TY  - JOUR
AU  - Elezović, Nevenka
AU  - Radmilović, Velimir R.
AU  - Kovač, Janez
AU  - Babić, Biljana M.
AU  - Gajić Krstajić, Ljiljana
AU  - Krstajić, Nedeljko
PY  - 2015
UR  - https://dais.sanu.ac.rs/123456789/3354
AB  - A platinum nanocatalyst on Sb doped tin oxide support (Sb-SnO2) was synthesized and characterized as a catalyst for oxygen reduction reaction in 0.1 mol dm(-3) NaOH solution at 25 degrees C. Sb (5%) doped tin oxide support was synthesized by a modified hydrazine reduction procedure. The platinum nanocatalyst (20% Pt) on Sb-SnO2 support was synthesized by a borohydride reduction method. The synthesized support and catalyst were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) and X-ray diffraction technique (XRD). X-ray photoelectron spectroscopy was applied to characterize the chemical status of elements before and after Pt-treatment. XPS spectra of Sn 3d, Pt 4f, Sb 3d and O 1s revealed that the Pt-deposition on Sb-SnO2 support induced the reduction of the Sn(4+) oxidation state to Sn(2+) and Sn(0) states, while Pt remained in the metallic state and Sb was in the (3+) oxidation state. Homogenous Pt nanoparticle distribution over the support, without pronounced particle agglomeration, was confirmed by HRTEM technique. The average Pt particle size was 2.9 nm. The electrochemically active Pt surface area of the catalyst was determined by the integration of the cyclic voltammetry curve in the potential region of underpotential deposition of hydrogen, after double layer charge correction, taking into account the reference value of 210 mu C cm(-2) for full monolayer coverage. This calculation gave the value of 51 m(2) g(-1). The kinetics of the oxygen reduction reaction with Pt/[Sb-SnO2 catalyst was studied by cyclic voltammetry and linear sweep voltammetry using a rotating gold disc electrode. Two different Tafel slopes were observed: one close to 60 mV dec(-1) in the low current density region, and another at similar to 120 mV dec(-1) in the higher current densities region, as was already referred in previous reports for the oxygen reduction reaction with polycrystalline Pt, as well as with different Pt based nanocatalysts. The specific activities for oxygen reduction, expressed in terms of kinetic current densities per electrochemically Pt active surface area, as well as per mass of Pt loaded, at the constant potential of practical interest (0.85 V and 0.90 V vs. RHE), were compared to a carbon supported (Vulcan XC-72) catalyst. The Pt/[Sb-SnO2 catalyst exhibited similar catalytic activity for oxygen reduction reaction like carbon supported one. The advantages of the carbon free support application in terms of the durability and stability of the catalysts were proved by accelerated stability tests.
T2  - RSC Advances
T1  - Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions
SP  - 15923
EP  - 15929
VL  - 5
IS  - 21
DO  - 10.1039/c4ra13391a
UR  - https://hdl.handle.net/21.15107/rcub_dais_3354
ER  - 

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

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

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

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

TY  - JOUR
AU  - Rafailović, Lidija D.
AU  - Gammer, Christoph
AU  - Rentenberger, C.
AU  - Trišović, Tomislav
AU  - Kleber, Christoph
AU  - Karnthaler, Hans-Peter
PY  - 2015
UR  - https://dais.sanu.ac.rs/123456789/3516
AB  - A novel synthesis strategy is presented for depositing metallic Ag at the anode during simultaneous electrochemical oxidation of Al. This unexpected result is achieved based on galvanic coupling. Metallic dendritic nanostructures well-anchored in a high surface area supporting matrix are envisioned to open up a new avenue of applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PB  - Weinheim : WILEY‐VCH Verlag
T2  - Advanced Materials
T1  - Functionalizing Aluminum Oxide by Ag Dendrite Deposition at the Anode during Simultaneous Electrochemical Oxidation of Al
SP  - 6438
EP  - 6443
VL  - 27
IS  - 41
DO  - 10.1002/adma.201502451
UR  - https://hdl.handle.net/21.15107/rcub_dais_3516
ER  - 

@article{
author = "Rafailović, Lidija D. and Gammer, Christoph and Rentenberger, C. and Trišović, Tomislav and Kleber, Christoph and Karnthaler, Hans-Peter",
year = "2015",
abstract = "A novel synthesis strategy is presented for depositing metallic Ag at the anode during simultaneous electrochemical oxidation of Al. This unexpected result is achieved based on galvanic coupling. Metallic dendritic nanostructures well-anchored in a high surface area supporting matrix are envisioned to open up a new avenue of applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.",
publisher = "Weinheim : WILEY‐VCH Verlag",
journal = "Advanced Materials",
title = "Functionalizing Aluminum Oxide by Ag Dendrite Deposition at the Anode during Simultaneous Electrochemical Oxidation of Al",
pages = "6438-6443",
volume = "27",
number = "41",
doi = "10.1002/adma.201502451",
url = "https://hdl.handle.net/21.15107/rcub_dais_3516"
}

