Alloys and Compounds",
title = "The kinetics of hydrogen absorption/desorption within nanostructured composite Ni79.1Co18.6Cu2.3 alloy using resistometry",
pages = "666-660",
volume = "551",
doi = "10.1016/j.jallcom.2012.10.187"
}

Spasojević, M., Maricić, A., Ribić-Zelenović, L., Krstajić, N. V.,& Spasojević, P.. (2013). The kinetics of hydrogen absorption/desorption within nanostructured composite Ni79.1Co18.6Cu2.3 alloy using resistometry. in Journal of Alloys and Compounds
Elsevier Science Sa, Lausanne., 551, 660-666.
https://doi.org/10.1016/j.jallcom.2012.10.187

Spasojević M, Maricić A, Ribić-Zelenović L, Krstajić NV, Spasojević P. The kinetics of hydrogen absorption/desorption within nanostructured composite Ni79.1Co18.6Cu2.3 alloy using resistometry. in Journal of Alloys and Compounds. 2013;551:660-666.
doi:10.1016/j.jallcom.2012.10.187 .

Spasojević, M., Maricić, A., Ribić-Zelenović, Lenka, Krstajić, Nedeljko V., Spasojević, Pavle, "The kinetics of hydrogen absorption/desorption within nanostructured composite Ni79.1Co18.6Cu2.3 alloy using resistometry" in Journal of Alloys and Compounds, 551 (2013):660-666,
https://doi.org/10.1016/j.jallcom.2012.10.187 . .

TY  - JOUR
AU  - Elezović, Nevenka
AU  - Babić, Biljana M.
AU  - Gajić Krstajić, Ljiljana
AU  - Ercius, Peter
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko
AU  - Vračar, Ljiljana
PY  - 2012
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5733
AB  - Platinum nanocatalyst at nano-tungsten carbide was synthesized, characterized and tested for oxygen reduction reaction (ORR) in 0.1 mol dm−3 NaOH, at 25 °C. Tungsten-carbide islands on nano-tungsten particles (WC) was synthesized from gel prepared by using nanoparticles of WO3, previously produced from W-powder oxidized in H2O2. The support was porous material with high specific surface area (177 m2 g−1).The WC supported Pt (10 wt.%) catalyst was prepared by borohydride reduction method.X-ray diffraction of the catalyst demonstrates successful reduction of Pt precursor to metallic form. STEM analysis of Pt/WC catalyst showed the existence of Pt particles lower than 2 nm in size, even the clusters of Pt atoms.Electrochemically active surface area of Pt was determined from adsorption/desorption charge of hydrogen atoms.Catalytic activity of the synthesized catalyst for ORR was studied by cyclic voltammetry and linear sweep voltammetry at rotating disk electrode. The onset potential on Pt/WC for ORR, comparing with Pt/Vulcan, was shifted to the positive potentials for about 150 mV. Pt/WC catalyst shows one Tafel slope of −0.105 V dec−1, remarkable catalytic activity expressed either through the value of the current density per real surface area, or through the mass activity and excellent stability.
PB  - Elsevier
T2  - Electrochimica Acta
T1  - Pt supported on nano-tungsten carbide as a beneficial catalyst for the oxygen reduction reaction in alkaline solution
EP  - 246
SP  - 239
VL  - 69
DO  - 10.1016/j.electacta.2012.02.105
UR  - https://hdl.handle.net/21.15107/rcub_dais_465
ER  - 

@article{
author = "Elezović, Nevenka and Babić, Biljana M. and Gajić Krstajić, Ljiljana and Ercius, Peter and Radmilović, Velimir R. and Krstajić, Nedeljko and Vračar, Ljiljana",
year = "2012",
abstract = "Platinum nanocatalyst at nano-tungsten carbide was synthesized, characterized and tested for oxygen reduction reaction (ORR) in 0.1 mol dm−3 NaOH, at 25 °C. Tungsten-carbide islands on nano-tungsten particles (WC) was synthesized from gel prepared by using nanoparticles of WO3, previously produced from W-powder oxidized in H2O2. The support was porous material with high specific surface area (177 m2 g−1).The WC supported Pt (10 wt.%) catalyst was prepared by borohydride reduction method.X-ray diffraction of the catalyst demonstrates successful reduction of Pt precursor to metallic form. STEM analysis of Pt/WC catalyst showed the existence of Pt particles lower than 2 nm in size, even the clusters of Pt atoms.Electrochemically active surface area of Pt was determined from adsorption/desorption charge of hydrogen atoms.Catalytic activity of the synthesized catalyst for ORR was studied by cyclic voltammetry and linear sweep voltammetry at rotating disk electrode. The onset potential on Pt/WC for ORR, comparing with Pt/Vulcan, was shifted to the positive potentials for about 150 mV. Pt/WC catalyst shows one Tafel slope of −0.105 V dec−1, remarkable catalytic activity expressed either through the value of the current density per real surface area, or through the mass activity and excellent stability.",
publisher = "Elsevier",
journal = "Electrochimica Acta",
title = "Pt supported on nano-tungsten carbide as a beneficial catalyst for the oxygen reduction reaction in alkaline solution",
pages = "246-239",
volume = "69",
doi = "10.1016/j.electacta.2012.02.105",
url = "https://hdl.handle.net/21.15107/rcub_dais_465"
}

Elezović, N., Babić, B. M., Gajić Krstajić, L., Ercius, P., Radmilović, V. R., Krstajić, N.,& Vračar, L.. (2012). Pt supported on nano-tungsten carbide as a beneficial catalyst for the oxygen reduction reaction in alkaline solution. in Electrochimica Acta
Elsevier., 69, 239-246.
https://doi.org/10.1016/j.electacta.2012.02.105
https://hdl.handle.net/21.15107/rcub_dais_465

Elezović N, Babić BM, Gajić Krstajić L, Ercius P, Radmilović VR, Krstajić N, Vračar L. Pt supported on nano-tungsten carbide as a beneficial catalyst for the oxygen reduction reaction in alkaline solution. in Electrochimica Acta. 2012;69:239-246.
doi:10.1016/j.electacta.2012.02.105
https://hdl.handle.net/21.15107/rcub_dais_465 .

Elezović, Nevenka, Babić, Biljana M., Gajić Krstajić, Ljiljana, Ercius, Peter, Radmilović, Velimir R., Krstajić, Nedeljko, Vračar, Ljiljana, "Pt supported on nano-tungsten carbide as a beneficial catalyst for the oxygen reduction reaction in alkaline solution" in Electrochimica Acta, 69 (2012):239-246,
https://doi.org/10.1016/j.electacta.2012.02.105 .,
https://hdl.handle.net/21.15107/rcub_dais_465 .

TY  - JOUR
AU  - Obradović, Maja
AU  - Gojković, Snežana Lj.
AU  - Elezović, Nevenka R.
AU  - Ercius, P.
AU  - Radmilović, Velimir R.
AU  - Vračar, Ljiljana M.
AU  - Krstajić, Nedeljko V.
PY  - 2012
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2127
AB  - The catalytic activity of WC/Pt electrocatalysts towards hydrogen oxidation reaction (HOR) in acid solution was studied. Tungsten carbide (WC) prepared by polycondensation of resorcinol and formaldehyde in the presence of ammonium metatungstate salt and CTABr surfactant was used as the support of a Pt electrocatalyst (WC/Pt). The obtained WC/Pt electrodes were characterized by XRD, HRTEM, EDS, EELS and electrochemical measurements. HRTEM analysis showed that the WC particles possess a core-shell structure with a metallic tungsten core and a shell composed of a mixture of tungsten carbides shell (WC and W2C). The WC/Pt catalyst is composed of well-dispersed sub-nanometer Pt clusters which consist of a few to several tens of Pt atoms. EELS measurements indicate that the WC particles function as nucleation sites for Pt nanoparticles. Based on the Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations were derived to describe the HOR current-potential behavior over the entire potential region on RDE. The fitting showed that in the lower potential region HOR on Pt proceeds most likely via the Tafel-Volmer (TV) pathway. The kinetic results also showed that the WC/Pt(1%) when compared to the standard C/Pt(1%) electrode led to a remarkable enhancement of the hydrogen oxidation in an acidic medium, which was explained by H-spill-over between platinum and tungsten carbide.
PB  - Elsevier Science Sa, Lausanne
T2  - Journal of Electroanalytical Chemistry
T1  - The kinetics of the hydrogen oxidation reaction on WC/Pt catalyst with low content of Pt nano-particles
EP  - 32
SP  - 24
VL  - 671
DO  - 10.1016/j.jelechem.2012.01.026
ER  - 

