TY  - JOUR
AU  - Kutyła, Dawid
AU  - Krstajić Pajić, Mila N.
AU  - Lačnjevac, Uroš Č.
AU  - Marzec, Mateusz M.
AU  - Elezović, Nevenka R.
AU  - Żabiński, Piotr
PY  - 2024-02
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6992
AB  - This study investigates the structure, electrochemical behavior and hydrogen evolution reaction (HER) performance of electrodeposited Ru–Co alloy coatings. The alloys were prepared from a 0.75 M Co2+ + 0.025 M Ru3+ solution at various potentials ranging from −0.5 to −1.2 V vs. SCE. Results reveal that the Ru and Co deposition processes are interdependent. The deposition of nobler Ru from the mixed metal solution reaches pure diffusion control already at −0.7 V compared to −1.0 V from a single Ru bath. On the other hand, Co deposition is significantly facilitated in the presence of Ru in the solution. Consequently, as the deposition potential changes from −0.6 to −1.0 V, Ru–Co solid solution coatings characterized by a distinct globular morphology are formed, with their Co content increasing from 22.1/7.4 to 70.2/86.1 wt% for the Cu/Ti2AlC MAX phase substrate applied. The alloy catalysts are found to show much better HER activity and stability in alkaline than in acidic solutions. The best Ru–Co@Ti2AlC sample, electrodeposited at −0.6 V, requires an overpotential of only −95 mV to deliver a current density of −100 mA cm−2 in 1 M KOH, thus outperforming most Ru–Co-based HER electrocatalysts reported to date.
PB  - Elsevier Ltd.
T2  - International Journal of Hydrogen Energy
T1  - Ru–Co alloy coatings electrodeposited on a MAX phase substrate as efficient catalysts for the hydrogen evolution reaction
EP  - 40
SP  - 28
VL  - 56
DO  - 10.1016/j.ijhydene.2023.11.296
ER  - 

@article{
author = "Kutyła, Dawid and Krstajić Pajić, Mila N. and Lačnjevac, Uroš Č. and Marzec, Mateusz M. and Elezović, Nevenka R. and Żabiński, Piotr",
year = "2024-02",
abstract = "This study investigates the structure, electrochemical behavior and hydrogen evolution reaction (HER) performance of electrodeposited Ru–Co alloy coatings. The alloys were prepared from a 0.75 M Co2+ + 0.025 M Ru3+ solution at various potentials ranging from −0.5 to −1.2 V vs. SCE. Results reveal that the Ru and Co deposition processes are interdependent. The deposition of nobler Ru from the mixed metal solution reaches pure diffusion control already at −0.7 V compared to −1.0 V from a single Ru bath. On the other hand, Co deposition is significantly facilitated in the presence of Ru in the solution. Consequently, as the deposition potential changes from −0.6 to −1.0 V, Ru–Co solid solution coatings characterized by a distinct globular morphology are formed, with their Co content increasing from 22.1/7.4 to 70.2/86.1 wt% for the Cu/Ti2AlC MAX phase substrate applied. The alloy catalysts are found to show much better HER activity and stability in alkaline than in acidic solutions. The best Ru–Co@Ti2AlC sample, electrodeposited at −0.6 V, requires an overpotential of only −95 mV to deliver a current density of −100 mA cm−2 in 1 M KOH, thus outperforming most Ru–Co-based HER electrocatalysts reported to date.",
publisher = "Elsevier Ltd.",
journal = "International Journal of Hydrogen Energy",
title = "Ru–Co alloy coatings electrodeposited on a MAX phase substrate as efficient catalysts for the hydrogen evolution reaction",
pages = "40-28",
volume = "56",
doi = "10.1016/j.ijhydene.2023.11.296"
}

Kutyła, D., Krstajić Pajić, M. N., Lačnjevac, U. Č., Marzec, M. M., Elezović, N. R.,& Żabiński, P.. (2024-02). Ru–Co alloy coatings electrodeposited on a MAX phase substrate as efficient catalysts for the hydrogen evolution reaction. in International Journal of Hydrogen Energy
Elsevier Ltd.., 56, 28-40.
https://doi.org/10.1016/j.ijhydene.2023.11.296

Kutyła D, Krstajić Pajić MN, Lačnjevac UČ, Marzec MM, Elezović NR, Żabiński P. Ru–Co alloy coatings electrodeposited on a MAX phase substrate as efficient catalysts for the hydrogen evolution reaction. in International Journal of Hydrogen Energy. 2024;56:28-40.
doi:10.1016/j.ijhydene.2023.11.296 .

Kutyła, Dawid, Krstajić Pajić, Mila N., Lačnjevac, Uroš Č., Marzec, Mateusz M., Elezović, Nevenka R., Żabiński, Piotr, "Ru–Co alloy coatings electrodeposited on a MAX phase substrate as efficient catalysts for the hydrogen evolution reaction" in International Journal of Hydrogen Energy, 56 (2024-02):28-40,
https://doi.org/10.1016/j.ijhydene.2023.11.296 . .

TY  - JOUR
AU  - Gojgić, Jelena D.
AU  - Petričević, Aleksandar M.
AU  - Krstajić Pajić, Mila N.
AU  - Jović, Vladimir D.
PY  - 2024
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7409
AB  - The example of the procedure for the correct determination of the parameters of hydrogen evolution reaction (HER), the exchange current density (jo) and relaxation time (τo) for intermediate (adsorbed hydrogen, Hads) adsorption at modified porous Ni-based electrode are presented in this work. Such a procedure is applicable for the HER at all electrode materials. The value of jo was obtained from the intercept at η = 0 mV from the η vs. log (Rct-1) dependence (η-overpotential), while the value of τo was obtained from the intercept at η = 0 mV from the logτ vs. η dependence. It was shown that for the correct determination of jo and τo, it is necessary to correct applied η for the jRs drop, by recording current density (j) for applied η and correcting it for jRs.
AB  - Na primeru izdvajanja vodonika na Ni-Sn/Ni pena 800 elektrodi u ovom radu je prikazana procedura korektnog određivanja parametara ove reakcije, a to su: gustina struje izmene (jo) i relaksaciono vreme adsorpcije intermedijara () (Hads). Vrednost jo je određena iz odsečka za  = 0 mV zavisnosti  vs. log(Rct-1 ) ( - prenapetost), dok je vrednost o određena iz odsečka za  = 0 mV zavisnosti log vs. . Pokazano je da je za korektno određivanje ovih parametara neophodno korigovati gustinu struje pri svakoj zadatoj prenapetosti za vrednost omskog pada napona jRs.
PB  - Inženjersko društvo za koroziju
T2  - Zaštita materijala
T1  - Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer
T1  - Procedura korektnog određivanja parametara reakcije izdvajanja vodonika na elektrodi od Ni pene modifikovane elektrohemijski istaloženom Ni-Sn legurom
EP  - 10
IS  - 1
SP  - 3
VL  - 65
DO  - 10.62638/zasmat1039
ER  - 

@article{
author = "Gojgić, Jelena D. and Petričević, Aleksandar M. and Krstajić Pajić, Mila N. and Jović, Vladimir D.",
year = "2024",
abstract = "The example of the procedure for the correct determination of the parameters of hydrogen evolution reaction (HER), the exchange current density (jo) and relaxation time (τo) for intermediate (adsorbed hydrogen, Hads) adsorption at modified porous Ni-based electrode are presented in this work. Such a procedure is applicable for the HER at all electrode materials. The value of jo was obtained from the intercept at η = 0 mV from the η vs. log (Rct-1) dependence (η-overpotential), while the value of τo was obtained from the intercept at η = 0 mV from the logτ vs. η dependence. It was shown that for the correct determination of jo and τo, it is necessary to correct applied η for the jRs drop, by recording current density (j) for applied η and correcting it for jRs., Na primeru izdvajanja vodonika na Ni-Sn/Ni pena 800 elektrodi u ovom radu je prikazana procedura korektnog određivanja parametara ove reakcije, a to su: gustina struje izmene (jo) i relaksaciono vreme adsorpcije intermedijara () (Hads). Vrednost jo je određena iz odsečka za  = 0 mV zavisnosti  vs. log(Rct-1 ) ( - prenapetost), dok je vrednost o određena iz odsečka za  = 0 mV zavisnosti log vs. . Pokazano je da je za korektno određivanje ovih parametara neophodno korigovati gustinu struje pri svakoj zadatoj prenapetosti za vrednost omskog pada napona jRs.",
publisher = "Inženjersko društvo za koroziju",
journal = "Zaštita materijala",
title = "Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer, Procedura korektnog određivanja parametara reakcije izdvajanja vodonika na elektrodi od Ni pene modifikovane elektrohemijski istaloženom Ni-Sn legurom",
pages = "10-3",
number = "1",
volume = "65",
doi = "10.62638/zasmat1039"
}

Gojgić, J. D., Petričević, A. M., Krstajić Pajić, M. N.,& Jović, V. D.. (2024). Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer. in Zaštita materijala
Inženjersko društvo za koroziju., 65(1), 3-10.
https://doi.org/10.62638/zasmat1039

Gojgić JD, Petričević AM, Krstajić Pajić MN, Jović VD. Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer. in Zaštita materijala. 2024;65(1):3-10.
doi:10.62638/zasmat1039 .

Gojgić, Jelena D., Petričević, Aleksandar M., Krstajić Pajić, Mila N., Jović, Vladimir D., "Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer" in Zaštita materijala, 65, no. 1 (2024):3-10,
https://doi.org/10.62638/zasmat1039 . .

TY  - JOUR
AU  - Gojgić, Jelena D.
AU  - Petričević, Aleksandar M.
AU  - Rauscher, Thomas
AU  - Bernäcker, Christian I.
AU  - Weißgärber, Thomas
AU  - Pavko, Luka
AU  - Vasilić, Rastko
AU  - Krstajić Pajić, Mila N.
AU  - Jović, Vladimir D.
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6577
AB  - The hydrogen evolution reaction (HER) was investigated in 1.0 M KOH at 25 °C at Ni foams with different pore sizes (450–1200 µm), and at the Ni-Sn/Ni foam electrodes, where Ni-Sn alloys were electrodeposited from the pyrophosphate-glycine bath using controlled potential coulometry (CPC) technique. The cross-section analysis revealed that rough Ni-Sn alloy covers complete available inner and outer foam surface, while investigated coating composition varied from 62 to 80 at% Ni (20–38 at% Sn). Comparing the HER polarization curves, the overpotential at j = −200 mA cm−2 was 427 mV lower for Ni-Sn samples than for bare Ni foams, while Tafel slopes changed from − 120 mV dec−1 at bare Ni foams to − 50 mV dec−1 for Ni-Sn/Ni foam samples. The lowest overpotential at − 100 mA cm−2 achieved is as low as − 77 mV. These cathodes could be promising 3D materials for industrial water electrolysis in zero-gap membrane flow cells.
PB  - Elsevier B.V.
T2  - Applied Catalysis A: General
T1  - Hydrogen evolution at Ni foam electrodes and Ni-Sn coated Ni foam electrodes
SP  - 119312
VL  - 663
DO  - 10.1016/j.apcata.2023.119312
ER  - 

@article{
author = "Gojgić, Jelena D. and Petričević, Aleksandar M. and Rauscher, Thomas and Bernäcker, Christian I. and Weißgärber, Thomas and Pavko, Luka and Vasilić, Rastko and Krstajić Pajić, Mila N. and Jović, Vladimir D.",
year = "2023",
abstract = "The hydrogen evolution reaction (HER) was investigated in 1.0 M KOH at 25 °C at Ni foams with different pore sizes (450–1200 µm), and at the Ni-Sn/Ni foam electrodes, where Ni-Sn alloys were electrodeposited from the pyrophosphate-glycine bath using controlled potential coulometry (CPC) technique. The cross-section analysis revealed that rough Ni-Sn alloy covers complete available inner and outer foam surface, while investigated coating composition varied from 62 to 80 at% Ni (20–38 at% Sn). Comparing the HER polarization curves, the overpotential at j = −200 mA cm−2 was 427 mV lower for Ni-Sn samples than for bare Ni foams, while Tafel slopes changed from − 120 mV dec−1 at bare Ni foams to − 50 mV dec−1 for Ni-Sn/Ni foam samples. The lowest overpotential at − 100 mA cm−2 achieved is as low as − 77 mV. These cathodes could be promising 3D materials for industrial water electrolysis in zero-gap membrane flow cells.",
publisher = "Elsevier B.V.",
journal = "Applied Catalysis A: General",
title = "Hydrogen evolution at Ni foam electrodes and Ni-Sn coated Ni foam electrodes",
pages = "119312",
volume = "663",
doi = "10.1016/j.apcata.2023.119312"
}

Gojgić, J. D., Petričević, A. M., Rauscher, T., Bernäcker, C. I., Weißgärber, T., Pavko, L., Vasilić, R., Krstajić Pajić, M. N.,& Jović, V. D.. (2023). Hydrogen evolution at Ni foam electrodes and Ni-Sn coated Ni foam electrodes. in Applied Catalysis A: General
Elsevier B.V.., 663, 119312.
https://doi.org/10.1016/j.apcata.2023.119312

Gojgić JD, Petričević AM, Rauscher T, Bernäcker CI, Weißgärber T, Pavko L, Vasilić R, Krstajić Pajić MN, Jović VD. Hydrogen evolution at Ni foam electrodes and Ni-Sn coated Ni foam electrodes. in Applied Catalysis A: General. 2023;663:119312.
doi:10.1016/j.apcata.2023.119312 .

