TY  - JOUR
AU  - Košević, Milica
AU  - Šekularac, Gavrilo
AU  - Živković, Ljiljana S.
AU  - Panić, Vladimir
AU  - Nikolic, Branislav
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5858
AB  - TiO2 powder was synthesized by a forced hydrolysis process and used for the synthesis of Pt/TiO2 composite that is to be foreseen as an advanced electrode material. Pt was incorporated into the synthesized TiO2 from a Pt colloidal dispersion as a precursor prepared by a microwave- assisted polyol process. Physicochemical properties of TiO2 and TiO2- supported Pt were investigated by scanning electron microscopy, dynamic light scattering and X- ray spectroscopy and diffraction techniques. The properties of Pt/TiO2 composite are correlated to the basic voltammetric response of its thin-layer form. It was found that subsequent thermal treatment of synthesized TiO2, which caused crystallization into mainly rutile phase, is required for appropriate Pt incorporation. Although being appropriately loaded by Pt, and the voltammetric response is typical for Pt-based material, the voltammetry of Pt/TiO2 corresponded to much lower loadings.The possibility for Pt particles to be trapped inside TiO2 agglomerates is indicated. The catalyst usage from the synthesized Pt/TiO2 was found quite moderate due to this trapping.
PB  - Croatian Chemical Society
T2  - Croatica Chemica Acta
T1  - TiO2 From Colloidal Dispersion as Support in Pt/TiO2 Nanocomposite for Electrochemical Applications
EP  - 258
IS  - 2
SP  - 251
VL  - 90
DO  - 10.5562/cca3175
ER  - 

@article{
author = "Košević, Milica and Šekularac, Gavrilo and Živković, Ljiljana S. and Panić, Vladimir and Nikolic, Branislav",
year = "2017",
abstract = "TiO2 powder was synthesized by a forced hydrolysis process and used for the synthesis of Pt/TiO2 composite that is to be foreseen as an advanced electrode material. Pt was incorporated into the synthesized TiO2 from a Pt colloidal dispersion as a precursor prepared by a microwave- assisted polyol process. Physicochemical properties of TiO2 and TiO2- supported Pt were investigated by scanning electron microscopy, dynamic light scattering and X- ray spectroscopy and diffraction techniques. The properties of Pt/TiO2 composite are correlated to the basic voltammetric response of its thin-layer form. It was found that subsequent thermal treatment of synthesized TiO2, which caused crystallization into mainly rutile phase, is required for appropriate Pt incorporation. Although being appropriately loaded by Pt, and the voltammetric response is typical for Pt-based material, the voltammetry of Pt/TiO2 corresponded to much lower loadings.The possibility for Pt particles to be trapped inside TiO2 agglomerates is indicated. The catalyst usage from the synthesized Pt/TiO2 was found quite moderate due to this trapping.",
publisher = "Croatian Chemical Society",
journal = "Croatica Chemica Acta",
title = "TiO2 From Colloidal Dispersion as Support in Pt/TiO2 Nanocomposite for Electrochemical Applications",
pages = "258-251",
number = "2",
volume = "90",
doi = "10.5562/cca3175"
}

Košević, M., Šekularac, G., Živković, L. S., Panić, V.,& Nikolic, B.. (2017). TiO2 From Colloidal Dispersion as Support in Pt/TiO2 Nanocomposite for Electrochemical Applications. in Croatica Chemica Acta
Croatian Chemical Society., 90(2), 251-258.
https://doi.org/10.5562/cca3175

Košević M, Šekularac G, Živković LS, Panić V, Nikolic B. TiO2 From Colloidal Dispersion as Support in Pt/TiO2 Nanocomposite for Electrochemical Applications. in Croatica Chemica Acta. 2017;90(2):251-258.
doi:10.5562/cca3175 .

Košević, Milica, Šekularac, Gavrilo, Živković, Ljiljana S., Panić, Vladimir, Nikolic, Branislav, "TiO2 From Colloidal Dispersion as Support in Pt/TiO2 Nanocomposite for Electrochemical Applications" in Croatica Chemica Acta, 90, no. 2 (2017):251-258,
https://doi.org/10.5562/cca3175 . .