@article{
author = "Obradović, Maja and Gojković, Snežana Lj. and Elezović, Nevenka R. and Ercius, P. and Radmilović, Velimir R. and Vračar, Ljiljana M. and Krstajić, Nedeljko V.",
year = "2012",
abstract = "The catalytic activity of WC/Pt electrocatalysts towards hydrogen oxidation reaction (HOR) in acid solution was studied. Tungsten carbide (WC) prepared by polycondensation of resorcinol and formaldehyde in the presence of ammonium metatungstate salt and CTABr surfactant was used as the support of a Pt electrocatalyst (WC/Pt). The obtained WC/Pt electrodes were characterized by XRD, HRTEM, EDS, EELS and electrochemical measurements. HRTEM analysis showed that the WC particles possess a core-shell structure with a metallic tungsten core and a shell composed of a mixture of tungsten carbides shell (WC and W2C). The WC/Pt catalyst is composed of well-dispersed sub-nanometer Pt clusters which consist of a few to several tens of Pt atoms. EELS measurements indicate that the WC particles function as nucleation sites for Pt nanoparticles. Based on the Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations were derived to describe the HOR current-potential behavior over the entire potential region on RDE. The fitting showed that in the lower potential region HOR on Pt proceeds most likely via the Tafel-Volmer (TV) pathway. The kinetic results also showed that the WC/Pt(1%) when compared to the standard C/Pt(1%) electrode led to a remarkable enhancement of the hydrogen oxidation in an acidic medium, which was explained by H-spill-over between platinum and tungsten carbide.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Journal of Electroanalytical Chemistry",
title = "The kinetics of the hydrogen oxidation reaction on WC/Pt catalyst with low content of Pt nano-particles",
pages = "32-24",
volume = "671",
doi = "10.1016/j.jelechem.2012.01.026"
}

Obradović, M., Gojković, S. Lj., Elezović, N. R., Ercius, P., Radmilović, V. R., Vračar, L. M.,& Krstajić, N. V.. (2012). The kinetics of the hydrogen oxidation reaction on WC/Pt catalyst with low content of Pt nano-particles. in Journal of Electroanalytical Chemistry
Elsevier Science Sa, Lausanne., 671, 24-32.
https://doi.org/10.1016/j.jelechem.2012.01.026

Obradović M, Gojković SL, Elezović NR, Ercius P, Radmilović VR, Vračar LM, Krstajić NV. The kinetics of the hydrogen oxidation reaction on WC/Pt catalyst with low content of Pt nano-particles. in Journal of Electroanalytical Chemistry. 2012;671:24-32.
doi:10.1016/j.jelechem.2012.01.026 .

Obradović, Maja, Gojković, Snežana Lj., Elezović, Nevenka R., Ercius, P., Radmilović, Velimir R., Vračar, Ljiljana M., Krstajić, Nedeljko V., "The kinetics of the hydrogen oxidation reaction on WC/Pt catalyst with low content of Pt nano-particles" in Journal of Electroanalytical Chemistry, 671 (2012):24-32,
https://doi.org/10.1016/j.jelechem.2012.01.026 . .

TY  - JOUR
AU  - Obradović, Maja
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko V.
AU  - Gojković, Snežana Lj.
PY  - 2012
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2142
AB  - Tungsten carbide was synthesized by calcination of carbon cryogel containing tungsten in a form of metatungstate. Characterization by X-ray diffraction and transmission electron microscopy indicated core-shell structure of the particles with tungsten core and tungsten carbide shell, attached to graphitized carbon. Pt nanoparticles were deposited on this material and most of them were nucleated on tungsten carbide. Cyclic voltammetry of W-C support and Pt/W-C catalyst indicated hydrogen intercalation in surface hydrous tungsten oxide. Oxidation of COads on Pt/W-C commences earlier than on Pt/C for about 100 mV. The onset potentials of MOR on Pt/W-C and Pt/C are the same, but at more positive potentials Pt/W-C catalyst is more active. It was proposed that promotion of MOR is based on bifunctional mechanism that facilitates COads removal. Stability test was performed by potential cycling of Pt/W-C and Pt/C in the supporting electrolyte and in the presence of methanol. Pt surface area loss observed in the supporting electrolyte of both catalysts after 250 cycles was about 20%. Decrease in the activity for methanol oxidation was 30% for Pt/W-C, but even 48% for Pt/C. The difference was explained by the presence of hydrous tungsten oxide on Pt in Pt/W-C catalyst, which reduces accumulation of poisoning COads.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - International Journal of Hydrogen Energy
T1  - Core-shell structured tungsten-tungsten carbide as a Pt catalyst support and its activity for methanol electrooxidation
EP  - 10679
IS  - 14
SP  - 10671
VL  - 37
DO  - 10.1016/j.ijhydene.2012.04.114
ER  - 

@article{
author = "Obradović, Maja and Babić, Biljana M. and Radmilović, Velimir R. and Krstajić, Nedeljko V. and Gojković, Snežana Lj.",
year = "2012",
abstract = "Tungsten carbide was synthesized by calcination of carbon cryogel containing tungsten in a form of metatungstate. Characterization by X-ray diffraction and transmission electron microscopy indicated core-shell structure of the particles with tungsten core and tungsten carbide shell, attached to graphitized carbon. Pt nanoparticles were deposited on this material and most of them were nucleated on tungsten carbide. Cyclic voltammetry of W-C support and Pt/W-C catalyst indicated hydrogen intercalation in surface hydrous tungsten oxide. Oxidation of COads on Pt/W-C commences earlier than on Pt/C for about 100 mV. The onset potentials of MOR on Pt/W-C and Pt/C are the same, but at more positive potentials Pt/W-C catalyst is more active. It was proposed that promotion of MOR is based on bifunctional mechanism that facilitates COads removal. Stability test was performed by potential cycling of Pt/W-C and Pt/C in the supporting electrolyte and in the presence of methanol. Pt surface area loss observed in the supporting electrolyte of both catalysts after 250 cycles was about 20%. Decrease in the activity for methanol oxidation was 30% for Pt/W-C, but even 48% for Pt/C. The difference was explained by the presence of hydrous tungsten oxide on Pt in Pt/W-C catalyst, which reduces accumulation of poisoning COads.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "International Journal of Hydrogen Energy",
title = "Core-shell structured tungsten-tungsten carbide as a Pt catalyst support and its activity for methanol electrooxidation",
pages = "10679-10671",
number = "14",
volume = "37",
doi = "10.1016/j.ijhydene.2012.04.114"
}

Obradović, M., Babić, B. M., Radmilović, V. R., Krstajić, N. V.,& Gojković, S. Lj.. (2012). Core-shell structured tungsten-tungsten carbide as a Pt catalyst support and its activity for methanol electrooxidation. in International Journal of Hydrogen Energy
Pergamon-Elsevier Science Ltd, Oxford., 37(14), 10671-10679.
https://doi.org/10.1016/j.ijhydene.2012.04.114

Obradović M, Babić BM, Radmilović VR, Krstajić NV, Gojković SL. Core-shell structured tungsten-tungsten carbide as a Pt catalyst support and its activity for methanol electrooxidation. in International Journal of Hydrogen Energy. 2012;37(14):10671-10679.
doi:10.1016/j.ijhydene.2012.04.114 .

Obradović, Maja, Babić, Biljana M., Radmilović, Velimir R., Krstajić, Nedeljko V., Gojković, Snežana Lj., "Core-shell structured tungsten-tungsten carbide as a Pt catalyst support and its activity for methanol electrooxidation" in International Journal of Hydrogen Energy, 37, no. 14 (2012):10671-10679,
https://doi.org/10.1016/j.ijhydene.2012.04.114 . .

TY  - JOUR
AU  - Jović, Borka
AU  - Lačnjevac, Uroš
AU  - Jović, Vladimir
AU  - Gajić Krstajić, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2012
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5719
AB  - MoO3 particles were co-deposited with Ni onto smooth or rough Ni supports from modified Watt’s baths of different compositions. Morphology and composition of the electrodeposits were characterized by means of cyclic voltammetry, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic activity of the composite catalysts for H2 evolution in alkaline solutions was determined by quasi-stationary polarization curves. Activity increases with MoOx content in the Ni deposit up to a limiting value. Composite Ni-MoOx catalyst performed high catalytic activity, similar to that of commercial Ni-RuO2 catalyst. Stability tests showed that Ni-MoOx codeposits are stable under condition of constant current and exhibit excellent tolerance to repeated short-circuiting.
PB  - Belgrade : Serbian Chemical Society
T2  - Journal of the Serbian Chemical Society
T1  - On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions
EP  - 224
IS  - 2
SP  - 211
VL  - 77
DO  - 10.2298/JSC110621185J
UR  - https://hdl.handle.net/21.15107/rcub_dais_258
ER  - 

@article{
author = "Jović, Borka and Lačnjevac, Uroš and Jović, Vladimir and Gajić Krstajić, Ljiljana and Krstajić, Nedeljko",
year = "2012",
abstract = "MoO3 particles were co-deposited with Ni onto smooth or rough Ni supports from modified Watt’s baths of different compositions. Morphology and composition of the electrodeposits were characterized by means of cyclic voltammetry, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic activity of the composite catalysts for H2 evolution in alkaline solutions was determined by quasi-stationary polarization curves. Activity increases with MoOx content in the Ni deposit up to a limiting value. Composite Ni-MoOx catalyst performed high catalytic activity, similar to that of commercial Ni-RuO2 catalyst. Stability tests showed that Ni-MoOx codeposits are stable under condition of constant current and exhibit excellent tolerance to repeated short-circuiting.",
publisher = "Belgrade : Serbian Chemical Society",
journal = "Journal of the Serbian Chemical Society",
title = "On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions",
pages = "224-211",
number = "2",
volume = "77",
doi = "10.2298/JSC110621185J",
url = "https://hdl.handle.net/21.15107/rcub_dais_258"
}

Jović, B., Lačnjevac, U., Jović, V., Gajić Krstajić, L.,& Krstajić, N.. (2012). On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions. in Journal of the Serbian Chemical Society
Belgrade : Serbian Chemical Society., 77(2), 211-224.
https://doi.org/10.2298/JSC110621185J
https://hdl.handle.net/21.15107/rcub_dais_258

Jović B, Lačnjevac U, Jović V, Gajić Krstajić L, Krstajić N. On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions. in Journal of the Serbian Chemical Society. 2012;77(2):211-224.
doi:10.2298/JSC110621185J
https://hdl.handle.net/21.15107/rcub_dais_258 .