Gojgić, Jelena D., Petričević, Aleksandar M., Rauscher, Thomas, Bernäcker, Christian I., Weißgärber, Thomas, Pavko, Luka, Vasilić, Rastko, Krstajić Pajić, Mila N., Jović, Vladimir D., "Hydrogen evolution at Ni foam electrodes and Ni-Sn coated Ni foam electrodes" in Applied Catalysis A: General, 663 (2023):119312,
https://doi.org/10.1016/j.apcata.2023.119312 . .

TY  - JOUR
AU  - Krstajić Pajić, Mila N.
AU  - Dobrota, Ana S.
AU  - Mazare, Anca
AU  - Đurđić, Slađana
AU  - Hwang, Imgon
AU  - Skorodumova, Natalia V.
AU  - Manojlović, Dragan
AU  - Vasilić, Rastko
AU  - Pašti, Igor A.
AU  - Schmuki, Patrik
AU  - Lačnjevac, Uroš
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6576
AB  - Efficient cathodes for the hydrogen evolution reaction (HER) in acidic water electrolysis rely on the use of expensive platinum group metals (PGMs). However, to achieve economically viable operation, both the content of PGMs must be reduced and their intrinsically strong H adsorption mitigated. Herein, we show that the surface effects of hydrogenated TiO2 nanotube (TNT) arrays can make osmium, a so far less-explored PGM, a highly active HER electrocatalyst. These defect-rich TiO2 nanostructures provide an interactive scaffold for the galvanic deposition of Os particles with modulated adsorption properties. Through systematic investigations, we identify the synthesis conditions (OsCl3 concentration/temperature/reaction time) that yield a progressive improvement in Os deposition rate and mass loading, thereby decreasing the HER overpotential. At the same time, the Os particles deposited by this procedure remain mainly sub-nanometric and entirely cover the inner tube walls. An optimally balanced Os@TNT composite prepared at 3 mM/55 °C/30 min exhibits a record low overpotential (η) of 61 mV at a current density of 100 mA cm-2, a high mass activity of 20.8 A mgOs-1 at 80 mV, and a stable performance in an acidic medium. Density functional theory calculations indicate the existence of strong interactions between the hydrogenated TiO2 surface and small Os clusters, which may weaken the Os-H* binding strength and thus boost the intrinsic HER activity of Os centers. The results presented in this study offer new directions for the fabrication of cost-effective PGM-based catalysts and a better understanding of the synergistic electronic interactions at the PGM|TiO2 interface.
PB  - American Chemical Society
T1  - Activation of Osmium by the Surface Effects of Hydrogenated TiO2 Nanotube Arrays for Enhanced Hydrogen Evolution Reaction Performance
EP  - 31469
IS  - 26
SP  - 31459
VL  - 15
DO  - 10.1021/acsami.3c04498
ER  - 

@article{
author = "Krstajić Pajić, Mila N. and Dobrota, Ana S. and Mazare, Anca and Đurđić, Slađana and Hwang, Imgon and Skorodumova, Natalia V. and Manojlović, Dragan and Vasilić, Rastko and Pašti, Igor A. and Schmuki, Patrik and Lačnjevac, Uroš",
year = "2023",
abstract = "Efficient cathodes for the hydrogen evolution reaction (HER) in acidic water electrolysis rely on the use of expensive platinum group metals (PGMs). However, to achieve economically viable operation, both the content of PGMs must be reduced and their intrinsically strong H adsorption mitigated. Herein, we show that the surface effects of hydrogenated TiO2 nanotube (TNT) arrays can make osmium, a so far less-explored PGM, a highly active HER electrocatalyst. These defect-rich TiO2 nanostructures provide an interactive scaffold for the galvanic deposition of Os particles with modulated adsorption properties. Through systematic investigations, we identify the synthesis conditions (OsCl3 concentration/temperature/reaction time) that yield a progressive improvement in Os deposition rate and mass loading, thereby decreasing the HER overpotential. At the same time, the Os particles deposited by this procedure remain mainly sub-nanometric and entirely cover the inner tube walls. An optimally balanced Os@TNT composite prepared at 3 mM/55 °C/30 min exhibits a record low overpotential (η) of 61 mV at a current density of 100 mA cm-2, a high mass activity of 20.8 A mgOs-1 at 80 mV, and a stable performance in an acidic medium. Density functional theory calculations indicate the existence of strong interactions between the hydrogenated TiO2 surface and small Os clusters, which may weaken the Os-H* binding strength and thus boost the intrinsic HER activity of Os centers. The results presented in this study offer new directions for the fabrication of cost-effective PGM-based catalysts and a better understanding of the synergistic electronic interactions at the PGM|TiO2 interface.",
publisher = "American Chemical Society",
title = "Activation of Osmium by the Surface Effects of Hydrogenated TiO2 Nanotube Arrays for Enhanced Hydrogen Evolution Reaction Performance",
pages = "31469-31459",
number = "26",
volume = "15",
doi = "10.1021/acsami.3c04498"
}

Krstajić Pajić, M. N., Dobrota, A. S., Mazare, A., Đurđić, S., Hwang, I., Skorodumova, N. V., Manojlović, D., Vasilić, R., Pašti, I. A., Schmuki, P.,& Lačnjevac, U.. (2023). Activation of Osmium by the Surface Effects of Hydrogenated TiO2 Nanotube Arrays for Enhanced Hydrogen Evolution Reaction Performance. 
American Chemical Society., 15(26), 31459-31469.
https://doi.org/10.1021/acsami.3c04498

Krstajić Pajić MN, Dobrota AS, Mazare A, Đurđić S, Hwang I, Skorodumova NV, Manojlović D, Vasilić R, Pašti IA, Schmuki P, Lačnjevac U. Activation of Osmium by the Surface Effects of Hydrogenated TiO2 Nanotube Arrays for Enhanced Hydrogen Evolution Reaction Performance. 2023;15(26):31459-31469.
doi:10.1021/acsami.3c04498 .

Krstajić Pajić, Mila N., Dobrota, Ana S., Mazare, Anca, Đurđić, Slađana, Hwang, Imgon, Skorodumova, Natalia V., Manojlović, Dragan, Vasilić, Rastko, Pašti, Igor A., Schmuki, Patrik, Lačnjevac, Uroš, "Activation of Osmium by the Surface Effects of Hydrogenated TiO2 Nanotube Arrays for Enhanced Hydrogen Evolution Reaction Performance", 15, no. 26 (2023):31459-31469,
https://doi.org/10.1021/acsami.3c04498 . .

TY  - JOUR
AU  - Petričević, Aleksandar
AU  - Jović, Vladimir D.
AU  - Krstajić Pajić, Mila N.
AU  - Zabinski, Piotr
AU  - Elezović, Nevenka R.
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5353
AB  - Catalytic activity towards the oxygen reduction reaction (ORR) in 0.5 M H2SO4 was investigated at sub-monolayers and ultra-thin layers (corresponding to 10, 30 and 100 monolayers, (MLs)) of Pt electrochemically deposited on (Nb-Ti)2AlC substrate. Electrochemical deposition of Pt layers on (Nb-Ti)2AlC substrate was achieved from the solution containing 3 mM K2PtCl4 + 0.5 M NaCl (pH 4) under the conditions of convective diffusion (RPM = 400) using linear sweep voltammetry (LSV) at a sweep rate of 2 mV s-1, by determining limiting potential for deposition of each Pt sample from the QPt vs. E curves. The Pt samples were characterized X-ray photoelectron spectroscopy (XPS). XPS analysis showed that practically the whole surface of (Nb-Ti)2AlC substrate is covered with homogeneous layer of Pt, while Pt ion reduction was complete to metallic form – Pt(0) valence state. Then oxygen reduction was studied at rotating disc electrode by cyclic voltammetry and linear sweep voltammetry. Two different Tafel slopes were observed, one close to 60 mV dec-1 in low current densities region and second one ~ 120 mV dec-1 in high current densities region. This novel catalyst exhibited higher activity in comparison to carbon supported one, in terms of mass activity – kinetic current density normalized to Pt loading.
AB  - Ispitivana je reakcija redukcije kiseonika na tankim slojevima platine u 0.5 mol dm-3 H2SO4. Tanki
slojevi platine – čija količina naelektrisanja odgovara 10, 30 i 100 teorijskih monoslojeva Pt su
istaloženi na nosaču od (Nb-Ti)2AlC. Za elektrohemijsko taloženje je korišćen rastvor 3 mM
K2PtCl4 + 0.5 M NaCl pH = 4, u uslovima konvektivne difuzije (RPM = 400) primenom metode
linearne skenirajuće voltametrije (LSV) pri brzini promene potencijala od 2 mV s-1
. Elektrohemijski
dobijeni platinski katalizatori na pomenutom nosaču su okarakterisani metodom fotoelektronske
spektroskopija X-zraka (XPS), kao i elektrohemijskim tehnikama.
Za određivanje realne elektrohemijski aktivne površine elektrode je primenjena ciklična
voltametrija, integracijom ispod anodnog dela voltamograma u oblasti adsorpcije vodonika na
potpotencijalima. Za ispitivanje kinetike reakcije redukcije kiseonika je korišćena metoda linearne
skenirajuće voltametrije na rotirajućoj disk elektrodi. Dobijene su dve vrednosti Tafelovog nagiba,
jedna približno 60 mV dek-1
u oblasti malih prenapetosti, a druga ~ 120 mV dek-1
, u oblasti većih
gustina struje. Katalitička aktivnost katalizatora je poređena sa vrednostima iz literature dobijenim
na platini na ugljeničim nosačima na 0.85 V prema reverzibilnoj vodoničnoj elektrodi, izražena kao
kinetička gustina struje po realnoj površini electrode, ili specifična aktivnost – izražena kao
kinetička gustina struje po masi platine. Pokazano je da katalizator sa 10 monoslojeva platine
poseduje veoma dobru katalitičku aktivnost, posebno izraženu po masi istaložene platine.
PB  - Engineers Society for Corrosion
T2  - Zaštita materijala
T1  - Oxygen reduction reaction on electrochemically deposited sub-monolayers and ultra-thin layers of Pt on (Nb-Ti)2AlC substrate
T1  - Reakcija redukcije kiseonika na elektrohemijski istaloženim tankim slojevima platine na (Nb-Ti)2alc nosaču
EP  - 164
IS  - 2
SP  - 153
VL  - 63
DO  - 10.5937/zasmat2202153P
ER  - 

@article{
author = "Petričević, Aleksandar and Jović, Vladimir D. and Krstajić Pajić, Mila N. and Zabinski, Piotr and Elezović, Nevenka R.",
year = "2022",
abstract = "Catalytic activity towards the oxygen reduction reaction (ORR) in 0.5 M H2SO4 was investigated at sub-monolayers and ultra-thin layers (corresponding to 10, 30 and 100 monolayers, (MLs)) of Pt electrochemically deposited on (Nb-Ti)2AlC substrate. Electrochemical deposition of Pt layers on (Nb-Ti)2AlC substrate was achieved from the solution containing 3 mM K2PtCl4 + 0.5 M NaCl (pH 4) under the conditions of convective diffusion (RPM = 400) using linear sweep voltammetry (LSV) at a sweep rate of 2 mV s-1, by determining limiting potential for deposition of each Pt sample from the QPt vs. E curves. The Pt samples were characterized X-ray photoelectron spectroscopy (XPS). XPS analysis showed that practically the whole surface of (Nb-Ti)2AlC substrate is covered with homogeneous layer of Pt, while Pt ion reduction was complete to metallic form – Pt(0) valence state. Then oxygen reduction was studied at rotating disc electrode by cyclic voltammetry and linear sweep voltammetry. Two different Tafel slopes were observed, one close to 60 mV dec-1 in low current densities region and second one ~ 120 mV dec-1 in high current densities region. This novel catalyst exhibited higher activity in comparison to carbon supported one, in terms of mass activity – kinetic current density normalized to Pt loading., Ispitivana je reakcija redukcije kiseonika na tankim slojevima platine u 0.5 mol dm-3 H2SO4. Tanki
slojevi platine – čija količina naelektrisanja odgovara 10, 30 i 100 teorijskih monoslojeva Pt su
istaloženi na nosaču od (Nb-Ti)2AlC. Za elektrohemijsko taloženje je korišćen rastvor 3 mM
K2PtCl4 + 0.5 M NaCl pH = 4, u uslovima konvektivne difuzije (RPM = 400) primenom metode
linearne skenirajuće voltametrije (LSV) pri brzini promene potencijala od 2 mV s-1
. Elektrohemijski
dobijeni platinski katalizatori na pomenutom nosaču su okarakterisani metodom fotoelektronske
spektroskopija X-zraka (XPS), kao i elektrohemijskim tehnikama.
Za određivanje realne elektrohemijski aktivne površine elektrode je primenjena ciklična
voltametrija, integracijom ispod anodnog dela voltamograma u oblasti adsorpcije vodonika na
potpotencijalima. Za ispitivanje kinetike reakcije redukcije kiseonika je korišćena metoda linearne
skenirajuće voltametrije na rotirajućoj disk elektrodi. Dobijene su dve vrednosti Tafelovog nagiba,
jedna približno 60 mV dek-1
u oblasti malih prenapetosti, a druga ~ 120 mV dek-1
, u oblasti većih
gustina struje. Katalitička aktivnost katalizatora je poređena sa vrednostima iz literature dobijenim
na platini na ugljeničim nosačima na 0.85 V prema reverzibilnoj vodoničnoj elektrodi, izražena kao
kinetička gustina struje po realnoj površini electrode, ili specifična aktivnost – izražena kao
kinetička gustina struje po masi platine. Pokazano je da katalizator sa 10 monoslojeva platine
poseduje veoma dobru katalitičku aktivnost, posebno izraženu po masi istaložene platine.",
publisher = "Engineers Society for Corrosion",
journal = "Zaštita materijala",
title = "Oxygen reduction reaction on electrochemically deposited sub-monolayers and ultra-thin layers of Pt on (Nb-Ti)2AlC substrate, Reakcija redukcije kiseonika na elektrohemijski istaloženim tankim slojevima platine na (Nb-Ti)2alc nosaču",
pages = "164-153",
number = "2",
volume = "63",
doi = "10.5937/zasmat2202153P"
}