TY  - JOUR
AU  - Izrael-Živković, Lidija
AU  - Živković, Ljiljana S.
AU  - Beškoski, Vladimir
AU  - Gopčević, Kristina
AU  - Jokić, Bojan
AU  - Radosavljević, Dragoslav S.
AU  - Karadžić, Ivanka M.
PY  - 2016
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5843
AB  - The immobilization of Candida rugosa lipase by adsorption was performed onto commercial titania powder (Degussa P25). The change of titania particles surface was diagnosed by means of FTIR and FESEM analysis, as well as by shift of zeta potential value towards that of lipase. A detailed study of the effect of immobilization on enzyme kinetic, temperature stability, as well as on potential for its reuse in aqueous organic media was undertaken. Immobilization of lipase altered enzyme affinity toward substrates with different length of carbon chain in hydrolytic reaction. The Vmax value decreased 2–8-fold, where major constraint was registered for the ester containing the longest carbon chain. Thermostability of lipase improved more than 7-fold at 60 °C. Significant potential for reuse in water solutions was also found after immobilization. In cyclohexane immobilized lipase catalyzed synthesis of amyl octanoate by ping-pong bi–bi mechanism with inhibition by amyl alcohol. Obtained kinetic constants were Vmax = 26.4 μmol min−1, KAc = 0.52 mol/L, KAl = 0.2 mol/L and Ki,Al = 0.644 mol/L. Esterification activity remained 60% after 5 reuse cycles in cyclohexane indicating moderate reuse stability. © 2017 Elsevier B.V.
T2  - Journal of Molecular Catalysis. B: Enzymatic
T1  - The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media
VL  - 133
DO  - 10.1016/j.molcatb.2017.06.001
ER  - 

@article{
author = "Izrael-Živković, Lidija and Živković, Ljiljana S. and Beškoski, Vladimir and Gopčević, Kristina and Jokić, Bojan and Radosavljević, Dragoslav S. and Karadžić, Ivanka M.",
year = "2016",
abstract = "The immobilization of Candida rugosa lipase by adsorption was performed onto commercial titania powder (Degussa P25). The change of titania particles surface was diagnosed by means of FTIR and FESEM analysis, as well as by shift of zeta potential value towards that of lipase. A detailed study of the effect of immobilization on enzyme kinetic, temperature stability, as well as on potential for its reuse in aqueous organic media was undertaken. Immobilization of lipase altered enzyme affinity toward substrates with different length of carbon chain in hydrolytic reaction. The Vmax value decreased 2–8-fold, where major constraint was registered for the ester containing the longest carbon chain. Thermostability of lipase improved more than 7-fold at 60 °C. Significant potential for reuse in water solutions was also found after immobilization. In cyclohexane immobilized lipase catalyzed synthesis of amyl octanoate by ping-pong bi–bi mechanism with inhibition by amyl alcohol. Obtained kinetic constants were Vmax = 26.4 μmol min−1, KAc = 0.52 mol/L, KAl = 0.2 mol/L and Ki,Al = 0.644 mol/L. Esterification activity remained 60% after 5 reuse cycles in cyclohexane indicating moderate reuse stability. © 2017 Elsevier B.V.",
journal = "Journal of Molecular Catalysis. B: Enzymatic",
title = "The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media",
volume = "133",
doi = "10.1016/j.molcatb.2017.06.001"
}

Izrael-Živković, L., Živković, L. S., Beškoski, V., Gopčević, K., Jokić, B., Radosavljević, D. S.,& Karadžić, I. M.. (2016). The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media. in Journal of Molecular Catalysis. B: Enzymatic, 133.
https://doi.org/10.1016/j.molcatb.2017.06.001

Izrael-Živković L, Živković LS, Beškoski V, Gopčević K, Jokić B, Radosavljević DS, Karadžić IM. The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media. in Journal of Molecular Catalysis. B: Enzymatic. 2016;133.
doi:10.1016/j.molcatb.2017.06.001 .

Izrael-Živković, Lidija, Živković, Ljiljana S., Beškoski, Vladimir, Gopčević, Kristina, Jokić, Bojan, Radosavljević, Dragoslav S., Karadžić, Ivanka M., "The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media" in Journal of Molecular Catalysis. B: Enzymatic, 133 (2016),
https://doi.org/10.1016/j.molcatb.2017.06.001 . .