Jović, Borka, Lačnjevac, Uroš, Jović, Vladimir, Gajić Krstajić, Ljiljana, Krstajić, Nedeljko, "On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions" in Journal of the Serbian Chemical Society, 77, no. 2 (2012):211-224,
https://doi.org/10.2298/JSC110621185J .,
https://hdl.handle.net/21.15107/rcub_dais_258 .

TY  - JOUR
AU  - Krstajić, Nedeljko
AU  - Gajić Krstajić, Ljiljana
AU  - Lačnjevac, Uroš
AU  - Jović, Borka
AU  - Mora, S.
AU  - Jović, Vladimir
PY  - 2011
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5646
AB  - In this work the Ni–MoOx coatings have been prepared and characterized in view of their possible application as electrocatalysts for hydrogen evolution reaction (HER) in alkaline solution. The procedure of deposition of Ni–MoOx coatings from the Watt’s type bath containing MoO3 powder particles onto Ni mesh, under the conditions of simulated industrial deposition conditions for commercial cathodes, has been presented. The morphology of the obtained coatings was investigated by SEM, the composition by EDS and the phase composition by XRD techniques. The polarization characteristics for hydrogen evolution on the obtained Ni–MoOx coatings were investigated in the 32 wt.% NaOH at 90 °C and compared with the one recorded for the commercial De Nora’s coating (DN). It was shown that the best Ni–MoOx coating exhibits almost identical polarization characteristics as the commercial one. By the cross section and XRD analysis of deposited samples it was confirmed that MoO3 powder particles were not occluded by the Ni deposit and that molybdenum species were deposited from the molybdate ions formed by dissolution of MoO3, following the mechanism of induced co-deposition. The reaction mechanism for MoO3 phase deposition has also been proposed.
PB  - Elsevier
T2  - International Journal of Hydrogen Energy
T1  - Non-noble metal composite cathodes for hydrogen evolution. Part I: The Ni–MoOx coatings electrodeposited from Watt’s type bath containing MoO3 powder particles
EP  - 6449
SP  - 6441
DO  - 10.1016/j.ijhydene.2011.02.105
UR  - https://hdl.handle.net/21.15107/rcub_dais_709
ER  - 

@article{
author = "Krstajić, Nedeljko and Gajić Krstajić, Ljiljana and Lačnjevac, Uroš and Jović, Borka and Mora, S. and Jović, Vladimir",
year = "2011",
abstract = "In this work the Ni–MoOx coatings have been prepared and characterized in view of their possible application as electrocatalysts for hydrogen evolution reaction (HER) in alkaline solution. The procedure of deposition of Ni–MoOx coatings from the Watt’s type bath containing MoO3 powder particles onto Ni mesh, under the conditions of simulated industrial deposition conditions for commercial cathodes, has been presented. The morphology of the obtained coatings was investigated by SEM, the composition by EDS and the phase composition by XRD techniques. The polarization characteristics for hydrogen evolution on the obtained Ni–MoOx coatings were investigated in the 32 wt.% NaOH at 90 °C and compared with the one recorded for the commercial De Nora’s coating (DN). It was shown that the best Ni–MoOx coating exhibits almost identical polarization characteristics as the commercial one. By the cross section and XRD analysis of deposited samples it was confirmed that MoO3 powder particles were not occluded by the Ni deposit and that molybdenum species were deposited from the molybdate ions formed by dissolution of MoO3, following the mechanism of induced co-deposition. The reaction mechanism for MoO3 phase deposition has also been proposed.",
publisher = "Elsevier",
journal = "International Journal of Hydrogen Energy",
title = "Non-noble metal composite cathodes for hydrogen evolution. Part I: The Ni–MoOx coatings electrodeposited from Watt’s type bath containing MoO3 powder particles",
pages = "6449-6441",
doi = "10.1016/j.ijhydene.2011.02.105",
url = "https://hdl.handle.net/21.15107/rcub_dais_709"
}

Krstajić, N., Gajić Krstajić, L., Lačnjevac, U., Jović, B., Mora, S.,& Jović, V.. (2011). Non-noble metal composite cathodes for hydrogen evolution. Part I: The Ni–MoOx coatings electrodeposited from Watt’s type bath containing MoO3 powder particles. in International Journal of Hydrogen Energy
Elsevier., 6441-6449.
https://doi.org/10.1016/j.ijhydene.2011.02.105
https://hdl.handle.net/21.15107/rcub_dais_709

Krstajić N, Gajić Krstajić L, Lačnjevac U, Jović B, Mora S, Jović V. Non-noble metal composite cathodes for hydrogen evolution. Part I: The Ni–MoOx coatings electrodeposited from Watt’s type bath containing MoO3 powder particles. in International Journal of Hydrogen Energy. 2011;:6441-6449.
doi:10.1016/j.ijhydene.2011.02.105
https://hdl.handle.net/21.15107/rcub_dais_709 .

Krstajić, Nedeljko, Gajić Krstajić, Ljiljana, Lačnjevac, Uroš, Jović, Borka, Mora, S., Jović, Vladimir, "Non-noble metal composite cathodes for hydrogen evolution. Part I: The Ni–MoOx coatings electrodeposited from Watt’s type bath containing MoO3 powder particles" in International Journal of Hydrogen Energy (2011):6441-6449,
https://doi.org/10.1016/j.ijhydene.2011.02.105 .,
https://hdl.handle.net/21.15107/rcub_dais_709 .

TY  - JOUR
AU  - Gojković, Snežana Lj.
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko V.
PY  - 2010
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1674
AB  - TiO2 doped by 0.5% Nb was synthesized by the acid-catalyzed sol-gel method. BET surface area was determined to be 72 m(2) g(-1). XRD measurements showed that TiO2 has structure of anatase with similar to 13 nm average crystallite size. Using Nb-TiO2 as a support, Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 were prepared by borohydride reduction method. TEM imaging of Pt-Ru/Nb-TiO2 revealed rather uniform distribution of the metallic particles on the support with a mean diameter of 3.8 nm. According to XRD analysis, Pt-Ru particles consist of the solid solution of Ru in Pt (40 at.% Ru) and a small amount of RuO2. Cyclic voltammetry of Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 indicated good conductivity of the supporting material. Oxidation of pre-adsorbed CO and methanol on Pt-Ru/Nb-TiO2 was faster than on Pt/Nb-TiO2. However, when the activities of Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 for methanol oxidation were compared to those of Pt/XC-72 and Pt-Ru/XC-72, no significant difference was observed. This means that Nb-TiO2 is a promising replacement for high area carbon supports in PEMFC anodes, but without the influence on the reaction kinetics.
PB  - Elsevier Science Sa, Lausanne
T2  - Journal of Electroanalytical Chemistry
T1  - Nb-doped TiO2 as a support of Pt and Pt-Ru anode catalyst for PEMFCs
EP  - 166
IS  - 1-2
SP  - 161
VL  - 639
DO  - 10.1016/j.jelechem.2009.12.004
ER  - 

@article{
author = "Gojković, Snežana Lj. and Babić, Biljana M. and Radmilović, Velimir R. and Krstajić, Nedeljko V.",
year = "2010",
abstract = "TiO2 doped by 0.5% Nb was synthesized by the acid-catalyzed sol-gel method. BET surface area was determined to be 72 m(2) g(-1). XRD measurements showed that TiO2 has structure of anatase with similar to 13 nm average crystallite size. Using Nb-TiO2 as a support, Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 were prepared by borohydride reduction method. TEM imaging of Pt-Ru/Nb-TiO2 revealed rather uniform distribution of the metallic particles on the support with a mean diameter of 3.8 nm. According to XRD analysis, Pt-Ru particles consist of the solid solution of Ru in Pt (40 at.% Ru) and a small amount of RuO2. Cyclic voltammetry of Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 indicated good conductivity of the supporting material. Oxidation of pre-adsorbed CO and methanol on Pt-Ru/Nb-TiO2 was faster than on Pt/Nb-TiO2. However, when the activities of Pt/Nb-TiO2 and Pt-Ru/Nb-TiO2 for methanol oxidation were compared to those of Pt/XC-72 and Pt-Ru/XC-72, no significant difference was observed. This means that Nb-TiO2 is a promising replacement for high area carbon supports in PEMFC anodes, but without the influence on the reaction kinetics.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Journal of Electroanalytical Chemistry",
title = "Nb-doped TiO2 as a support of Pt and Pt-Ru anode catalyst for PEMFCs",
pages = "166-161",
number = "1-2",
volume = "639",
doi = "10.1016/j.jelechem.2009.12.004"
}

Gojković, S. Lj., Babić, B. M., Radmilović, V. R.,& Krstajić, N. V.. (2010). Nb-doped TiO2 as a support of Pt and Pt-Ru anode catalyst for PEMFCs. in Journal of Electroanalytical Chemistry
Elsevier Science Sa, Lausanne., 639(1-2), 161-166.
https://doi.org/10.1016/j.jelechem.2009.12.004

Gojković SL, Babić BM, Radmilović VR, Krstajić NV. Nb-doped TiO2 as a support of Pt and Pt-Ru anode catalyst for PEMFCs. in Journal of Electroanalytical Chemistry. 2010;639(1-2):161-166.
doi:10.1016/j.jelechem.2009.12.004 .