Petričević, A., Jović, V. D., Krstajić Pajić, M. N., Zabinski, P.,& Elezović, N. R.. (2022). Oxygen reduction reaction on electrochemically deposited sub-monolayers and ultra-thin layers of Pt on (Nb-Ti)2AlC substrate. in Zaštita materijala
Engineers Society for Corrosion., 63(2), 153-164.
https://doi.org/10.5937/zasmat2202153P

Petričević A, Jović VD, Krstajić Pajić MN, Zabinski P, Elezović NR. Oxygen reduction reaction on electrochemically deposited sub-monolayers and ultra-thin layers of Pt on (Nb-Ti)2AlC substrate. in Zaštita materijala. 2022;63(2):153-164.
doi:10.5937/zasmat2202153P .

Petričević, Aleksandar, Jović, Vladimir D., Krstajić Pajić, Mila N., Zabinski, Piotr, Elezović, Nevenka R., "Oxygen reduction reaction on electrochemically deposited sub-monolayers and ultra-thin layers of Pt on (Nb-Ti)2AlC substrate" in Zaštita materijala, 63, no. 2 (2022):153-164,
https://doi.org/10.5937/zasmat2202153P . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Zabinski, P.
AU  - Lačnjevac, Uroš
AU  - Krstajić-Pajić, Mila
AU  - Jović, V. D.
PY  - 2021
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/10
AB  - Two types of iridium oxide films formed at the Ti-2 AlC substrate were investigated: (1) anodically electrodeposited iridium oxide film from the solution based on IrCl(3)xH(2)O; (2) iridium oxide film prepared by cycling thin layer of electrodeposited Ir in the 0.5 M H2SO4 from - 0.25 to 1.20 V. It was shown that during anodic electrodeposition of iridium oxide film (1) coulombic efficiency decreases with increasing anodic potential, being only 3% atE = 0.7 V vs. SCE and 26% atE = 0.62 V vs. SCE. A pair of peaks corresponding to the transition Ir(III)-oxide/Ir(IV)-oxide was present on the CVs recorded in 0.5 M H2SO4. While cycling pure Ir thin layer in the solution of 0.5 M H2SO4 from - 0.25 to 1.20 V (2) up to 100 cycles, typical CV response was characterized with the prepeak and a pair of peaks corresponding to the Ir(III)/Ir(IV)-oxide transition. With the increase of cycles number to 150, additional peak at potential of 1.0 V appeared. This peak was formed on the account of pair of peaks corresponding to the Ir(III)/Ir(IV)-oxide transition. The oxygen evolution reaction (OER) was investigated at both iridium oxide films. It was shown that the Tafel slope for the OER was similar to 40 mV dec(-1)for the first polarization curve, confirming that the rds was a reaction S-OH - gt  S-O-ads + H++ e(-). As the number of recorded polarization curves increased, the activity of both types of iridium oxide films decreased, due to dissolution of iridium oxide films at the potentials of the OER. It is shown that anodically electrodeposited iridium oxide film is more active for the OER than that obtained by cycling electrodeposited iridium layer. However, both iridium oxide films exhibited insufficient stability.
PB  - Springer, New York
T2  - Journal of Solid State Electrochemistry
T1  - Electrochemical deposition and characterization of iridium oxide films on Ti2AlC support for oxygen evolution reaction
EP  - 363
IS  - 1
SP  - 351
VL  - 25
DO  - 10.1007/s10008-020-04816-7
ER  - 

@article{
author = "Elezović, Nevenka R. and Zabinski, P. and Lačnjevac, Uroš and Krstajić-Pajić, Mila and Jović, V. D.",
year = "2021",
abstract = "Two types of iridium oxide films formed at the Ti-2 AlC substrate were investigated: (1) anodically electrodeposited iridium oxide film from the solution based on IrCl(3)xH(2)O; (2) iridium oxide film prepared by cycling thin layer of electrodeposited Ir in the 0.5 M H2SO4 from - 0.25 to 1.20 V. It was shown that during anodic electrodeposition of iridium oxide film (1) coulombic efficiency decreases with increasing anodic potential, being only 3% atE = 0.7 V vs. SCE and 26% atE = 0.62 V vs. SCE. A pair of peaks corresponding to the transition Ir(III)-oxide/Ir(IV)-oxide was present on the CVs recorded in 0.5 M H2SO4. While cycling pure Ir thin layer in the solution of 0.5 M H2SO4 from - 0.25 to 1.20 V (2) up to 100 cycles, typical CV response was characterized with the prepeak and a pair of peaks corresponding to the Ir(III)/Ir(IV)-oxide transition. With the increase of cycles number to 150, additional peak at potential of 1.0 V appeared. This peak was formed on the account of pair of peaks corresponding to the Ir(III)/Ir(IV)-oxide transition. The oxygen evolution reaction (OER) was investigated at both iridium oxide films. It was shown that the Tafel slope for the OER was similar to 40 mV dec(-1)for the first polarization curve, confirming that the rds was a reaction S-OH - gt  S-O-ads + H++ e(-). As the number of recorded polarization curves increased, the activity of both types of iridium oxide films decreased, due to dissolution of iridium oxide films at the potentials of the OER. It is shown that anodically electrodeposited iridium oxide film is more active for the OER than that obtained by cycling electrodeposited iridium layer. However, both iridium oxide films exhibited insufficient stability.",
publisher = "Springer, New York",
journal = "Journal of Solid State Electrochemistry",
title = "Electrochemical deposition and characterization of iridium oxide films on Ti2AlC support for oxygen evolution reaction",
pages = "363-351",
number = "1",
volume = "25",
doi = "10.1007/s10008-020-04816-7"
}

Elezović, N. R., Zabinski, P., Lačnjevac, U., Krstajić-Pajić, M.,& Jović, V. D.. (2021). Electrochemical deposition and characterization of iridium oxide films on Ti2AlC support for oxygen evolution reaction. in Journal of Solid State Electrochemistry
Springer, New York., 25(1), 351-363.
https://doi.org/10.1007/s10008-020-04816-7

Elezović NR, Zabinski P, Lačnjevac U, Krstajić-Pajić M, Jović VD. Electrochemical deposition and characterization of iridium oxide films on Ti2AlC support for oxygen evolution reaction. in Journal of Solid State Electrochemistry. 2021;25(1):351-363.
doi:10.1007/s10008-020-04816-7 .

Elezović, Nevenka R., Zabinski, P., Lačnjevac, Uroš, Krstajić-Pajić, Mila, Jović, V. D., "Electrochemical deposition and characterization of iridium oxide films on Ti2AlC support for oxygen evolution reaction" in Journal of Solid State Electrochemistry, 25, no. 1 (2021):351-363,
https://doi.org/10.1007/s10008-020-04816-7 . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Krstajić-Pajić, Mila
AU  - Jović, Vladimir D.
PY  - 2020
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4551
AB  - The hydrogen evolution reaction (HER) was investigated at sub-monolayers of iridium electrodeposited on Ti2AlC substrate. The lowest amount of electrodeposited iridium was 3 close-packed (111) monolayers (3 ML), while the highest one was 22 ML (3, 5, 10, 15 and 22 ML). The lowest and the highest amounts of iridium were electrodeposited by linear sweep voltammetry (LSV), while the other three samples were electrodeposited by controlled potential coulometry, from the solution containing 1 mM, or 3 mM K3IrCl6 + 0.5 M Na2SO4 (pH 6.2) at 70 °C. The HER was investigated by polarization and electrochemical impedance spectroscopy (EIS) measurements. Polarization curves for iridium sub-monolayers equal, or higher than 6 ML showed low Tafel slope of -14 to -16 mV dec-1 up to about -0.1 A cm-2, while at higher current densities the Tafel slopes increased, varying between -40 and -72 mV dec-1. The highest value of exchange current density (jo) was obtained for 6 ML of electrodeposited iridium, being -27.89 A g-1. The overpotential at j = -0.3 A cm-2 could be determined for samples containing 15 ML and 22 ML of iridium, being 82 mV.
AB  - Izdvajanje vodonika ispitivano je u rastvoru sumporne kiseline na elektrohemijski istaloženim slojevima (od 3 monosloja do 22 monosloja) iridijuma na podlozi od Ti2AlC. Najmanja i najveća količina iridijuma (3 i 22 monosloja) elektrohemijski su istaložene metodom linearne voltametrije, dok su preostala tri uzorka (6, 10 i 15 monoslojeva) elektrohemijski istaložena pri konstantnom potencijalu do potrebne količine naelektrisanja iz rastvora 1 mM, ili 3 mM K3IrCl6 + 0.5 M Na2SO4 (pH 6.2) na temperaturi rastvora od 70 °C. Reakcija izdvajanja vodonika ispitivana je na svim elektrodama snimanjem polarizacionih krivih. Za uzorak sa 22 monosloja Ir primenjena je i metoda impedanse. Polarizacione krive za uzorke sa 6, 10, 15 i 22 monosloja Ir bile su okarakterisane malom vrednošću Tafel-ovog nagiba od -14 to -16 mV dek-1 u oblasti gustina struja do -0.1 A cm-2, dok se Tafel-ov nagib povećavao pri većim gustinama struja varirajući od -40 do -72 mV dek-1. Najveća vrednost specifične gustine struje izmene (jo) dobijena je kod uzorka sa 6 monoslojeva Ir i iznosila je - 27.89 A g-1. Za uzorke sa 15 i 22 monosloja Ir vrednost prenapetosti pri gustini struje j = -0.3 A cm-2 (uslovi industrijske proizvodnje vodonika) iznosila je 82 mV.
PB  - Engineering Society for Corrosion, Belgrade, Serbia
T2  - Zaštita materijala
T1  - Sub-monolayers of iridium electrodeposited on Ti2AlC substrate as catalysts for hydrogen evolution reaction in sulfuric acid solution
T1  - Nekoliko monoslojeva elektrohemijski istaloženog iridijuma na podlozi od Ti2AlC kao katalizatori za izdvajanje vodonika u rastvoru sumporne kiseline
EP  - 191
IS  - 3
SP  - 181
VL  - 61
DO  - 10.5937/zasmat2003181E
ER  - 