Gojković, Snežana Lj., Babić, Biljana M., Radmilović, Velimir R., Krstajić, Nedeljko V., "Nb-doped TiO2 as a support of Pt and Pt-Ru anode catalyst for PEMFCs" in Journal of Electroanalytical Chemistry, 639, no. 1-2 (2010):161-166,
https://doi.org/10.1016/j.jelechem.2009.12.004 . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Gajić Krstajić, Ljiljana
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko
AU  - Vračar, Ljiljana
PY  - 2010
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5617
AB  - In order to point out the effect of the support to the catalyst for oxygen reduction reaction nano-crystalline Nb-doped TiO2 was synthesized through a modified sol-gel route procedure. The specific surface area of the support, SBET, and pore size distribution, were calculated from the adsorption isotherms using the gravimetric McBain method. The support was characterized by X-ray diffraction (XRD) technique. The borohydride reduction method was used to prepare Nb-TiO2 supported Pt (20 wt.%) catalyst. The synthesized catalyst was analyzed by TEM technique. Finally, the catalytic activity of this new catalyst for oxygen reduction reaction was investigated in acid solution, in the absence and the presence of methanol, and its activity was compared towards the results on C/Pt catalysts. Kinetic analysis reveals that the oxygen reduction reaction on Nb-TiO2/Pt catalyst follows four-electron process leading to water, as in the case of C/Pt electrode, but the Tafel plots normalized to the electrochemically active surface area show very remarkable enhancement in activity of Nb-TiO2/Pt expressed through the value of the current density at the constant potential. Moreover, Nb-TiO2/Pt catalyst exhibits higher methanol tolerance during the oxygen reduction reaction than the C/Pt catalyst. The enhancement in the activity of Nb-TiO2/Pt is consequence of both: the interactions of Pt nanoparticles with the support and the energy shift of the surface d-states with respect to the Fermi level what changes the surface reactivity. © 2010 Elsevier B.V.
PB  - Elsevier
T2  - Journal of Power Sources
T1  - Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction
EP  - 3968
IS  - 13
SP  - 3961
VL  - 195
DO  - 10.1016/j.jpowsour.2010.01.035
UR  - https://hdl.handle.net/21.15107/rcub_dais_3418
ER  - 

@article{
author = "Elezović, Nevenka R. and Babić, Biljana M. and Gajić Krstajić, Ljiljana and Radmilović, Velimir R. and Krstajić, Nedeljko and Vračar, Ljiljana",
year = "2010",
abstract = "In order to point out the effect of the support to the catalyst for oxygen reduction reaction nano-crystalline Nb-doped TiO2 was synthesized through a modified sol-gel route procedure. The specific surface area of the support, SBET, and pore size distribution, were calculated from the adsorption isotherms using the gravimetric McBain method. The support was characterized by X-ray diffraction (XRD) technique. The borohydride reduction method was used to prepare Nb-TiO2 supported Pt (20 wt.%) catalyst. The synthesized catalyst was analyzed by TEM technique. Finally, the catalytic activity of this new catalyst for oxygen reduction reaction was investigated in acid solution, in the absence and the presence of methanol, and its activity was compared towards the results on C/Pt catalysts. Kinetic analysis reveals that the oxygen reduction reaction on Nb-TiO2/Pt catalyst follows four-electron process leading to water, as in the case of C/Pt electrode, but the Tafel plots normalized to the electrochemically active surface area show very remarkable enhancement in activity of Nb-TiO2/Pt expressed through the value of the current density at the constant potential. Moreover, Nb-TiO2/Pt catalyst exhibits higher methanol tolerance during the oxygen reduction reaction than the C/Pt catalyst. The enhancement in the activity of Nb-TiO2/Pt is consequence of both: the interactions of Pt nanoparticles with the support and the energy shift of the surface d-states with respect to the Fermi level what changes the surface reactivity. © 2010 Elsevier B.V.",
publisher = "Elsevier",
journal = "Journal of Power Sources",
title = "Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction",
pages = "3968-3961",
number = "13",
volume = "195",
doi = "10.1016/j.jpowsour.2010.01.035",
url = "https://hdl.handle.net/21.15107/rcub_dais_3418"
}

Elezović, N. R., Babić, B. M., Gajić Krstajić, L., Radmilović, V. R., Krstajić, N.,& Vračar, L.. (2010). Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction. in Journal of Power Sources
Elsevier., 195(13), 3961-3968.
https://doi.org/10.1016/j.jpowsour.2010.01.035
https://hdl.handle.net/21.15107/rcub_dais_3418

Elezović NR, Babić BM, Gajić Krstajić L, Radmilović VR, Krstajić N, Vračar L. Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction. in Journal of Power Sources. 2010;195(13):3961-3968.
doi:10.1016/j.jpowsour.2010.01.035
https://hdl.handle.net/21.15107/rcub_dais_3418 .

Elezović, Nevenka R., Babić, Biljana M., Gajić Krstajić, Ljiljana, Radmilović, Velimir R., Krstajić, Nedeljko, Vračar, Ljiljana, "Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction" in Journal of Power Sources, 195, no. 13 (2010):3961-3968,
https://doi.org/10.1016/j.jpowsour.2010.01.035 .,
https://hdl.handle.net/21.15107/rcub_dais_3418 .

TY  - JOUR
AU  - Elezović, Nevenka
AU  - Gajić Krstajić, Ljiljana
AU  - Vračar, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2010
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5591
AB  - The influence of poisoning of MoOx-Pt catalyst by CO on the kinetics of H2 oxidation reaction (HOR) at MoOx-Pt electrode in 0.5 mol dm-3 HClO4 saturated with H 2 containing 100 ppm CO, was examined on rotating disc electrode (RDE) at 25 °C. MoOx-Pt nano-catalyst prepared by the polyole method combined with MoOx post-deposition was supported on commercial carbon black, Vulcan XC-72. The MoOx-Pt/C catalyst was characterized by TEM technique. The catalyst composition is very similar to the nominal one and post-deposited MoOx species block only a small fraction of the active Pt particle surface area. MoOx deposition on the carbon support can be ruled out from the EDAX results and from the low mobility of these oxides under used conditions. Based on Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations from a dual-pathway model were derived to describe oxidation current-potential behavior on RDE over entire potential range, at various CO coverages. The polarization RDE curves were fitted with derived polarization equations according to the proposed model. The fitting showed that the HOR proceeded most likely via the Tafel-Volmer (TV) pathway. A very high electrocatalytic activity observed at MoOx-Pt catalyst for the hydrogen oxidation reaction in the presence of 100 ppm CO is achieved through chemical surface reaction of adsorbed CO with Mo surface oxides. © 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.
PB  - Elsevier
T2  - International Journal of Hydrogen Energy
T2  - International Journal of Hydrogen Energy
T1  - Effect of chemisorbed CO on MoOx-Pt/C electrode on the kinetics of hydrogen oxidation reaction
EP  - 12887
IS  - 23
SP  - 12878
VL  - 35
DO  - 10.1016/j.ijhydene.2010.09.004
UR  - https://hdl.handle.net/21.15107/rcub_dais_3410
ER  - 

@article{
author = "Elezović, Nevenka and Gajić Krstajić, Ljiljana and Vračar, Ljiljana and Krstajić, Nedeljko",
year = "2010",
abstract = "The influence of poisoning of MoOx-Pt catalyst by CO on the kinetics of H2 oxidation reaction (HOR) at MoOx-Pt electrode in 0.5 mol dm-3 HClO4 saturated with H 2 containing 100 ppm CO, was examined on rotating disc electrode (RDE) at 25 °C. MoOx-Pt nano-catalyst prepared by the polyole method combined with MoOx post-deposition was supported on commercial carbon black, Vulcan XC-72. The MoOx-Pt/C catalyst was characterized by TEM technique. The catalyst composition is very similar to the nominal one and post-deposited MoOx species block only a small fraction of the active Pt particle surface area. MoOx deposition on the carbon support can be ruled out from the EDAX results and from the low mobility of these oxides under used conditions. Based on Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations from a dual-pathway model were derived to describe oxidation current-potential behavior on RDE over entire potential range, at various CO coverages. The polarization RDE curves were fitted with derived polarization equations according to the proposed model. The fitting showed that the HOR proceeded most likely via the Tafel-Volmer (TV) pathway. A very high electrocatalytic activity observed at MoOx-Pt catalyst for the hydrogen oxidation reaction in the presence of 100 ppm CO is achieved through chemical surface reaction of adsorbed CO with Mo surface oxides. © 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.",
publisher = "Elsevier",
journal = "International Journal of Hydrogen Energy, International Journal of Hydrogen Energy",
title = "Effect of chemisorbed CO on MoOx-Pt/C electrode on the kinetics of hydrogen oxidation reaction",
pages = "12887-12878",
number = "23",
volume = "35",
doi = "10.1016/j.ijhydene.2010.09.004",
url = "https://hdl.handle.net/21.15107/rcub_dais_3410"
}

Elezović, N., Gajić Krstajić, L., Vračar, L.,& Krstajić, N.. (2010). Effect of chemisorbed CO on MoOx-Pt/C electrode on the kinetics of hydrogen oxidation reaction. in International Journal of Hydrogen Energy
Elsevier., 35(23), 12878-12887.
https://doi.org/10.1016/j.ijhydene.2010.09.004
https://hdl.handle.net/21.15107/rcub_dais_3410

Elezović N, Gajić Krstajić L, Vračar L, Krstajić N. Effect of chemisorbed CO on MoOx-Pt/C electrode on the kinetics of hydrogen oxidation reaction. in International Journal of Hydrogen Energy. 2010;35(23):12878-12887.
doi:10.1016/j.ijhydene.2010.09.004
https://hdl.handle.net/21.15107/rcub_dais_3410 .

Elezović, Nevenka, Gajić Krstajić, Ljiljana, Vračar, Ljiljana, Krstajić, Nedeljko, "Effect of chemisorbed CO on MoOx-Pt/C electrode on the kinetics of hydrogen oxidation reaction" in International Journal of Hydrogen Energy, 35, no. 23 (2010):12878-12887,
https://doi.org/10.1016/j.ijhydene.2010.09.004 .,
https://hdl.handle.net/21.15107/rcub_dais_3410 .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R
AU  - Vračar, Ljiljana M
AU  - Krstajić, Nedeljko V
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5540
AB  - The oxygen reduction reaction (ORR) was studied at carbon supported MoOx-Pt/C and TiOx-Pt nanocatalysts in 0.5 mol dm(-3) HClO4 solution, at 25 degrees C. The MoOx-Pt/C and TiOx-Pt/C catalysts were prepared by the polyole method combined by MoOx or TiOx post-deposition. Home made catalysts were characterized by TEM and EDX techniques. It was found that catalyst nanoparticles were homogenously distributed over the carbon support with a mean particle size about 2.5 nm. Quite similar distribution and particle size was previously obtained for Pt/C catalyst. Results confirmed that MoOx and TiOx post-deposition did not lead to a significant growth of the Pt nanoparticles. The ORR kinetics was investigated by cyclic voltammetry and linear sweep voltammetry at the rotating disc electrode. These results showed the existence of two E - logj regions, usually observed with polycrystalline Pt in acid solution. It was proposed that the main path in the ORR mechanism on MoOx-Pt/C and TiOx-Pt/C catalysts was the direct four-electron process with the transfer of the first electron as the rate-determining step. The increase in catalytic activity for ORR on MoOx-Pt/C and TiOx-Pt/C catalysts, in comparison with Pt/C catalyst, was explained by synergetic effects due to the formation of the interface between the platinum and oxide materials and by spillover due to the surface diffusion of oxygen reaction intermediates.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Electrochimica Acta
T1  - Synthesis and characterization of MoOx-Pt/C and TiOx-Pt/C nano-catalysts for oxygen reduction
EP  - 2409
IS  - 9
SP  - 2404
VL  - 54
DO  - 10.1016/j.electacta.2008.03.015
ER  - 

@article{
author = "Elezović, Nevenka R. and Babić, Biljana M. and Radmilović, Velimir R and Vračar, Ljiljana M and Krstajić, Nedeljko V",
year = "2009",
abstract = "The oxygen reduction reaction (ORR) was studied at carbon supported MoOx-Pt/C and TiOx-Pt nanocatalysts in 0.5 mol dm(-3) HClO4 solution, at 25 degrees C. The MoOx-Pt/C and TiOx-Pt/C catalysts were prepared by the polyole method combined by MoOx or TiOx post-deposition. Home made catalysts were characterized by TEM and EDX techniques. It was found that catalyst nanoparticles were homogenously distributed over the carbon support with a mean particle size about 2.5 nm. Quite similar distribution and particle size was previously obtained for Pt/C catalyst. Results confirmed that MoOx and TiOx post-deposition did not lead to a significant growth of the Pt nanoparticles. The ORR kinetics was investigated by cyclic voltammetry and linear sweep voltammetry at the rotating disc electrode. These results showed the existence of two E - logj regions, usually observed with polycrystalline Pt in acid solution. It was proposed that the main path in the ORR mechanism on MoOx-Pt/C and TiOx-Pt/C catalysts was the direct four-electron process with the transfer of the first electron as the rate-determining step. The increase in catalytic activity for ORR on MoOx-Pt/C and TiOx-Pt/C catalysts, in comparison with Pt/C catalyst, was explained by synergetic effects due to the formation of the interface between the platinum and oxide materials and by spillover due to the surface diffusion of oxygen reaction intermediates.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Electrochimica Acta",
title = "Synthesis and characterization of MoOx-Pt/C and TiOx-Pt/C nano-catalysts for oxygen reduction",
pages = "2409-2404",
number = "9",
volume = "54",
doi = "10.1016/j.electacta.2008.03.015"
}

Elezović, N. R., Babić, B. M., Radmilović, V. R., Vračar, L. M.,& Krstajić, N. V.. (2009). Synthesis and characterization of MoOx-Pt/C and TiOx-Pt/C nano-catalysts for oxygen reduction. in Electrochimica Acta
Pergamon-Elsevier Science Ltd, Oxford., 54(9), 2404-2409.
https://doi.org/10.1016/j.electacta.2008.03.015

Elezović NR, Babić BM, Radmilović VR, Vračar LM, Krstajić NV. Synthesis and characterization of MoOx-Pt/C and TiOx-Pt/C nano-catalysts for oxygen reduction. in Electrochimica Acta. 2009;54(9):2404-2409.
doi:10.1016/j.electacta.2008.03.015 .

Elezović, Nevenka R., Babić, Biljana M., Radmilović, Velimir R, Vračar, Ljiljana M, Krstajić, Nedeljko V, "Synthesis and characterization of MoOx-Pt/C and TiOx-Pt/C nano-catalysts for oxygen reduction" in Electrochimica Acta, 54, no. 9 (2009):2404-2409,
https://doi.org/10.1016/j.electacta.2008.03.015 . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Vračar, Ljiljana M
AU  - Radmilović, Velimir R
AU  - Krstajić, Nedeljko V
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5537
AB  - The hydrogen oxidation reaction (HOR) was studied at the home made TiOx-Pt/C nanocatalysts in 0.5 mol dm(-3) HClO4 at 25 degrees C. Pt/C catalyst was first synthesized by modified ethylene glycol method (EG) on commercially used carbon support (Vulcan XC-72). Then TiOx-Pt/C catalyst was prepared by the polyole method followed by TiOx post-deposition. The synthesized catalyst was characterized by XRD, TEM and EDX techniques. It was found that Pt/C catalyst nanoparticles were homogenously distributed over carbon support with the mean particle size of about 2.4 nm. The quite similar, homogenous distribution and particle size were obtained for Pt/C doped by TiOx catalyst which was the confirmation that TiOx post-deposition did not lead to significant growth of the Pt nanoparticles. The electrochemically active surface area of the catalyst was determined by using the cyclic voltammetry technique. The kinetics of hydrogen oxidation was investigated by the linear sweep voltammetry technique at the rotating disc electrode (RDE). The kinetic equations used for the analysis were derived considering the reversible or irreversible nature of the kinetics of the HOR. It was found that the hydrogen oxidation reaction for an investigated catalyst proceeded as an electrochemically reversible reaction. The values determined for the kinetic parameters-Tafel slope of 28 mV dec(-1) and exchange current density about 0.4 mA cm(Pt)(-2) are in good agreement with usually reported values for a hydrogen oxidation reaction with platinum catalysts in acid solutions.
PB  - Royal Soc Chemistry, Cambridge
T2  - Physical Chemistry Chemical Physics
T1  - Preparation and characterization TiOx-Pt/C catalyst for hydrogen oxidation reaction
EP  - 5197
IS  - 25
SP  - 5192
VL  - 11
DO  - 10.1039/b822249e
ER  - 

@article{
author = "Elezović, Nevenka R. and Babić, Biljana M. and Vračar, Ljiljana M and Radmilović, Velimir R and Krstajić, Nedeljko V",
year = "2009",
abstract = "The hydrogen oxidation reaction (HOR) was studied at the home made TiOx-Pt/C nanocatalysts in 0.5 mol dm(-3) HClO4 at 25 degrees C. Pt/C catalyst was first synthesized by modified ethylene glycol method (EG) on commercially used carbon support (Vulcan XC-72). Then TiOx-Pt/C catalyst was prepared by the polyole method followed by TiOx post-deposition. The synthesized catalyst was characterized by XRD, TEM and EDX techniques. It was found that Pt/C catalyst nanoparticles were homogenously distributed over carbon support with the mean particle size of about 2.4 nm. The quite similar, homogenous distribution and particle size were obtained for Pt/C doped by TiOx catalyst which was the confirmation that TiOx post-deposition did not lead to significant growth of the Pt nanoparticles. The electrochemically active surface area of the catalyst was determined by using the cyclic voltammetry technique. The kinetics of hydrogen oxidation was investigated by the linear sweep voltammetry technique at the rotating disc electrode (RDE). The kinetic equations used for the analysis were derived considering the reversible or irreversible nature of the kinetics of the HOR. It was found that the hydrogen oxidation reaction for an investigated catalyst proceeded as an electrochemically reversible reaction. The values determined for the kinetic parameters-Tafel slope of 28 mV dec(-1) and exchange current density about 0.4 mA cm(Pt)(-2) are in good agreement with usually reported values for a hydrogen oxidation reaction with platinum catalysts in acid solutions.",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "Physical Chemistry Chemical Physics",
title = "Preparation and characterization TiOx-Pt/C catalyst for hydrogen oxidation reaction",
pages = "5197-5192",
number = "25",
volume = "11",
doi = "10.1039/b822249e"
}

Elezović, N. R., Babić, B. M., Vračar, L. M., Radmilović, V. R.,& Krstajić, N. V.. (2009). Preparation and characterization TiOx-Pt/C catalyst for hydrogen oxidation reaction. in Physical Chemistry Chemical Physics
Royal Soc Chemistry, Cambridge., 11(25), 5192-5197.
https://doi.org/10.1039/b822249e

Elezović NR, Babić BM, Vračar LM, Radmilović VR, Krstajić NV. Preparation and characterization TiOx-Pt/C catalyst for hydrogen oxidation reaction. in Physical Chemistry Chemical Physics. 2009;11(25):5192-5197.
doi:10.1039/b822249e .