@article{
author = "Elezović, Nevenka R. and Krstajić-Pajić, Mila and Jović, Vladimir D.",
year = "2020",
abstract = "The hydrogen evolution reaction (HER) was investigated at sub-monolayers of iridium electrodeposited on Ti2AlC substrate. The lowest amount of electrodeposited iridium was 3 close-packed (111) monolayers (3 ML), while the highest one was 22 ML (3, 5, 10, 15 and 22 ML). The lowest and the highest amounts of iridium were electrodeposited by linear sweep voltammetry (LSV), while the other three samples were electrodeposited by controlled potential coulometry, from the solution containing 1 mM, or 3 mM K3IrCl6 + 0.5 M Na2SO4 (pH 6.2) at 70 °C. The HER was investigated by polarization and electrochemical impedance spectroscopy (EIS) measurements. Polarization curves for iridium sub-monolayers equal, or higher than 6 ML showed low Tafel slope of -14 to -16 mV dec-1 up to about -0.1 A cm-2, while at higher current densities the Tafel slopes increased, varying between -40 and -72 mV dec-1. The highest value of exchange current density (jo) was obtained for 6 ML of electrodeposited iridium, being -27.89 A g-1. The overpotential at j = -0.3 A cm-2 could be determined for samples containing 15 ML and 22 ML of iridium, being 82 mV., Izdvajanje vodonika ispitivano je u rastvoru sumporne kiseline na elektrohemijski istaloženim slojevima (od 3 monosloja do 22 monosloja) iridijuma na podlozi od Ti2AlC. Najmanja i najveća količina iridijuma (3 i 22 monosloja) elektrohemijski su istaložene metodom linearne voltametrije, dok su preostala tri uzorka (6, 10 i 15 monoslojeva) elektrohemijski istaložena pri konstantnom potencijalu do potrebne količine naelektrisanja iz rastvora 1 mM, ili 3 mM K3IrCl6 + 0.5 M Na2SO4 (pH 6.2) na temperaturi rastvora od 70 °C. Reakcija izdvajanja vodonika ispitivana je na svim elektrodama snimanjem polarizacionih krivih. Za uzorak sa 22 monosloja Ir primenjena je i metoda impedanse. Polarizacione krive za uzorke sa 6, 10, 15 i 22 monosloja Ir bile su okarakterisane malom vrednošću Tafel-ovog nagiba od -14 to -16 mV dek-1 u oblasti gustina struja do -0.1 A cm-2, dok se Tafel-ov nagib povećavao pri većim gustinama struja varirajući od -40 do -72 mV dek-1. Najveća vrednost specifične gustine struje izmene (jo) dobijena je kod uzorka sa 6 monoslojeva Ir i iznosila je - 27.89 A g-1. Za uzorke sa 15 i 22 monosloja Ir vrednost prenapetosti pri gustini struje j = -0.3 A cm-2 (uslovi industrijske proizvodnje vodonika) iznosila je 82 mV.",
publisher = "Engineering Society for Corrosion, Belgrade, Serbia",
journal = "Zaštita materijala",
title = "Sub-monolayers of iridium electrodeposited on Ti2AlC substrate as catalysts for hydrogen evolution reaction in sulfuric acid solution, Nekoliko monoslojeva elektrohemijski istaloženog iridijuma na podlozi od Ti2AlC kao katalizatori za izdvajanje vodonika u rastvoru sumporne kiseline",
pages = "191-181",
number = "3",
volume = "61",
doi = "10.5937/zasmat2003181E"
}

Elezović, N. R., Krstajić-Pajić, M.,& Jović, V. D.. (2020). Sub-monolayers of iridium electrodeposited on Ti2AlC substrate as catalysts for hydrogen evolution reaction in sulfuric acid solution. in Zaštita materijala
Engineering Society for Corrosion, Belgrade, Serbia., 61(3), 181-191.
https://doi.org/10.5937/zasmat2003181E

Elezović NR, Krstajić-Pajić M, Jović VD. Sub-monolayers of iridium electrodeposited on Ti2AlC substrate as catalysts for hydrogen evolution reaction in sulfuric acid solution. in Zaštita materijala. 2020;61(3):181-191.
doi:10.5937/zasmat2003181E .

Elezović, Nevenka R., Krstajić-Pajić, Mila, Jović, Vladimir D., "Sub-monolayers of iridium electrodeposited on Ti2AlC substrate as catalysts for hydrogen evolution reaction in sulfuric acid solution" in Zaštita materijala, 61, no. 3 (2020):181-191,
https://doi.org/10.5937/zasmat2003181E . .

TY  - CONF
AU  - Krstajić Pajić, Mila N.
AU  - Stevanović, Sanja I.
AU  - Radmilović, Vuk V.
AU  - Zabinski, Piotr
AU  - Elezović, Nevenka R.
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7311
AB  - Formic acid is one of the most promising small organic molecules that can be used as fuel in polymer
electrolyte fuel cells. These systems are recognized as high-efficiency energy conversion devices which could
offer energy generated from electrochemical processes. At carbon supported platinum nanoparticles as state
of the art anodic catalysts formic acid oxidation reaction (FAOR) proceeds through a dual path mechanism
that includes the formation of CO in the indirect reaction pathway. Since CO is a catalytic poison, the best
way to address this problem is to synthesize catalysts that would either provide prompt CO oxidation and
removal, or favour the direct reaction pathway to completely avoid CO formation and electrode poisoning.
PtAu systems are considered as efficient catalysts for FAOR due to the ensemble effect of Au on Pt, however
the optimal ratio of these two elements is still quite vague. Given the experience with water in oil
microemulsion synthesis for preparation of shape controlled Pt nanoparticles,1 bimetallic PtAu/C
nanocatalysts were synthesized by the same procedure, following a simultaneous precursor reduction
methodology.2 The amount of the capping agent used, was varied in order to cause formation of
nanoparticles with different shape (cubic or tetrahedron like). Addition of a very low, but very finely dispersed
amount of Au significantly increases the catalytic activity, and also affects kinetic of the particle growth,
influencing the particle shape. Ordered structure of these particles contributes to their stability as well. These
results were obtained by Electrochemical and High Resolution Transmission Electron Microscopy
characterization (HRTEM) with Energy Dispersive X-ray Spectroscopy (EDXS), along with X-Ray Diffraction and
(XRD) and X-Ray Photoelectron Spectroscopy (XPS).
PB  - International Association of Physical Chemists
C3  - Book of Abstracts / 7th Regional Symposium on Electrochemistry – South East Europe & 8th Kurt Schwabe Symposium, Split, Croatia, May 27-30, 2019
T1  - Catalysis at nano level: Promoting Pt nanoparticle activity by Au decoration
SP  - 119
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7311
ER  - 

@conference{
author = "Krstajić Pajić, Mila N. and Stevanović, Sanja I. and Radmilović, Vuk V. and Zabinski, Piotr and Elezović, Nevenka R. and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2019",
abstract = "Formic acid is one of the most promising small organic molecules that can be used as fuel in polymer
electrolyte fuel cells. These systems are recognized as high-efficiency energy conversion devices which could
offer energy generated from electrochemical processes. At carbon supported platinum nanoparticles as state
of the art anodic catalysts formic acid oxidation reaction (FAOR) proceeds through a dual path mechanism
that includes the formation of CO in the indirect reaction pathway. Since CO is a catalytic poison, the best
way to address this problem is to synthesize catalysts that would either provide prompt CO oxidation and
removal, or favour the direct reaction pathway to completely avoid CO formation and electrode poisoning.
PtAu systems are considered as efficient catalysts for FAOR due to the ensemble effect of Au on Pt, however
the optimal ratio of these two elements is still quite vague. Given the experience with water in oil
microemulsion synthesis for preparation of shape controlled Pt nanoparticles,1 bimetallic PtAu/C
nanocatalysts were synthesized by the same procedure, following a simultaneous precursor reduction
methodology.2 The amount of the capping agent used, was varied in order to cause formation of
nanoparticles with different shape (cubic or tetrahedron like). Addition of a very low, but very finely dispersed
amount of Au significantly increases the catalytic activity, and also affects kinetic of the particle growth,
influencing the particle shape. Ordered structure of these particles contributes to their stability as well. These
results were obtained by Electrochemical and High Resolution Transmission Electron Microscopy
characterization (HRTEM) with Energy Dispersive X-ray Spectroscopy (EDXS), along with X-Ray Diffraction and
(XRD) and X-Ray Photoelectron Spectroscopy (XPS).",
publisher = "International Association of Physical Chemists",
journal = "Book of Abstracts / 7th Regional Symposium on Electrochemistry – South East Europe & 8th Kurt Schwabe Symposium, Split, Croatia, May 27-30, 2019",
title = "Catalysis at nano level: Promoting Pt nanoparticle activity by Au decoration",
pages = "119",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7311"
}

Krstajić Pajić, M. N., Stevanović, S. I., Radmilović, V. V., Zabinski, P., Elezović, N. R., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2019). Catalysis at nano level: Promoting Pt nanoparticle activity by Au decoration. in Book of Abstracts / 7th Regional Symposium on Electrochemistry – South East Europe & 8th Kurt Schwabe Symposium, Split, Croatia, May 27-30, 2019
International Association of Physical Chemists., 119.
https://hdl.handle.net/21.15107/rcub_technorep_7311

Krstajić Pajić MN, Stevanović SI, Radmilović VV, Zabinski P, Elezović NR, Radmilović VR, Gojković SL, Jovanović VM. Catalysis at nano level: Promoting Pt nanoparticle activity by Au decoration. in Book of Abstracts / 7th Regional Symposium on Electrochemistry – South East Europe & 8th Kurt Schwabe Symposium, Split, Croatia, May 27-30, 2019. 2019;:119.
https://hdl.handle.net/21.15107/rcub_technorep_7311 .

Krstajić Pajić, Mila N., Stevanović, Sanja I., Radmilović, Vuk V., Zabinski, Piotr, Elezović, Nevenka R., Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Catalysis at nano level: Promoting Pt nanoparticle activity by Au decoration" in Book of Abstracts / 7th Regional Symposium on Electrochemistry – South East Europe & 8th Kurt Schwabe Symposium, Split, Croatia, May 27-30, 2019 (2019):119,
https://hdl.handle.net/21.15107/rcub_technorep_7311 .

TY  - CONF
AU  - Krstajić Pajić, Mila N.
AU  - Stevanović, Sanja I.
AU  - Radmilović, Vuk V.
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7312
AB  - Sve veće potrebe za proizvodnjom energije iz obovljivih izvora, uslovile su intenzivna
istraživanja u pravcu korišćenja ekološki prihvatljivih goriva. Oksidacijom vodonika u
gorivnim spregovima postiže se proizvodnja energije na ekološki prihvatljiv način, a umesto
vodonika mogu se koristiti i mali organski molekuli, poput mravlje kiseline koji su bezbedniji
za upotrebu i transport. Njihova oksidacija u anodnom delu polimer elektrolitnog gorivnog
sprega zahteva upotrebu plemenitih metala kao katalizatora, jer mogu da omoguće njihovu
dehidrogenaciju kao početni stupanj reakcije. Kao do sada najbolji katalizatori za oksidaciju
mravlje kiseline pokazali su se bimetalni PtAu katalizatori, zahvaljujući geometrijskom
efektu zlata na platinu kojim se favorizuje direktni mehanizam oksidacije i izbegava
stvaranje reakcionog intermedijara CO koji se ponaša kao katalitički otrov. U ovom radu
PtAu katalizatori na aktiviranom ugljeniku sintetizovani su mikroemulzionim postupkom, sa
uticajem aditiva kojim je izmenjen oblik čestica, čime je dodatno poboljšana njihova
katalitička sposobnost.
AB  - Ever rising needs for renewable energy, in order to decrease pollution and exploitation of
limited fossil resources, have caused intensive research on the use of eco friendly fuels.
Hydrogen electrooxidation in fuel cells is a promissing process of zero-emission energy
production from a renewable source. Furthermore, using small organic molecules (SOMs)
such as formic acid, instead of hydrogen, makes this process safer and fuel transportation
easier to manage. Oxidation of SOMs in fuel cells requires a noble metal as catalyst, capable
of enabling dehydrogenation of SOM as an initial step of the reaction. Bimetallic PtAu
catalysts are the best catalysts for formic acid oxidation so far, due to the ensemble effect
of Au on Pt which favors the direct oxidation of formic acid, avoiding the formation of CO
that acts as a catalytic poison. In this reseach carbon supported PtAu nanocatalysts were
synthesized by a microemulsion method, in presence of a capping agent that affected the
particle shape, which made further improvement in catalytic performance of these
nanoparticles.
PB  - Beograd : Srpsko hemijsko društvo
C3  - Kratki izvodi radova / 56. savetovanje Srpskog hemijskog društva , Niš 7. i 8. juni 2019
T1  - Bimetalni nanokatalizatori kontrolisanog oblika za anodne reakcije u gorivnim galvanskim spregovima
T1  - Shape controlled bimetallic nanocatalysts for anodic reactions in fuel cells
SP  - 25
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7312
ER  - 