Elezović, Nevenka R., Babić, Biljana M., Vračar, Ljiljana M, Radmilović, Velimir R, Krstajić, Nedeljko V, "Preparation and characterization TiOx-Pt/C catalyst for hydrogen oxidation reaction" in Physical Chemistry Chemical Physics, 11, no. 25 (2009):5192-5197,
https://doi.org/10.1039/b822249e . .

TY  - JOUR
AU  - Babić, Biljana M.
AU  - Gulicovski, Jelena
AU  - Gajić Krstajić, Ljiljana
AU  - Elezović, Nevenka
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko
AU  - Vračar, Ljiljana
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5531
AB  - The kinetics and mechanism of the hydrogen oxidation reaction were studied in 0.5 mol dm-3 HClO4 solution on an electrode based on titanium oxide with Magneli phase structure-supported platinum electrocatalyst applied on rotation Au disk electrode. Pt catalyst was prepared by impregnation method from 2-propanol solution of Pt(NH3)2(NO2)2 and sub-stoichiometric titanium oxide powder. Sub-stiochiometric titanium oxide support was characterized by X-ray diffraction and BET techniques. The synthesized catalyst was analyzed by TEM technique. Based on Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations were derived to describe the hydrogen oxidation current-potential behavior on RDE over the entire potential region. The polarization RDE curves were fitted with derived polarization equations according to proposed model. The fitting shows that the HOR on Pt proceeds most likely via the Tafel-Volmer (TV) pathway in the lower potential region, while the Heyrovsky-Volmer (HV) pathway is operative in the higher potential region. It is pointed out that Tafel equation that has been frequently used for the kinetics analysis in the HOR, can not reproduce the polarization curves measured with high mass-transport rates. Polarization measurements on RDE revealed that the Pt catalyst deposited on titanium suboxide support showed equal specific activity for the HOR compared to conventional carbon-supported Pt fuel cell catalyst. © 2008 Elsevier B.V. All rights reserved.
PB  - Elsevier
T2  - Journal of Power Sources
T1  - Kinetic study of the hydrogen oxidation reaction on sub-stoichiometric titanium oxide-supported platinum electrocatalyst in acid solution
EP  - 106
IS  - 1
SP  - 99
VL  - 193
DO  - 10.1016/j.jpowsour.2008.11.142
UR  - https://hdl.handle.net/21.15107/rcub_dais_3480
ER  - 

@article{
author = "Babić, Biljana M. and Gulicovski, Jelena and Gajić Krstajić, Ljiljana and Elezović, Nevenka and Radmilović, Velimir R. and Krstajić, Nedeljko and Vračar, Ljiljana",
year = "2009",
abstract = "The kinetics and mechanism of the hydrogen oxidation reaction were studied in 0.5 mol dm-3 HClO4 solution on an electrode based on titanium oxide with Magneli phase structure-supported platinum electrocatalyst applied on rotation Au disk electrode. Pt catalyst was prepared by impregnation method from 2-propanol solution of Pt(NH3)2(NO2)2 and sub-stoichiometric titanium oxide powder. Sub-stiochiometric titanium oxide support was characterized by X-ray diffraction and BET techniques. The synthesized catalyst was analyzed by TEM technique. Based on Tafel-Heyrovsky-Volmer mechanism the corresponding kinetic equations were derived to describe the hydrogen oxidation current-potential behavior on RDE over the entire potential region. The polarization RDE curves were fitted with derived polarization equations according to proposed model. The fitting shows that the HOR on Pt proceeds most likely via the Tafel-Volmer (TV) pathway in the lower potential region, while the Heyrovsky-Volmer (HV) pathway is operative in the higher potential region. It is pointed out that Tafel equation that has been frequently used for the kinetics analysis in the HOR, can not reproduce the polarization curves measured with high mass-transport rates. Polarization measurements on RDE revealed that the Pt catalyst deposited on titanium suboxide support showed equal specific activity for the HOR compared to conventional carbon-supported Pt fuel cell catalyst. © 2008 Elsevier B.V. All rights reserved.",
publisher = "Elsevier",
journal = "Journal of Power Sources",
title = "Kinetic study of the hydrogen oxidation reaction on sub-stoichiometric titanium oxide-supported platinum electrocatalyst in acid solution",
pages = "106-99",
number = "1",
volume = "193",
doi = "10.1016/j.jpowsour.2008.11.142",
url = "https://hdl.handle.net/21.15107/rcub_dais_3480"
}

Babić, B. M., Gulicovski, J., Gajić Krstajić, L., Elezović, N., Radmilović, V. R., Krstajić, N.,& Vračar, L.. (2009). Kinetic study of the hydrogen oxidation reaction on sub-stoichiometric titanium oxide-supported platinum electrocatalyst in acid solution. in Journal of Power Sources
Elsevier., 193(1), 99-106.
https://doi.org/10.1016/j.jpowsour.2008.11.142
https://hdl.handle.net/21.15107/rcub_dais_3480

Babić BM, Gulicovski J, Gajić Krstajić L, Elezović N, Radmilović VR, Krstajić N, Vračar L. Kinetic study of the hydrogen oxidation reaction on sub-stoichiometric titanium oxide-supported platinum electrocatalyst in acid solution. in Journal of Power Sources. 2009;193(1):99-106.
doi:10.1016/j.jpowsour.2008.11.142
https://hdl.handle.net/21.15107/rcub_dais_3480 .

Babić, Biljana M., Gulicovski, Jelena, Gajić Krstajić, Ljiljana, Elezović, Nevenka, Radmilović, Velimir R., Krstajić, Nedeljko, Vračar, Ljiljana, "Kinetic study of the hydrogen oxidation reaction on sub-stoichiometric titanium oxide-supported platinum electrocatalyst in acid solution" in Journal of Power Sources, 193, no. 1 (2009):99-106,
https://doi.org/10.1016/j.jpowsour.2008.11.142 .,
https://hdl.handle.net/21.15107/rcub_dais_3480 .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Gajić Krstajić, Ljiljana
AU  - Radmilović, Velimir R.
AU  - Vračar, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5525
AB  - The influence of poisoning of Pt catalyst by CO on the kinetics and mechanism of H2 oxidation reaction (HOR) at Pt/C electrode in 0.5 mol dm-3 HClO4, saturated with H2 containing 100 ppm CO, was examined with rotating disc electrode (RDE) at 22 °C. Commercial carbon black, Vulcan XC-72 was used as support, while Pt/C catalyst was prepared by modified polyol synthesis method in an ethylene glycol (EG) solution. The kinetically controlled current (Ik) for the HOR at Pt/C decreases significantly at CO coverage (ΘCO) > 0.6. For ΘCO < 0.6 the HOR takes place through Tafel-Volmer mechanism with Tafel reaction as rate-determining step at the low CO coverage, while Volmer step controls the overall reaction rate at the medium CO coverage. When CO coverage is higher then 0.6, Heyrovsky-Volmer mechanism is operative for the HOR with Heyrovsky as the rate-determining step (rds). © 2008 Elsevier Ltd. All rights reserved.
PB  - Elsevier
T2  - Electrochimica Acta
T1  - Effect of chemisorbed carbon monoxide on Pt/C electrode on the mechanism of the hydrogen oxidation reaction
EP  - 1382
IS  - 4
SP  - 1375
VL  - 54
DO  - 10.1016/j.electacta.2008.08.067
UR  - https://hdl.handle.net/21.15107/rcub_dais_3485
ER  - 

@article{
author = "Elezović, Nevenka R. and Gajić Krstajić, Ljiljana and Radmilović, Velimir R. and Vračar, Ljiljana and Krstajić, Nedeljko",
year = "2009",
abstract = "The influence of poisoning of Pt catalyst by CO on the kinetics and mechanism of H2 oxidation reaction (HOR) at Pt/C electrode in 0.5 mol dm-3 HClO4, saturated with H2 containing 100 ppm CO, was examined with rotating disc electrode (RDE) at 22 °C. Commercial carbon black, Vulcan XC-72 was used as support, while Pt/C catalyst was prepared by modified polyol synthesis method in an ethylene glycol (EG) solution. The kinetically controlled current (Ik) for the HOR at Pt/C decreases significantly at CO coverage (ΘCO) > 0.6. For ΘCO < 0.6 the HOR takes place through Tafel-Volmer mechanism with Tafel reaction as rate-determining step at the low CO coverage, while Volmer step controls the overall reaction rate at the medium CO coverage. When CO coverage is higher then 0.6, Heyrovsky-Volmer mechanism is operative for the HOR with Heyrovsky as the rate-determining step (rds). © 2008 Elsevier Ltd. All rights reserved.",
publisher = "Elsevier",
journal = "Electrochimica Acta",
title = "Effect of chemisorbed carbon monoxide on Pt/C electrode on the mechanism of the hydrogen oxidation reaction",
pages = "1382-1375",
number = "4",
volume = "54",
doi = "10.1016/j.electacta.2008.08.067",
url = "https://hdl.handle.net/21.15107/rcub_dais_3485"
}

Elezović, N. R., Gajić Krstajić, L., Radmilović, V. R., Vračar, L.,& Krstajić, N.. (2009). Effect of chemisorbed carbon monoxide on Pt/C electrode on the mechanism of the hydrogen oxidation reaction. in Electrochimica Acta
Elsevier., 54(4), 1375-1382.
https://doi.org/10.1016/j.electacta.2008.08.067
https://hdl.handle.net/21.15107/rcub_dais_3485

Elezović NR, Gajić Krstajić L, Radmilović VR, Vračar L, Krstajić N. Effect of chemisorbed carbon monoxide on Pt/C electrode on the mechanism of the hydrogen oxidation reaction. in Electrochimica Acta. 2009;54(4):1375-1382.
doi:10.1016/j.electacta.2008.08.067
https://hdl.handle.net/21.15107/rcub_dais_3485 .

Elezović, Nevenka R., Gajić Krstajić, Ljiljana, Radmilović, Velimir R., Vračar, Ljiljana, Krstajić, Nedeljko, "Effect of chemisorbed carbon monoxide on Pt/C electrode on the mechanism of the hydrogen oxidation reaction" in Electrochimica Acta, 54, no. 4 (2009):1375-1382,
https://doi.org/10.1016/j.electacta.2008.08.067 .,
https://hdl.handle.net/21.15107/rcub_dais_3485 .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Krstajić, Nedeljko V.
AU  - Vračar, Ljiljana M.
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1282
AB  - The oxidation of methanol and reduction of oxygen were studied on MoOx-Pt/C nano-catalysts prepared by the polyole method combined by MoOx post-deposition. The catalysts were characterized by TEM and EDX. The presented composition of the electrode is very similar to the nominal ones and post-deposited MoOx species block only a small fraction of the active Pt particle surface area. MoOx deposition on the carbon support can be ruled out from the EDX results and the low mobility of these oxides at corresponding conditions. The electrode catalytic activity in the electrooxidation of methanol and the reduction of oxygen was studied by steady-state voltammetry and cyclic voltammetry. MoOx-Pt/C catalyst exhibits higher catalytic activity than Pt/C for the oxygen reduction. The catalytic effect in oxidation of methanol is achieved only under potentiodynamic conditions, when poisoning species have no enough time to develop fully.
PB  - Elsevier Science Bv, Amsterdam
T2  - Journal of Power Sources
T1  - Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation
EP  - 255
IS  - 1
SP  - 250
VL  - 175
DO  - 10.1016/j.jpowsour.2007.09.011
ER  - 

@article{
author = "Elezović, Nevenka R. and Babić, Biljana M. and Radmilović, Velimir R. and Gojković, Snežana Lj. and Krstajić, Nedeljko V. and Vračar, Ljiljana M.",
year = "2008",
abstract = "The oxidation of methanol and reduction of oxygen were studied on MoOx-Pt/C nano-catalysts prepared by the polyole method combined by MoOx post-deposition. The catalysts were characterized by TEM and EDX. The presented composition of the electrode is very similar to the nominal ones and post-deposited MoOx species block only a small fraction of the active Pt particle surface area. MoOx deposition on the carbon support can be ruled out from the EDX results and the low mobility of these oxides at corresponding conditions. The electrode catalytic activity in the electrooxidation of methanol and the reduction of oxygen was studied by steady-state voltammetry and cyclic voltammetry. MoOx-Pt/C catalyst exhibits higher catalytic activity than Pt/C for the oxygen reduction. The catalytic effect in oxidation of methanol is achieved only under potentiodynamic conditions, when poisoning species have no enough time to develop fully.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Journal of Power Sources",
title = "Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation",
pages = "255-250",
number = "1",
volume = "175",
doi = "10.1016/j.jpowsour.2007.09.011"
}

Elezović, N. R., Babić, B. M., Radmilović, V. R., Gojković, S. Lj., Krstajić, N. V.,& Vračar, L. M.. (2008). Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation. in Journal of Power Sources
Elsevier Science Bv, Amsterdam., 175(1), 250-255.
https://doi.org/10.1016/j.jpowsour.2007.09.011

Elezović NR, Babić BM, Radmilović VR, Gojković SL, Krstajić NV, Vračar LM. Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation. in Journal of Power Sources. 2008;175(1):250-255.
doi:10.1016/j.jpowsour.2007.09.011 .

Elezović, Nevenka R., Babić, Biljana M., Radmilović, Velimir R., Gojković, Snežana Lj., Krstajić, Nedeljko V., Vračar, Ljiljana M., "Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation" in Journal of Power Sources, 175, no. 1 (2008):250-255,
https://doi.org/10.1016/j.jpowsour.2007.09.011 . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Krstajić, Nedeljko V.
AU  - Gojković, Snežana Lj.
AU  - Vračar, Ljiljana M.
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1346
AB  - The temperature dependence of oxygen reduction reaction (ORR) was studied on highly dispersed Pt nanoparticles supported on a carbon cryo-gel. The specific surface area of the support was 517 m2 g-1, the Pt particles diameter was about 2.7 nm and the loading of the catalyst was 20 wt.%. The kinetics of the ORR at the Pt/C electrode was examined in 0.50 mol dm-3 HClO4 solution in the temperature range from 274 to 318 K. At all temperatures, two distinct E-log j regions were observed; at low current densities with a slope of -2.3RT/F and at high current densities with a slope of -2.3´2RT/F. In order to confirm the mechanism of oxygen reduction previously suggested at a polycrystalline Pt and a Pt/Ebonex nanostructured electrode, the apparent enthalpies of activation at selected potentials vs. the reversible hydrogen electrode were calculated in both current density regions. Although ∆H ≠a,1  gt  ∆H ≠a,h , it was a,1 a, h found that the enthalpies of activation at the zero Galvani potential difference were the same and hence it could be concluded that the rate-determining step of the ORR was the same in both current density regions. The synthesized Pt/C catalyst showed a small enhancement in the catalytic activity for ORR in comparison to the polycrystalline Pt, but no change in the mechanism of the reaction.
AB  - Kinetika reakcije redukcije kiseonika je ispitivana na nanočesticama platine dispergovanim na ugljeničnom nosaču, u 0,50 mol dm-3 HClO4, u temperaturnom intervalu od 278 do 318 K. Za sintezu Pt katalizatora (Pt/C) je primenjena modifikovana poliol metoda iz rastvora etilen glikola, dok je kao nosač korišćen ugljenični kriogel. Katalizator je okarakterisan primenom BET metode, difrakcije X-zraka (XRD) i transmisione elektronske mikroskopije (TEM). Kinetika reakcije redukcije kiseonika ispitivana je korišćenjem stacionarne polarizacione metode i metode ciklične voltametrije. Oblast malih gustina struje, na svim teperaturama, na krivoj polarizacije, karakteriše vrednost Tafelovog nagiba od -2.3RT/F, dok je u oblasti visokih gustina struje vrednost ovog nagiba -2.3x2RT/F. Određene su vrednosti prividne entalpije aktivacije na konstantnim potencijalima, za obe oblasti gustina struja, i njihova razlika iskazana za nulu Galvanijeve razlike potencijala. Potvrđeno je da je mehanizam redukcije kiseonika, kao i stupanj koji određuje ukupnu brzinu reakcije isti u obe oblasti gustina struja, a da je razlika u kinetici reakcije posledica razlike u zavisnosti adsorpcije reakcionih intermedijara od potencijala. Poređenjem katalitičke aktivnosti, izražene preko gustine struje po realnoj površini katalizatora, konstatovana je nešto veća aktivnost Pt/C katalizatora u odnosu na polikristalnu Pt.
PB  - Serbian Chemical Society, Belgrade
T2  - Journal of the Serbian Chemical Society
T1  - Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles
T1  - Temperaturna zavisnost elektrohemijske redukcije kiseonika na nanočesticama platine na ugljeničnom nosaču
EP  - 654
IS  - 6
SP  - 641
VL  - 73
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1346
ER  - 