@conference{
author = "Krstajić Pajić, Mila N. and Stevanović, Sanja I. and Radmilović, Vuk V. and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2019",
abstract = "Sve veće potrebe za proizvodnjom energije iz obovljivih izvora, uslovile su intenzivna
istraživanja u pravcu korišćenja ekološki prihvatljivih goriva. Oksidacijom vodonika u
gorivnim spregovima postiže se proizvodnja energije na ekološki prihvatljiv način, a umesto
vodonika mogu se koristiti i mali organski molekuli, poput mravlje kiseline koji su bezbedniji
za upotrebu i transport. Njihova oksidacija u anodnom delu polimer elektrolitnog gorivnog
sprega zahteva upotrebu plemenitih metala kao katalizatora, jer mogu da omoguće njihovu
dehidrogenaciju kao početni stupanj reakcije. Kao do sada najbolji katalizatori za oksidaciju
mravlje kiseline pokazali su se bimetalni PtAu katalizatori, zahvaljujući geometrijskom
efektu zlata na platinu kojim se favorizuje direktni mehanizam oksidacije i izbegava
stvaranje reakcionog intermedijara CO koji se ponaša kao katalitički otrov. U ovom radu
PtAu katalizatori na aktiviranom ugljeniku sintetizovani su mikroemulzionim postupkom, sa
uticajem aditiva kojim je izmenjen oblik čestica, čime je dodatno poboljšana njihova
katalitička sposobnost., Ever rising needs for renewable energy, in order to decrease pollution and exploitation of
limited fossil resources, have caused intensive research on the use of eco friendly fuels.
Hydrogen electrooxidation in fuel cells is a promissing process of zero-emission energy
production from a renewable source. Furthermore, using small organic molecules (SOMs)
such as formic acid, instead of hydrogen, makes this process safer and fuel transportation
easier to manage. Oxidation of SOMs in fuel cells requires a noble metal as catalyst, capable
of enabling dehydrogenation of SOM as an initial step of the reaction. Bimetallic PtAu
catalysts are the best catalysts for formic acid oxidation so far, due to the ensemble effect
of Au on Pt which favors the direct oxidation of formic acid, avoiding the formation of CO
that acts as a catalytic poison. In this reseach carbon supported PtAu nanocatalysts were
synthesized by a microemulsion method, in presence of a capping agent that affected the
particle shape, which made further improvement in catalytic performance of these
nanoparticles.",
publisher = "Beograd : Srpsko hemijsko društvo",
journal = "Kratki izvodi radova / 56. savetovanje Srpskog hemijskog društva , Niš 7. i 8. juni 2019",
title = "Bimetalni nanokatalizatori kontrolisanog oblika za anodne reakcije u gorivnim galvanskim spregovima, Shape controlled bimetallic nanocatalysts for anodic reactions in fuel cells",
pages = "25",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7312"
}

Krstajić Pajić, M. N., Stevanović, S. I., Radmilović, V. V., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2019). Bimetalni nanokatalizatori kontrolisanog oblika za anodne reakcije u gorivnim galvanskim spregovima. in Kratki izvodi radova / 56. savetovanje Srpskog hemijskog društva , Niš 7. i 8. juni 2019
Beograd : Srpsko hemijsko društvo., 25.
https://hdl.handle.net/21.15107/rcub_technorep_7312

Krstajić Pajić MN, Stevanović SI, Radmilović VV, Radmilović VR, Gojković SL, Jovanović VM. Bimetalni nanokatalizatori kontrolisanog oblika za anodne reakcije u gorivnim galvanskim spregovima. in Kratki izvodi radova / 56. savetovanje Srpskog hemijskog društva , Niš 7. i 8. juni 2019. 2019;:25.
https://hdl.handle.net/21.15107/rcub_technorep_7312 .

Krstajić Pajić, Mila N., Stevanović, Sanja I., Radmilović, Vuk V., Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Bimetalni nanokatalizatori kontrolisanog oblika za anodne reakcije u gorivnim galvanskim spregovima" in Kratki izvodi radova / 56. savetovanje Srpskog hemijskog društva , Niš 7. i 8. juni 2019 (2019):25,
https://hdl.handle.net/21.15107/rcub_technorep_7312 .

TY  - THES
AU  - Krstajić-Pajić, Mila
PY  - 2019
UR  - http://eteze.bg.ac.rs/application/showtheses?thesesId=6887
UR  - https://fedorabg.bg.ac.rs/fedora/get/o:20203/bdef:Content/download
UR  - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=51645455
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4679
AB  - Development of novel materials that would enable the commercialization of fuel cell technology and contribute to reduction of fossil fuel usage in energy production is of great importance for the progress of modern society. As a result, the number of scientific papers devoted to this problem is in a significant increase over the past years. When it comes to the oxidation of small organic molecules (SOM) as potential fuel for the fuel cells, in addition to the problem of the high price of platinum used as a catalyst, there is a problem of poisoning the platinum surface by carbon-monoxide formed as an intermediate in the anodic reaction. In this research carbon supported platinum nanoparticles were synthesized by a water-in-oil microemulsion synthesis procedure. The effect of HCl as a capping agent on nanoparticle shape was investigated by adding up to 35 % HCl in the water phase of the microemulsion. The optimal HCl amount was found to be 25%, in which case platinum was synthesized in the form of cubic-shaped nanoparticles. Four prepared catalysts were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD) and (high resolution) transmission electron microscopy (HR)TEM. These analyses confirmed the change in particle shape induced by the capping agent. Metal loading in catalyst powder was determined to be close to 20%, and the particle size calculated from TEM data went from 4 to 8 nm, with the increase of the HCl amount used. The electrochemical characterization and the investigation of these samples in the reactions of formic acid and methanol oxidation revealed improved catalytic performance of the sample that predominantly contained cubic-shaped nanoparticles compared to conventional cube-octahedron shaped particles. The reason of the improved activity and stability of this catalyst lies in the facilitated CO removal from the catalyst surface, and thus improved tolerance to surface poisoning.
AB  - Pronalazak novih materijala koji bi omogućili komercijalizaciju gorivnih spregova i doprineli smanjenju upotrebe fosilnih goriva u proizvodnji energije je od velikog značaja za razvoj savremenog društva. Zbog toga je broj naučnih radova posvećen ovom problemu u značajnom porastu tokom proteklih godina. Kada je u pitanju oksidacija malih organskih molekula kao potencijalnih goriva za gorivni spreg, pored problema visoke cene platine koja se koristi kao katalizator, prisutan je i problem trovanja površine platine ugljen-monoksidom koji se formira kao intermedijar anodne reakcije. U ovom radu nanočestice platine na ugljeničnom nosaču sintetizovane su mikroemulzionim postupkom. Dodatkom različitih količina aditiva HCl tokom sinteze (od 0 do 35 %) ispitan je uticaj dodatka aditiva na oblik nanočestica. Pri optimalnoj koncentraciji od 25% HCl sintetizovane su nanočestice kubnog oblika. Četiri sintetizovana katalizatora okarakterisana su termogravimetrijskom analizom (TGA), rendgenskom difrakcijom X-zraka (XRD), transmisionom elektronskom mikroskopijom (TEM) i transmisionom elektronskom mikroskopijom visoke rezolucije (HRTEM). Ovim metodama potvrđena je promena oblika nanočestica izazvana dodatkom aditiva, utvrđen je udeo metala u katalizatoru (20%) i određena je veličina čestica, koja raste sa porastom udela aditiva (od 4 do 8 nm prema TEM analizi). Elektrohemijskom karakterizacijom i ispitivanjem reakcija oksidacije mravlje kiseline i metanola na ovim katalizatorima, ustanovljeno je da katalizator sa nanočesticama kubnog oblika, i većim udelom preferencijalno orijentisanih ravni (100) pokazuje bolju aktivnost za ove reakcije od katalizatora Pt sa konvencionalnim kub-oktaedarskim česticama. Razlog tome leži u lakšem uklanjanju adsorbovanog CO sa površine nanočestica sa zastupljenim kubnim oblikom.
PB  - Univerzitet u Beogradu, Tehnološko-metalurški fakultet
T1  - Nanostructured platinum based catalysts for electrooxidation of small organic molecules prepared by microemulsion method
T1  - Nanostruktuirani platinski katalizatori za elektrohemijsku oksidaciju malih organskih molekula sintetizovani mikroemulzionim postupkom
UR  - https://hdl.handle.net/21.15107/rcub_technorep_4679
ER  - 

@phdthesis{
author = "Krstajić-Pajić, Mila",
year = "2019",
abstract = "Development of novel materials that would enable the commercialization of fuel cell technology and contribute to reduction of fossil fuel usage in energy production is of great importance for the progress of modern society. As a result, the number of scientific papers devoted to this problem is in a significant increase over the past years. When it comes to the oxidation of small organic molecules (SOM) as potential fuel for the fuel cells, in addition to the problem of the high price of platinum used as a catalyst, there is a problem of poisoning the platinum surface by carbon-monoxide formed as an intermediate in the anodic reaction. In this research carbon supported platinum nanoparticles were synthesized by a water-in-oil microemulsion synthesis procedure. The effect of HCl as a capping agent on nanoparticle shape was investigated by adding up to 35 % HCl in the water phase of the microemulsion. The optimal HCl amount was found to be 25%, in which case platinum was synthesized in the form of cubic-shaped nanoparticles. Four prepared catalysts were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD) and (high resolution) transmission electron microscopy (HR)TEM. These analyses confirmed the change in particle shape induced by the capping agent. Metal loading in catalyst powder was determined to be close to 20%, and the particle size calculated from TEM data went from 4 to 8 nm, with the increase of the HCl amount used. The electrochemical characterization and the investigation of these samples in the reactions of formic acid and methanol oxidation revealed improved catalytic performance of the sample that predominantly contained cubic-shaped nanoparticles compared to conventional cube-octahedron shaped particles. The reason of the improved activity and stability of this catalyst lies in the facilitated CO removal from the catalyst surface, and thus improved tolerance to surface poisoning., Pronalazak novih materijala koji bi omogućili komercijalizaciju gorivnih spregova i doprineli smanjenju upotrebe fosilnih goriva u proizvodnji energije je od velikog značaja za razvoj savremenog društva. Zbog toga je broj naučnih radova posvećen ovom problemu u značajnom porastu tokom proteklih godina. Kada je u pitanju oksidacija malih organskih molekula kao potencijalnih goriva za gorivni spreg, pored problema visoke cene platine koja se koristi kao katalizator, prisutan je i problem trovanja površine platine ugljen-monoksidom koji se formira kao intermedijar anodne reakcije. U ovom radu nanočestice platine na ugljeničnom nosaču sintetizovane su mikroemulzionim postupkom. Dodatkom različitih količina aditiva HCl tokom sinteze (od 0 do 35 %) ispitan je uticaj dodatka aditiva na oblik nanočestica. Pri optimalnoj koncentraciji od 25% HCl sintetizovane su nanočestice kubnog oblika. Četiri sintetizovana katalizatora okarakterisana su termogravimetrijskom analizom (TGA), rendgenskom difrakcijom X-zraka (XRD), transmisionom elektronskom mikroskopijom (TEM) i transmisionom elektronskom mikroskopijom visoke rezolucije (HRTEM). Ovim metodama potvrđena je promena oblika nanočestica izazvana dodatkom aditiva, utvrđen je udeo metala u katalizatoru (20%) i određena je veličina čestica, koja raste sa porastom udela aditiva (od 4 do 8 nm prema TEM analizi). Elektrohemijskom karakterizacijom i ispitivanjem reakcija oksidacije mravlje kiseline i metanola na ovim katalizatorima, ustanovljeno je da katalizator sa nanočesticama kubnog oblika, i većim udelom preferencijalno orijentisanih ravni (100) pokazuje bolju aktivnost za ove reakcije od katalizatora Pt sa konvencionalnim kub-oktaedarskim česticama. Razlog tome leži u lakšem uklanjanju adsorbovanog CO sa površine nanočestica sa zastupljenim kubnim oblikom.",
publisher = "Univerzitet u Beogradu, Tehnološko-metalurški fakultet",
title = "Nanostructured platinum based catalysts for electrooxidation of small organic molecules prepared by microemulsion method, Nanostruktuirani platinski katalizatori za elektrohemijsku oksidaciju malih organskih molekula sintetizovani mikroemulzionim postupkom",
url = "https://hdl.handle.net/21.15107/rcub_technorep_4679"
}

Krstajić-Pajić, M.. (2019). Nanostructured platinum based catalysts for electrooxidation of small organic molecules prepared by microemulsion method. 
Univerzitet u Beogradu, Tehnološko-metalurški fakultet..
https://hdl.handle.net/21.15107/rcub_technorep_4679

Krstajić-Pajić M. Nanostructured platinum based catalysts for electrooxidation of small organic molecules prepared by microemulsion method. 2019;.
https://hdl.handle.net/21.15107/rcub_technorep_4679 .

Krstajić-Pajić, Mila, "Nanostructured platinum based catalysts for electrooxidation of small organic molecules prepared by microemulsion method" (2019),
https://hdl.handle.net/21.15107/rcub_technorep_4679 .

TY  - JOUR
AU  - Krstajić-Pajić, Mila
AU  - Stevanović, Sanja
AU  - Radmilović, Vuk
AU  - Gavrilović-Wohlmuther, Aleksandra
AU  - Zabinski, Piotr
AU  - Elezović, Nevenka R.
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4330
AB  - Low loading PtAu nanoparticles supported on high area carbon were synthesized by water-in-oil microemulsion method and examined for formic acid and methanol oxidation. Prepared catalyst powder was characterized by Xray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). These techniques revealed that the catalyst contains rather agglomerated quasi-spherical particles, similar to 4 nm diameter, composed of a solid solution of Pt and Au with only similar to 4 at% of Au. In spite of such low Au content, both onset and peak potentials for CO oxidation are shifted some 150 mV to more positive values in comparison to Pt synthesized in the same manner due to stronger binding of CO as a result of notable electronic effect. It is important that this small quantity of Au also significantly influences oxidation of formic acid promoting direct path and suppressing indirect path in formic acid oxidation in a degree as expected by a much larger quantity of Au. Such improvement could be due exclusively by ensemble effect of high number of small Pt domains which formation could be possible only by very fine dispersion of such low Au quantity. High number of small Pt domains is corroborated by lower activity for methanol oxidation in comparison to Pt catalyst synthesized by the same procedure. These results emphasize the importance of the Au dispersion on the surface of Pt over its quantity in PtAu catalyst with regards to both, the ensemble and the electronic effects.
PB  - Elsevier Science Bv, Amsterdam
T2  - Applied Catalysis B-Environmental
T1  - Dispersion effect in formic acid oxidation on PtAu/C nanocatalyst prepared by water-in-oil microemulsion method
EP  - 593
SP  - 585
VL  - 243
DO  - 10.1016/j.apcatb.2018.10.064
ER  - 

@article{
author = "Krstajić-Pajić, Mila and Stevanović, Sanja and Radmilović, Vuk and Gavrilović-Wohlmuther, Aleksandra and Zabinski, Piotr and Elezović, Nevenka R. and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2019",
abstract = "Low loading PtAu nanoparticles supported on high area carbon were synthesized by water-in-oil microemulsion method and examined for formic acid and methanol oxidation. Prepared catalyst powder was characterized by Xray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). These techniques revealed that the catalyst contains rather agglomerated quasi-spherical particles, similar to 4 nm diameter, composed of a solid solution of Pt and Au with only similar to 4 at% of Au. In spite of such low Au content, both onset and peak potentials for CO oxidation are shifted some 150 mV to more positive values in comparison to Pt synthesized in the same manner due to stronger binding of CO as a result of notable electronic effect. It is important that this small quantity of Au also significantly influences oxidation of formic acid promoting direct path and suppressing indirect path in formic acid oxidation in a degree as expected by a much larger quantity of Au. Such improvement could be due exclusively by ensemble effect of high number of small Pt domains which formation could be possible only by very fine dispersion of such low Au quantity. High number of small Pt domains is corroborated by lower activity for methanol oxidation in comparison to Pt catalyst synthesized by the same procedure. These results emphasize the importance of the Au dispersion on the surface of Pt over its quantity in PtAu catalyst with regards to both, the ensemble and the electronic effects.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Applied Catalysis B-Environmental",
title = "Dispersion effect in formic acid oxidation on PtAu/C nanocatalyst prepared by water-in-oil microemulsion method",
pages = "593-585",
volume = "243",
doi = "10.1016/j.apcatb.2018.10.064"
}

Krstajić-Pajić, M., Stevanović, S., Radmilović, V., Gavrilović-Wohlmuther, A., Zabinski, P., Elezović, N. R., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2019). Dispersion effect in formic acid oxidation on PtAu/C nanocatalyst prepared by water-in-oil microemulsion method. in Applied Catalysis B-Environmental
Elsevier Science Bv, Amsterdam., 243, 585-593.
https://doi.org/10.1016/j.apcatb.2018.10.064

Krstajić-Pajić M, Stevanović S, Radmilović V, Gavrilović-Wohlmuther A, Zabinski P, Elezović NR, Radmilović VR, Gojković SL, Jovanović VM. Dispersion effect in formic acid oxidation on PtAu/C nanocatalyst prepared by water-in-oil microemulsion method. in Applied Catalysis B-Environmental. 2019;243:585-593.
doi:10.1016/j.apcatb.2018.10.064 .

Krstajić-Pajić, Mila, Stevanović, Sanja, Radmilović, Vuk, Gavrilović-Wohlmuther, Aleksandra, Zabinski, Piotr, Elezović, Nevenka R., Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Dispersion effect in formic acid oxidation on PtAu/C nanocatalyst prepared by water-in-oil microemulsion method" in Applied Catalysis B-Environmental, 243 (2019):585-593,
https://doi.org/10.1016/j.apcatb.2018.10.064 . .

TY  - JOUR
AU  - Krstajić-Pajić, Mila
AU  - Stevanović, Sanja
AU  - Radmilović, Vuk
AU  - Gavrilović-Wohlmuther, Aleksandra
AU  - Rogan, Jelena
AU  - Radmilović, Velimir R.
AU  - Jovanović, Vladislava M.
PY  - 2018
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3832
AB  - PtAu systems are recognized as good catalysts for the oxidation of formic acid electrooxidation, which is investigated as a possible anodic reaction in low-temperature fuel cells. In this research, bimetallic PtAu nanoparticles, supported on high area carbon Vulcan XC-72R, were synthesized by water in oil microemulsion method. The precursor reduction process took place in a single microemulsion, simultaneously, in the presence of 35% of HCl in the water phase, as a capping agent. Electrochemical behavior of the PtAu/C catalyst was investigated at as prepared electrodes by cyclic voltammetry in 0.5M H2SO4 as a supporting electrolyte, and also in the oxidation of adsorbed CO. The results were compared to the Pt/C catalyst prepared by the same synthesis procedure. PtAu/C catalyst powder was also characterized by X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Energy Dispersive X-Ray Spectroscopy (EDS). Average particle diameter, of 2nm, was calculated from XRD data, which is close to the value of 2.82 nm obtained from TEM images. Compared to identically synthesized Pt nanoparticles, the bimetallic ones are significantly smaller. EDS maps of PtAu/C sample confirm the presence of both elements, and indicate a very fine distribution of Au in the sample. Elemental composition of about 20% Au and 80% Pt was also determined from these maps. Prepared catalyst was tested for formic acid electro-oxidation in terms of its activity and stability over the long term cycling. The voltammograms recorded indicate the change of reaction mechanism and better utilization of the catalyst surface in comparison to Pt/C.
AB  - PtAu sistemi se smatraju veoma dobrim katalizatorima za elektrooksidaciju mravlje kiseline, kao moguće anodne reakcije u niskotemperaturnim gorivnim galvanskim spregovima. U ovom radu bimetalne PtAu nanočestice sintetizovane su mikromulzionim postupkom, i u toku sinteze nanete na ugljenični nosač Vulcan XC-72R. Procesi redukcije prekursora odigravaju se simultano, unutar vodene faze iste mikroemulzije, u prisustvu 35% HCl. Elektrohemijske karakteristike katalizatora ispitivane su cikličnom voltametrijomv na 'as prepared' elektrodama u 0.5M H2SO4 kao osnovnom elektrolitu, kao i prilikom oksidacije adsorbovanog CO. Rezultati su upoređeni sa Pt/C katalizatorom sintetizovanim istim postupkom i pod istovetnim uslovima. Pripremljeni PtAu/C prah okarakterisan je takođe difrakcijom X-zraka, transmisionom elektronskom mikroskopijom i energetski disperzionom spektroskoijom. Veličina čestice određena analizom difraktograma X-zraka iznosi 2nm, što je blisko vrednosti dobijenoj analizom TEM snimaka od 2.82 nm. U poređenju sa Pt nanočesticama sintetizovanim na isti način, bimetalne nanočestice su znatno manjeg prečnika. Mape uzorka PtAu/C dobijene energetski disperzionom spektroskopijom potvrđuju prisustvo oba elementa i pokazuju veoma finu distribuciju Au u uzorku. Analizo mapa utvrđeno je i da je katalizator sastava 20% Au i 80% Pt. Konačno, ispitane su aktivnost i stabilnost bimetalnog katalizatora za oksidaciju mravlje kiseline. Snimljeni voltamogrami ukazuju na promenu reakcionog mehanizma i bolje iskorišćenje površine katalizatora u poređenju ra Pt/C katalizatorom sintetizovanim istim postupkom.
PB  - Engineering Society for Corrosion, Belgrade, Serbia
T2  - Zaštita materijala
T1  - PtAu catalyst with enhanced activity for formic acid oxidation
T1  - PtAu katalizator sa poboljšanom aktivnošću za reakciju oksidacije mravlje kiseline
EP  - 166
IS  - 2
SP  - 159
VL  - 59
DO  - 10.5937/ZasMat1802159K
ER  - 

@article{
author = "Krstajić-Pajić, Mila and Stevanović, Sanja and Radmilović, Vuk and Gavrilović-Wohlmuther, Aleksandra and Rogan, Jelena and Radmilović, Velimir R. and Jovanović, Vladislava M.",
year = "2018",
abstract = "PtAu systems are recognized as good catalysts for the oxidation of formic acid electrooxidation, which is investigated as a possible anodic reaction in low-temperature fuel cells. In this research, bimetallic PtAu nanoparticles, supported on high area carbon Vulcan XC-72R, were synthesized by water in oil microemulsion method. The precursor reduction process took place in a single microemulsion, simultaneously, in the presence of 35% of HCl in the water phase, as a capping agent. Electrochemical behavior of the PtAu/C catalyst was investigated at as prepared electrodes by cyclic voltammetry in 0.5M H2SO4 as a supporting electrolyte, and also in the oxidation of adsorbed CO. The results were compared to the Pt/C catalyst prepared by the same synthesis procedure. PtAu/C catalyst powder was also characterized by X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Energy Dispersive X-Ray Spectroscopy (EDS). Average particle diameter, of 2nm, was calculated from XRD data, which is close to the value of 2.82 nm obtained from TEM images. Compared to identically synthesized Pt nanoparticles, the bimetallic ones are significantly smaller. EDS maps of PtAu/C sample confirm the presence of both elements, and indicate a very fine distribution of Au in the sample. Elemental composition of about 20% Au and 80% Pt was also determined from these maps. Prepared catalyst was tested for formic acid electro-oxidation in terms of its activity and stability over the long term cycling. The voltammograms recorded indicate the change of reaction mechanism and better utilization of the catalyst surface in comparison to Pt/C., PtAu sistemi se smatraju veoma dobrim katalizatorima za elektrooksidaciju mravlje kiseline, kao moguće anodne reakcije u niskotemperaturnim gorivnim galvanskim spregovima. U ovom radu bimetalne PtAu nanočestice sintetizovane su mikromulzionim postupkom, i u toku sinteze nanete na ugljenični nosač Vulcan XC-72R. Procesi redukcije prekursora odigravaju se simultano, unutar vodene faze iste mikroemulzije, u prisustvu 35% HCl. Elektrohemijske karakteristike katalizatora ispitivane su cikličnom voltametrijomv na 'as prepared' elektrodama u 0.5M H2SO4 kao osnovnom elektrolitu, kao i prilikom oksidacije adsorbovanog CO. Rezultati su upoređeni sa Pt/C katalizatorom sintetizovanim istim postupkom i pod istovetnim uslovima. Pripremljeni PtAu/C prah okarakterisan je takođe difrakcijom X-zraka, transmisionom elektronskom mikroskopijom i energetski disperzionom spektroskoijom. Veličina čestice određena analizom difraktograma X-zraka iznosi 2nm, što je blisko vrednosti dobijenoj analizom TEM snimaka od 2.82 nm. U poređenju sa Pt nanočesticama sintetizovanim na isti način, bimetalne nanočestice su znatno manjeg prečnika. Mape uzorka PtAu/C dobijene energetski disperzionom spektroskopijom potvrđuju prisustvo oba elementa i pokazuju veoma finu distribuciju Au u uzorku. Analizo mapa utvrđeno je i da je katalizator sastava 20% Au i 80% Pt. Konačno, ispitane su aktivnost i stabilnost bimetalnog katalizatora za oksidaciju mravlje kiseline. Snimljeni voltamogrami ukazuju na promenu reakcionog mehanizma i bolje iskorišćenje površine katalizatora u poređenju ra Pt/C katalizatorom sintetizovanim istim postupkom.",
publisher = "Engineering Society for Corrosion, Belgrade, Serbia",
journal = "Zaštita materijala",
title = "PtAu catalyst with enhanced activity for formic acid oxidation, PtAu katalizator sa poboljšanom aktivnošću za reakciju oksidacije mravlje kiseline",
pages = "166-159",
number = "2",
volume = "59",
doi = "10.5937/ZasMat1802159K"
}

Krstajić-Pajić, M., Stevanović, S., Radmilović, V., Gavrilović-Wohlmuther, A., Rogan, J., Radmilović, V. R.,& Jovanović, V. M.. (2018). PtAu catalyst with enhanced activity for formic acid oxidation. in Zaštita materijala
Engineering Society for Corrosion, Belgrade, Serbia., 59(2), 159-166.
https://doi.org/10.5937/ZasMat1802159K

Krstajić-Pajić M, Stevanović S, Radmilović V, Gavrilović-Wohlmuther A, Rogan J, Radmilović VR, Jovanović VM. PtAu catalyst with enhanced activity for formic acid oxidation. in Zaštita materijala. 2018;59(2):159-166.
doi:10.5937/ZasMat1802159K .