@article{
author = "Elezović, Nevenka R. and Babić, Biljana M. and Krstajić, Nedeljko V. and Gojković, Snežana Lj. and Vračar, Ljiljana M.",
year = "2008",
abstract = "The temperature dependence of oxygen reduction reaction (ORR) was studied on highly dispersed Pt nanoparticles supported on a carbon cryo-gel. The specific surface area of the support was 517 m2 g-1, the Pt particles diameter was about 2.7 nm and the loading of the catalyst was 20 wt.%. The kinetics of the ORR at the Pt/C electrode was examined in 0.50 mol dm-3 HClO4 solution in the temperature range from 274 to 318 K. At all temperatures, two distinct E-log j regions were observed; at low current densities with a slope of -2.3RT/F and at high current densities with a slope of -2.3´2RT/F. In order to confirm the mechanism of oxygen reduction previously suggested at a polycrystalline Pt and a Pt/Ebonex nanostructured electrode, the apparent enthalpies of activation at selected potentials vs. the reversible hydrogen electrode were calculated in both current density regions. Although ∆H ≠a,1  gt  ∆H ≠a,h , it was a,1 a, h found that the enthalpies of activation at the zero Galvani potential difference were the same and hence it could be concluded that the rate-determining step of the ORR was the same in both current density regions. The synthesized Pt/C catalyst showed a small enhancement in the catalytic activity for ORR in comparison to the polycrystalline Pt, but no change in the mechanism of the reaction., Kinetika reakcije redukcije kiseonika je ispitivana na nanočesticama platine dispergovanim na ugljeničnom nosaču, u 0,50 mol dm-3 HClO4, u temperaturnom intervalu od 278 do 318 K. Za sintezu Pt katalizatora (Pt/C) je primenjena modifikovana poliol metoda iz rastvora etilen glikola, dok je kao nosač korišćen ugljenični kriogel. Katalizator je okarakterisan primenom BET metode, difrakcije X-zraka (XRD) i transmisione elektronske mikroskopije (TEM). Kinetika reakcije redukcije kiseonika ispitivana je korišćenjem stacionarne polarizacione metode i metode ciklične voltametrije. Oblast malih gustina struje, na svim teperaturama, na krivoj polarizacije, karakteriše vrednost Tafelovog nagiba od -2.3RT/F, dok je u oblasti visokih gustina struje vrednost ovog nagiba -2.3x2RT/F. Određene su vrednosti prividne entalpije aktivacije na konstantnim potencijalima, za obe oblasti gustina struja, i njihova razlika iskazana za nulu Galvanijeve razlike potencijala. Potvrđeno je da je mehanizam redukcije kiseonika, kao i stupanj koji određuje ukupnu brzinu reakcije isti u obe oblasti gustina struja, a da je razlika u kinetici reakcije posledica razlike u zavisnosti adsorpcije reakcionih intermedijara od potencijala. Poređenjem katalitičke aktivnosti, izražene preko gustine struje po realnoj površini katalizatora, konstatovana je nešto veća aktivnost Pt/C katalizatora u odnosu na polikristalnu Pt.",
publisher = "Serbian Chemical Society, Belgrade",
journal = "Journal of the Serbian Chemical Society",
title = "Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles, Temperaturna zavisnost elektrohemijske redukcije kiseonika na nanočesticama platine na ugljeničnom nosaču",
pages = "654-641",
number = "6",
volume = "73",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1346"
}

Elezović, N. R., Babić, B. M., Krstajić, N. V., Gojković, S. Lj.,& Vračar, L. M.. (2008). Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles. in Journal of the Serbian Chemical Society
Serbian Chemical Society, Belgrade., 73(6), 641-654.
https://hdl.handle.net/21.15107/rcub_technorep_1346

Elezović NR, Babić BM, Krstajić NV, Gojković SL, Vračar LM. Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles. in Journal of the Serbian Chemical Society. 2008;73(6):641-654.
https://hdl.handle.net/21.15107/rcub_technorep_1346 .

Elezović, Nevenka R., Babić, Biljana M., Krstajić, Nedeljko V., Gojković, Snežana Lj., Vračar, Ljiljana M., "Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles" in Journal of the Serbian Chemical Society, 73, no. 6 (2008):641-654,
https://hdl.handle.net/21.15107/rcub_technorep_1346 .

TY  - JOUR
AU  - Jakšić, Jelena M.
AU  - Lačnjevac, Časlav M.
AU  - Krstajić, Nedeljko V.
AU  - Jakšić, Milan M.
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5562
AB  - The aim of the present paper has been to introduce the electron conductive and d-d-interactive individual and composite hypo-d-oxides of the increased altervalent capacity, or their suboxides (Magneli phases,), as catalytic supports and therefrom provide: (i) The Strong Metal-Support Interaction (SMSI) effect, and (ii) the Dynamic spillover interactive transfer of primary oxides (M-OH) for further electrode reactions, and thereby advance the overall electrocatalytic activity. The d-band has been pointed out as the bonding, adsorptive and catalytic orbital. In the same context, the phenomenon and significance of the d-d-correlations both in heterogeneous catalysis and electrocatalysis are displayed and inferred. Since hypo-d-oxides feature the exchange membrane properties, the higher the altervalent capacity, the higher the spillover effect. Potentiodynamic experiments have shown that the reversible peak of the primary oxide growth on Pt, Ru and Au supported upon hypo-d-oxides and suboxides becomes distinctly increased in the charge capacity and shifts to remarkably more negative potential values, so that it starts even within the range of H-adatoms desorption, while its rfeduction extends until and merge with the UPD of hydrogen atoms. With wet tungstenia doped titania supported Pt catalyst in membrane cells these peaks dramatically increase in their charge capacity and reversibly become shrunk with a decreased moisture content in the feeding inert gas mixture, and vice versa. Such distinct potentiodynamic scans, in conjunction with some broaden complementary kinetic electrocatalytic improvements rising from the same hypo-d-oxide and/or suboxide interactive support effects, have been proved to be the best and comparable experimental evidence for the spillover effect of primary oxides.
PB  - Serbian Chemical Society
T2  - Chemical Industry and Chemical Engineering Quarterly
T1  - Interactive supported electrocatalysts and spillover effect in electrocatalysis for hydrogen and oxygen electrode reactions
EP  - 136
IS  - 2
SP  - 119
VL  - 14
DO  - 10.2298/CICEQ0802119J
ER  - 

@article{
author = "Jakšić, Jelena M. and Lačnjevac, Časlav M. and Krstajić, Nedeljko V. and Jakšić, Milan M.",
year = "2008",
abstract = "The aim of the present paper has been to introduce the electron conductive and d-d-interactive individual and composite hypo-d-oxides of the increased altervalent capacity, or their suboxides (Magneli phases,), as catalytic supports and therefrom provide: (i) The Strong Metal-Support Interaction (SMSI) effect, and (ii) the Dynamic spillover interactive transfer of primary oxides (M-OH) for further electrode reactions, and thereby advance the overall electrocatalytic activity. The d-band has been pointed out as the bonding, adsorptive and catalytic orbital. In the same context, the phenomenon and significance of the d-d-correlations both in heterogeneous catalysis and electrocatalysis are displayed and inferred. Since hypo-d-oxides feature the exchange membrane properties, the higher the altervalent capacity, the higher the spillover effect. Potentiodynamic experiments have shown that the reversible peak of the primary oxide growth on Pt, Ru and Au supported upon hypo-d-oxides and suboxides becomes distinctly increased in the charge capacity and shifts to remarkably more negative potential values, so that it starts even within the range of H-adatoms desorption, while its rfeduction extends until and merge with the UPD of hydrogen atoms. With wet tungstenia doped titania supported Pt catalyst in membrane cells these peaks dramatically increase in their charge capacity and reversibly become shrunk with a decreased moisture content in the feeding inert gas mixture, and vice versa. Such distinct potentiodynamic scans, in conjunction with some broaden complementary kinetic electrocatalytic improvements rising from the same hypo-d-oxide and/or suboxide interactive support effects, have been proved to be the best and comparable experimental evidence for the spillover effect of primary oxides.",
publisher = "Serbian Chemical Society",
journal = "Chemical Industry and Chemical Engineering Quarterly",
title = "Interactive supported electrocatalysts and spillover effect in electrocatalysis for hydrogen and oxygen electrode reactions",
pages = "136-119",
number = "2",
volume = "14",
doi = "10.2298/CICEQ0802119J"
}

Jakšić, J. M., Lačnjevac, Č. M., Krstajić, N. V.,& Jakšić, M. M.. (2008). Interactive supported electrocatalysts and spillover effect in electrocatalysis for hydrogen and oxygen electrode reactions. in Chemical Industry and Chemical Engineering Quarterly
Serbian Chemical Society., 14(2), 119-136.
https://doi.org/10.2298/CICEQ0802119J

Jakšić JM, Lačnjevac ČM, Krstajić NV, Jakšić MM. Interactive supported electrocatalysts and spillover effect in electrocatalysis for hydrogen and oxygen electrode reactions. in Chemical Industry and Chemical Engineering Quarterly. 2008;14(2):119-136.
doi:10.2298/CICEQ0802119J .

Jakšić, Jelena M., Lačnjevac, Časlav M., Krstajić, Nedeljko V., Jakšić, Milan M., "Interactive supported electrocatalysts and spillover effect in electrocatalysis for hydrogen and oxygen electrode reactions" in Chemical Industry and Chemical Engineering Quarterly, 14, no. 2 (2008):119-136,
https://doi.org/10.2298/CICEQ0802119J . .