Krstajić-Pajić, Mila, Stevanović, Sanja, Radmilović, Vuk, Gavrilović-Wohlmuther, Aleksandra, Rogan, Jelena, Radmilović, Velimir R., Jovanović, Vladislava M., "PtAu catalyst with enhanced activity for formic acid oxidation" in Zaštita materijala, 59, no. 2 (2018):159-166,
https://doi.org/10.5937/ZasMat1802159K . .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Zabinski, Piotr
AU  - Krstajić-Pajić, Mila
AU  - Tokarski, Tomasz
AU  - Jović, Borka M.
AU  - Jović, Vladimir D.
PY  - 2018
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4011
AB  - The AgPd alloys were electrodeposited onto Au and glassy carbon disc electrodes from the solution containing 0 001 mol dm(-3) PdCl2 + 0.04 mol dm(-3) AgCl + 0.1 mol dm(-3) HCl + 12 mol dm(-3) LiCl under the non-stationary diffusion (quiescent electrolyte) and convective diffusion (omega = 1000 rpm) to the different amounts of charge and at different current densities. Electro-deposited alloy layers were characterized by the anodic linear sweep voltam-metry (ALSV), scanning electron microscopy, energy dispersive X-ray spectro-scopy (EDS) and X-ray photoelectron spectroscopy (XPS). The compositions of the AgPd alloys determined by the EDS were almost identical to the theoretically predicted ones, while the compositions obtained by XPS and ALSV analysis were similar to each other, but different from those obtained by EDS. Deviation from the theoretically predicted values (determined by the ratio j(L)(Pd)/j(Ag)) was more pronounced at lower current densities and lower charges of AgPd alloys electrodeposition, due to the lower current efficiencies for alloys electrodeposition. The ALSV analysis indicated the presence of Ag and Pd, expressed by two ALSV peaks, and in some cases the presence of the additional peak, which was found to correspond to the dissolution of large AgPd crystals, formed at thicker electrodeposits (higher electrodeposition charge), indicating, for the first time, that besides the phase structure, the morphology of alloy electrodeposit could also influence the shape of the ALSV response. In addition to Ag and Pd, the XPS analysis confirmed the presence of AgCl at the surface of samples electrodeposited to low thicknesses (amounts of charge).
PB  - Srpsko hemijsko društvo, Beograd
T2  - Journal of the Serbian Chemical Society
T1  - Electrochemical deposition and characterization of AgPd alloy layers
EP  - 609
IS  - 5
SP  - 593
VL  - 83
DO  - 10.2298/JSC171103011E
ER  - 

@article{
author = "Elezović, Nevenka R. and Zabinski, Piotr and Krstajić-Pajić, Mila and Tokarski, Tomasz and Jović, Borka M. and Jović, Vladimir D.",
year = "2018",
abstract = "The AgPd alloys were electrodeposited onto Au and glassy carbon disc electrodes from the solution containing 0 001 mol dm(-3) PdCl2 + 0.04 mol dm(-3) AgCl + 0.1 mol dm(-3) HCl + 12 mol dm(-3) LiCl under the non-stationary diffusion (quiescent electrolyte) and convective diffusion (omega = 1000 rpm) to the different amounts of charge and at different current densities. Electro-deposited alloy layers were characterized by the anodic linear sweep voltam-metry (ALSV), scanning electron microscopy, energy dispersive X-ray spectro-scopy (EDS) and X-ray photoelectron spectroscopy (XPS). The compositions of the AgPd alloys determined by the EDS were almost identical to the theoretically predicted ones, while the compositions obtained by XPS and ALSV analysis were similar to each other, but different from those obtained by EDS. Deviation from the theoretically predicted values (determined by the ratio j(L)(Pd)/j(Ag)) was more pronounced at lower current densities and lower charges of AgPd alloys electrodeposition, due to the lower current efficiencies for alloys electrodeposition. The ALSV analysis indicated the presence of Ag and Pd, expressed by two ALSV peaks, and in some cases the presence of the additional peak, which was found to correspond to the dissolution of large AgPd crystals, formed at thicker electrodeposits (higher electrodeposition charge), indicating, for the first time, that besides the phase structure, the morphology of alloy electrodeposit could also influence the shape of the ALSV response. In addition to Ag and Pd, the XPS analysis confirmed the presence of AgCl at the surface of samples electrodeposited to low thicknesses (amounts of charge).",
publisher = "Srpsko hemijsko društvo, Beograd",
journal = "Journal of the Serbian Chemical Society",
title = "Electrochemical deposition and characterization of AgPd alloy layers",
pages = "609-593",
number = "5",
volume = "83",
doi = "10.2298/JSC171103011E"
}

Elezović, N. R., Zabinski, P., Krstajić-Pajić, M., Tokarski, T., Jović, B. M.,& Jović, V. D.. (2018). Electrochemical deposition and characterization of AgPd alloy layers. in Journal of the Serbian Chemical Society
Srpsko hemijsko društvo, Beograd., 83(5), 593-609.
https://doi.org/10.2298/JSC171103011E

Elezović NR, Zabinski P, Krstajić-Pajić M, Tokarski T, Jović BM, Jović VD. Electrochemical deposition and characterization of AgPd alloy layers. in Journal of the Serbian Chemical Society. 2018;83(5):593-609.
doi:10.2298/JSC171103011E .

Elezović, Nevenka R., Zabinski, Piotr, Krstajić-Pajić, Mila, Tokarski, Tomasz, Jović, Borka M., Jović, Vladimir D., "Electrochemical deposition and characterization of AgPd alloy layers" in Journal of the Serbian Chemical Society, 83, no. 5 (2018):593-609,
https://doi.org/10.2298/JSC171103011E . .

TY  - JOUR
AU  - Krstajić-Pajić, Mila
AU  - Stevanović, Sanja
AU  - Radmilović, Vuk
AU  - Gavrilović-Wohlmuther, Aleksandra
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2016
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3221
AB  - In this research, a water-in-oil microemulsion method with HCl as a capping agent was applied to synthesize carbon supported Pt catalysts. Varying the concentration of HCl caused changes in the shape of obtained nanoparticles, i.e. preferential growth of certain facets. Addition of catalyst support in the synthesis process facilitated the cleaning procedures necessary to remove the surfactant residues. Prepared catalyst powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD analysis indicated the influence of HCl addition on the crystallite size and crystal habit. TEM revealed that addition of higher amounts of the capping agent led to the formation of a noticable amount of particles with concave cubic or branched-like structures. Influence of the catalyst particles shape on its electrochemical properties was tested in the oxidations of COads, ammonia and formic acid. The latter one was examined in terms of both activity and stability of as prepared and oxide-annealed (electrochemically treated) catalysts. The results clearly demonstrate that even small changes in the nanoparticle surface structure give rise to distinct modifications in their properties. Concave cubic particles, in comparison to other catalysts, show improved catalytic properties and the contribution of their preferentially oriented {100} facets is electrochemically detectable.
PB  - Elsevier Science Bv, Amsterdam
T2  - Applied Catalysis B-Environmental
T1  - Shape evolution of carbon supported Pt nanoparticles: From synthesis to application
EP  - 184
SP  - 174
VL  - 196
DO  - 10.1016/j.apcatb.2016.05.033
ER  - 

@article{
author = "Krstajić-Pajić, Mila and Stevanović, Sanja and Radmilović, Vuk and Gavrilović-Wohlmuther, Aleksandra and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2016",
abstract = "In this research, a water-in-oil microemulsion method with HCl as a capping agent was applied to synthesize carbon supported Pt catalysts. Varying the concentration of HCl caused changes in the shape of obtained nanoparticles, i.e. preferential growth of certain facets. Addition of catalyst support in the synthesis process facilitated the cleaning procedures necessary to remove the surfactant residues. Prepared catalyst powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD analysis indicated the influence of HCl addition on the crystallite size and crystal habit. TEM revealed that addition of higher amounts of the capping agent led to the formation of a noticable amount of particles with concave cubic or branched-like structures. Influence of the catalyst particles shape on its electrochemical properties was tested in the oxidations of COads, ammonia and formic acid. The latter one was examined in terms of both activity and stability of as prepared and oxide-annealed (electrochemically treated) catalysts. The results clearly demonstrate that even small changes in the nanoparticle surface structure give rise to distinct modifications in their properties. Concave cubic particles, in comparison to other catalysts, show improved catalytic properties and the contribution of their preferentially oriented {100} facets is electrochemically detectable.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Applied Catalysis B-Environmental",
title = "Shape evolution of carbon supported Pt nanoparticles: From synthesis to application",
pages = "184-174",
volume = "196",
doi = "10.1016/j.apcatb.2016.05.033"
}

Krstajić-Pajić, M., Stevanović, S., Radmilović, V., Gavrilović-Wohlmuther, A., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2016). Shape evolution of carbon supported Pt nanoparticles: From synthesis to application. in Applied Catalysis B-Environmental
Elsevier Science Bv, Amsterdam., 196, 174-184.
https://doi.org/10.1016/j.apcatb.2016.05.033

Krstajić-Pajić M, Stevanović S, Radmilović V, Gavrilović-Wohlmuther A, Radmilović VR, Gojković SL, Jovanović VM. Shape evolution of carbon supported Pt nanoparticles: From synthesis to application. in Applied Catalysis B-Environmental. 2016;196:174-184.
doi:10.1016/j.apcatb.2016.05.033 .

Krstajić-Pajić, Mila, Stevanović, Sanja, Radmilović, Vuk, Gavrilović-Wohlmuther, Aleksandra, Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Shape evolution of carbon supported Pt nanoparticles: From synthesis to application" in Applied Catalysis B-Environmental, 196 (2016):174-184,
https://doi.org/10.1016/j.apcatb.2016.05.033 . .

TY  - JOUR
AU  - Krstajić-Pajić, Mila
AU  - Stevanović, Sanja
AU  - Radmilović, Vuk
AU  - Rogan, Jelena
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2016
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3321
AB  - Pt nanoparticles supported on Vulcan XC-72R were synthesized by water-in-oil microemulsion method. By incorporating different amounts of HCl as a capping agent in the precursor-containing water phase, nanoparticle shape was varied. Influencing the growth of certain facets leads to the changes of the particle shape depending on the preferential facets. As a result, nanoparticles exhibit some of the electrochemical features typical for single crystals. Commonly employed synthesis procedure for water-in-oil microemulsion method was altered with the addition of catalyst support in the system and changing the catalyst cleaning steps. Prepared catalysts were characterized by thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and electrochemical methods. Activity and stability for methanol oxidation reaction (MOR), a structure-sensitive reaction, were tested. Electrochemical results reveal the influence of particle size, shape and exposed facets on the electrochemical processes. TEM investigations confirm electrochemical findings, while TGA verifies Pt loading in catalyst powder. Based on the results, optimal HCl concentration for cubic particle formation is determined, and structural effect on MOR activity and stability was tested. Cuboidal NPs show very good reaction activity and fair stability under applied experimental conditions.
PB  - Springer, New York
T2  - Journal of Solid State Electrochemistry
T1  - Pt/C nanocatalysts for methanol electrooxidation prepared by water-in-oil microemulsion method
EP  - 3414
IS  - 12
SP  - 3405
VL  - 20
DO  - 10.1007/s10008-016-3319-z
ER  - 

@article{
author = "Krstajić-Pajić, Mila and Stevanović, Sanja and Radmilović, Vuk and Rogan, Jelena and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2016",
abstract = "Pt nanoparticles supported on Vulcan XC-72R were synthesized by water-in-oil microemulsion method. By incorporating different amounts of HCl as a capping agent in the precursor-containing water phase, nanoparticle shape was varied. Influencing the growth of certain facets leads to the changes of the particle shape depending on the preferential facets. As a result, nanoparticles exhibit some of the electrochemical features typical for single crystals. Commonly employed synthesis procedure for water-in-oil microemulsion method was altered with the addition of catalyst support in the system and changing the catalyst cleaning steps. Prepared catalysts were characterized by thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and electrochemical methods. Activity and stability for methanol oxidation reaction (MOR), a structure-sensitive reaction, were tested. Electrochemical results reveal the influence of particle size, shape and exposed facets on the electrochemical processes. TEM investigations confirm electrochemical findings, while TGA verifies Pt loading in catalyst powder. Based on the results, optimal HCl concentration for cubic particle formation is determined, and structural effect on MOR activity and stability was tested. Cuboidal NPs show very good reaction activity and fair stability under applied experimental conditions.",
publisher = "Springer, New York",
journal = "Journal of Solid State Electrochemistry",
title = "Pt/C nanocatalysts for methanol electrooxidation prepared by water-in-oil microemulsion method",
pages = "3414-3405",
number = "12",
volume = "20",
doi = "10.1007/s10008-016-3319-z"
}

Krstajić-Pajić, M., Stevanović, S., Radmilović, V., Rogan, J., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2016). Pt/C nanocatalysts for methanol electrooxidation prepared by water-in-oil microemulsion method. in Journal of Solid State Electrochemistry
Springer, New York., 20(12), 3405-3414.
https://doi.org/10.1007/s10008-016-3319-z

Krstajić-Pajić M, Stevanović S, Radmilović V, Rogan J, Radmilović VR, Gojković SL, Jovanović VM. Pt/C nanocatalysts for methanol electrooxidation prepared by water-in-oil microemulsion method. in Journal of Solid State Electrochemistry. 2016;20(12):3405-3414.
doi:10.1007/s10008-016-3319-z .

Krstajić-Pajić, Mila, Stevanović, Sanja, Radmilović, Vuk, Rogan, Jelena, Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Pt/C nanocatalysts for methanol electrooxidation prepared by water-in-oil microemulsion method" in Journal of Solid State Electrochemistry, 20, no. 12 (2016):3405-3414,
https://doi.org/10.1007/s10008-016-3319-z . .

TY  - CONF
AU  - Krstajić, Mila
AU  - Stevanović, Sanja
AU  - Radmilović, Vuk
AU  - Rogan, Jelena
AU  - Gavrilović-Wohlmuther, Aleksandra
AU  - Radmilović, Velimir R.
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2872
AB  - Electrocatalytic activity of platinum-based electrocatalysts used in fuel cells has been well recognized. However, significant attention remains on the particle shape and size control of such nanomaterials. Catalytic activity can be enhanced by alloying Pt with another element (e.g. Ru and Sn), or by supporting Pt on metal oxides, both of which involve a bifunctional effect. It is also possible to achieve better catalytic characteristics by exposing different Pt crystal facets, which alters chemical and electronic interactions (structural effect). In order to synthesize Pt nanoparticles of a pre-determined shape, water in oil microemulsion method was used, with a few modifications: carbon support (Vulcan XC-72R) was added into the microemulsion itself, just after the completion of the reduction reaction of H2PtCl6 with NaBH4 as the reducing agent and this was crucial for further improvements of the catalyst cleaning procedures. Microemulsion consisted of [n-heptane] / [polyethileneglycoldodecyether (BRIJ30)] / [0,1M H2PtCl6 in 0, 15, 25 and 35% HCl], so four Pt catalyst were formed using different amounts of HCl in the water phase of the microemulsion. In comparison to previously reported applications of the microemulsion method, where electrochemical treatment of catalysts before its application was necessary, this alteration of cleaning steps made use of the “as prepared” catalysts possible. Catalysts A (0% HCl), B (15% HCl), C (25% HCl) and D (35% HCl) were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD) and transmission electron microscopy (TEM), as well as with electrochemical characterization methods (cyclic voltammetry in supporting electrolyte, CO stripping). TEM images confirmed the presence of cubic Pt particles, and indicated their good dispersion on carbon support, while XRD patterns revealed the share of each plane orientation in all investigated catalysts. This acknowledged the influence of HCl in the microemulsion on the shape of Pt particles. Mean particle size was determined both by TEM and XRD investigations, which are in good accordance, and show that average diameters of these four catalysts vary from 3 to 8 nm.
PB  - Academician Evgeni Budevski Institute of Electrochemistry and Energy Systems Bulgarian Academy of Sciences, Sofia, Bulgaria
C3  - 5th Regional Symposium on Electrochemistry South-East Europe, RSE-SEE, Program and Book of Abstracts
T1  - Shape Controlled, Carbon Supported Pt Anodic Catalysts for DFAFC
EP  - 78
SP  - 78
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2872
ER  - 

@conference{
author = "Krstajić, Mila and Stevanović, Sanja and Radmilović, Vuk and Rogan, Jelena and Gavrilović-Wohlmuther, Aleksandra and Radmilović, Velimir R. and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2015",
abstract = "Electrocatalytic activity of platinum-based electrocatalysts used in fuel cells has been well recognized. However, significant attention remains on the particle shape and size control of such nanomaterials. Catalytic activity can be enhanced by alloying Pt with another element (e.g. Ru and Sn), or by supporting Pt on metal oxides, both of which involve a bifunctional effect. It is also possible to achieve better catalytic characteristics by exposing different Pt crystal facets, which alters chemical and electronic interactions (structural effect). In order to synthesize Pt nanoparticles of a pre-determined shape, water in oil microemulsion method was used, with a few modifications: carbon support (Vulcan XC-72R) was added into the microemulsion itself, just after the completion of the reduction reaction of H2PtCl6 with NaBH4 as the reducing agent and this was crucial for further improvements of the catalyst cleaning procedures. Microemulsion consisted of [n-heptane] / [polyethileneglycoldodecyether (BRIJ30)] / [0,1M H2PtCl6 in 0, 15, 25 and 35% HCl], so four Pt catalyst were formed using different amounts of HCl in the water phase of the microemulsion. In comparison to previously reported applications of the microemulsion method, where electrochemical treatment of catalysts before its application was necessary, this alteration of cleaning steps made use of the “as prepared” catalysts possible. Catalysts A (0% HCl), B (15% HCl), C (25% HCl) and D (35% HCl) were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD) and transmission electron microscopy (TEM), as well as with electrochemical characterization methods (cyclic voltammetry in supporting electrolyte, CO stripping). TEM images confirmed the presence of cubic Pt particles, and indicated their good dispersion on carbon support, while XRD patterns revealed the share of each plane orientation in all investigated catalysts. This acknowledged the influence of HCl in the microemulsion on the shape of Pt particles. Mean particle size was determined both by TEM and XRD investigations, which are in good accordance, and show that average diameters of these four catalysts vary from 3 to 8 nm.",
publisher = "Academician Evgeni Budevski Institute of Electrochemistry and Energy Systems Bulgarian Academy of Sciences, Sofia, Bulgaria",
journal = "5th Regional Symposium on Electrochemistry South-East Europe, RSE-SEE, Program and Book of Abstracts",
title = "Shape Controlled, Carbon Supported Pt Anodic Catalysts for DFAFC",
pages = "78-78",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2872"
}

Krstajić, M., Stevanović, S., Radmilović, V., Rogan, J., Gavrilović-Wohlmuther, A., Radmilović, V. R., Gojković, S. Lj.,& Jovanović, V. M.. (2015). Shape Controlled, Carbon Supported Pt Anodic Catalysts for DFAFC. in 5th Regional Symposium on Electrochemistry South-East Europe, RSE-SEE, Program and Book of Abstracts
Academician Evgeni Budevski Institute of Electrochemistry and Energy Systems Bulgarian Academy of Sciences, Sofia, Bulgaria., 78-78.
https://hdl.handle.net/21.15107/rcub_technorep_2872

Krstajić M, Stevanović S, Radmilović V, Rogan J, Gavrilović-Wohlmuther A, Radmilović VR, Gojković SL, Jovanović VM. Shape Controlled, Carbon Supported Pt Anodic Catalysts for DFAFC. in 5th Regional Symposium on Electrochemistry South-East Europe, RSE-SEE, Program and Book of Abstracts. 2015;:78-78.
https://hdl.handle.net/21.15107/rcub_technorep_2872 .

Krstajić, Mila, Stevanović, Sanja, Radmilović, Vuk, Rogan, Jelena, Gavrilović-Wohlmuther, Aleksandra, Radmilović, Velimir R., Gojković, Snežana Lj., Jovanović, Vladislava M., "Shape Controlled, Carbon Supported Pt Anodic Catalysts for DFAFC" in 5th Regional Symposium on Electrochemistry South-East Europe, RSE-SEE, Program and Book of Abstracts (2015):78-78,
https://hdl.handle.net/21.15107/rcub_technorep_2872 .

TY  - JOUR
AU  - Krstajić, Mila
AU  - Stevanović, Sanja
AU  - Rogan, Jelena
AU  - Gojković, Snežana Lj.
AU  - Jovanović, Vladislava M.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2910
AB  - Pt-based nanocatalysts supported on Vulcan XC-72R carbon, were prepared by water-in-oil microemulsion method, with addition of various amounts of HCl in the water phase. Polyethileneglycoldodecylether (BRIJ 30) was used as a surfactant, which influenced the Pt surface structure, along with HCl. Catalysts prepared with addition of 0, 15, 25 and 35 % of HCl during the synthesis, were electrochemically characterised in 0,5 M H2SO4 using cyclic voltammetry and CO oxidation. Formic acid electrooxidation was examined on all investigated catalysts, in terms of their electrocatalytic activity and stability. Platinum loading on carbon support was examined by Thermogravimetric analysis. Catalysts showed different features in hydrogen region, and slight differences in formic acid oxidation mechanisms.
AB  - Platinski nano-katalizatori na ugljeničnom nosaču Vulcan XC-72R sintetizovani su mikroemulzionom metodom, sa različitim sadržajem HCl u vodenoj fazi mikroemulzije. Kao surfaktant korišćen je polietilenglikol-dodeciletar (BRIJ30), čija je uloga da, zajedno sa HCl, utiče na strukturu površine platine. Katalizatori, koji su pripremljeni sa 0, 15, 25 i 35 % HCl u vodenoj fazi, okarakterisani su elektrohemijski u 0,5 M H2SO4, cikličnom voltametrijom i oksidacijom CO. Aktivnost i stabilnost sva četiri katalizatora ispitana je za oksidaciju mravlje kiseline. Udeo platine u prahu pripremljenih katalizatora određen je termogravimetrijskom analizom. Katalizatori su pokazali različito ponašanje u vodoničnoj oblasti osnovnih voltamograma, kao i različitu aktivnost i stabilnost za oksidaciju mravlje kiseline.
PB  - Savez inženjera i tehničara Srbije, Beograd
T2  - Tehnika
T1  - Formic acid electrooxidation on carbon supported platinum catalyst with preferential plane orientation
T1  - Oksidacija mravlje kiseline na platinskim katalizatorima na ugljeničnom nosaču sa preferencijalno orijentisanim ravnima
EP  - 208
IS  - 2
SP  - 203
VL  - 70
DO  - 10.5937/tehnika1502203K
ER  - 

@article{
author = "Krstajić, Mila and Stevanović, Sanja and Rogan, Jelena and Gojković, Snežana Lj. and Jovanović, Vladislava M.",
year = "2015",
abstract = "Pt-based nanocatalysts supported on Vulcan XC-72R carbon, were prepared by water-in-oil microemulsion method, with addition of various amounts of HCl in the water phase. Polyethileneglycoldodecylether (BRIJ 30) was used as a surfactant, which influenced the Pt surface structure, along with HCl. Catalysts prepared with addition of 0, 15, 25 and 35 % of HCl during the synthesis, were electrochemically characterised in 0,5 M H2SO4 using cyclic voltammetry and CO oxidation. Formic acid electrooxidation was examined on all investigated catalysts, in terms of their electrocatalytic activity and stability. Platinum loading on carbon support was examined by Thermogravimetric analysis. Catalysts showed different features in hydrogen region, and slight differences in formic acid oxidation mechanisms., Platinski nano-katalizatori na ugljeničnom nosaču Vulcan XC-72R sintetizovani su mikroemulzionom metodom, sa različitim sadržajem HCl u vodenoj fazi mikroemulzije. Kao surfaktant korišćen je polietilenglikol-dodeciletar (BRIJ30), čija je uloga da, zajedno sa HCl, utiče na strukturu površine platine. Katalizatori, koji su pripremljeni sa 0, 15, 25 i 35 % HCl u vodenoj fazi, okarakterisani su elektrohemijski u 0,5 M H2SO4, cikličnom voltametrijom i oksidacijom CO. Aktivnost i stabilnost sva četiri katalizatora ispitana je za oksidaciju mravlje kiseline. Udeo platine u prahu pripremljenih katalizatora određen je termogravimetrijskom analizom. Katalizatori su pokazali različito ponašanje u vodoničnoj oblasti osnovnih voltamograma, kao i različitu aktivnost i stabilnost za oksidaciju mravlje kiseline.",
publisher = "Savez inženjera i tehničara Srbije, Beograd",
journal = "Tehnika",
title = "Formic acid electrooxidation on carbon supported platinum catalyst with preferential plane orientation, Oksidacija mravlje kiseline na platinskim katalizatorima na ugljeničnom nosaču sa preferencijalno orijentisanim ravnima",
pages = "208-203",
number = "2",
volume = "70",
doi = "10.5937/tehnika1502203K"
}

Krstajić, M., Stevanović, S., Rogan, J., Gojković, S. Lj.,& Jovanović, V. M.. (2015). Formic acid electrooxidation on carbon supported platinum catalyst with preferential plane orientation. in Tehnika
Savez inženjera i tehničara Srbije, Beograd., 70(2), 203-208.
https://doi.org/10.5937/tehnika1502203K

Krstajić M, Stevanović S, Rogan J, Gojković SL, Jovanović VM. Formic acid electrooxidation on carbon supported platinum catalyst with preferential plane orientation. in Tehnika. 2015;70(2):203-208.
doi:10.5937/tehnika1502203K .

Krstajić, Mila, Stevanović, Sanja, Rogan, Jelena, Gojković, Snežana Lj., Jovanović, Vladislava M., "Formic acid electrooxidation on carbon supported platinum catalyst with preferential plane orientation" in Tehnika, 70, no. 2 (2015):203-208,
https://doi.org/10.5937/tehnika1502203K . .

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 .