Rafailović, L. D., Gammer, C., Rentenberger, C., Trišović, T., Kleber, C.,& Karnthaler, H.. (2015). Functionalizing Aluminum Oxide by Ag Dendrite Deposition at the Anode during Simultaneous Electrochemical Oxidation of Al. in Advanced Materials
Weinheim : WILEY‐VCH Verlag., 27(41), 6438-6443.
https://doi.org/10.1002/adma.201502451
https://hdl.handle.net/21.15107/rcub_dais_3516

Rafailović LD, Gammer C, Rentenberger C, Trišović T, Kleber C, Karnthaler H. Functionalizing Aluminum Oxide by Ag Dendrite Deposition at the Anode during Simultaneous Electrochemical Oxidation of Al. in Advanced Materials. 2015;27(41):6438-6443.
doi:10.1002/adma.201502451
https://hdl.handle.net/21.15107/rcub_dais_3516 .

Rafailović, Lidija D., Gammer, Christoph, Rentenberger, C., Trišović, Tomislav, Kleber, Christoph, Karnthaler, Hans-Peter, "Functionalizing Aluminum Oxide by Ag Dendrite Deposition at the Anode during Simultaneous Electrochemical Oxidation of Al" in Advanced Materials, 27, no. 41 (2015):6438-6443,
https://doi.org/10.1002/adma.201502451 .,
https://hdl.handle.net/21.15107/rcub_dais_3516 .

TY  - JOUR
AU  - Elezović, Nevenka R.
AU  - Babić, Biljana M.
AU  - Gajić Krstajić, Ljiljana
AU  - Radmilović, Velimir R.
AU  - Krstajić, Nedeljko
AU  - Vračar, Ljiljana
PY  - 2010
UR  - https://dais.sanu.ac.rs/123456789/3418
AB  - In order to point out the effect of the support to the catalyst for oxygen reduction reaction nano-crystalline Nb-doped TiO2 was synthesized through a modified sol-gel route procedure. The specific surface area of the support, SBET, and pore size distribution, were calculated from the adsorption isotherms using the gravimetric McBain method. The support was characterized by X-ray diffraction (XRD) technique. The borohydride reduction method was used to prepare Nb-TiO2 supported Pt (20 wt.%) catalyst. The synthesized catalyst was analyzed by TEM technique. Finally, the catalytic activity of this new catalyst for oxygen reduction reaction was investigated in acid solution, in the absence and the presence of methanol, and its activity was compared towards the results on C/Pt catalysts. Kinetic analysis reveals that the oxygen reduction reaction on Nb-TiO2/Pt catalyst follows four-electron process leading to water, as in the case of C/Pt electrode, but the Tafel plots normalized to the electrochemically active surface area show very remarkable enhancement in activity of Nb-TiO2/Pt expressed through the value of the current density at the constant potential. Moreover, Nb-TiO2/Pt catalyst exhibits higher methanol tolerance during the oxygen reduction reaction than the C/Pt catalyst. The enhancement in the activity of Nb-TiO2/Pt is consequence of both: the interactions of Pt nanoparticles with the support and the energy shift of the surface d-states with respect to the Fermi level what changes the surface reactivity. © 2010 Elsevier B.V.
PB  - Elsevier
T2  - Journal of Power Sources
T1  - Synthesis, characterization and electrocatalytical behavior of Nb-TiO2/Pt nanocatalyst for oxygen reduction reaction
SP  - 3961
EP  - 3968
VL  - 195
IS  - 13
DO  - 10.1016/j.jpowsour.2010.01.035
UR  - https://hdl.handle.net/21.15107/rcub_dais_3418
ER  - 

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

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

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

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

TY  - JOUR
AU  - Stojanović, D.
AU  - Orlović, A.
AU  - Glišić, S. B.
AU  - Marković, Smilja
AU  - Radmilović, Velimir R.
AU  - Uskoković, Petar S.
AU  - Aleksić, Radoslav
PY  - 2010
UR  - https://dais.sanu.ac.rs/123456789/3427
AB  - The objective of this study is to investigate and compare methods of nanosilica coating with γ-methacryloxypropyltrimethoxy (MEMO) silane using supercritical carbon dioxide and carbon dioxide-ethanol mixture. Characterization of grafted silane coupling agent on the nanosilica surface was performed by the infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The d50 value and particle size distribution were determined by laser particle size analyzer (PSA). The operating parameters of silanization process at 40 °C, such as the silica/silane weight ratio, the presence of ethanol, and the pressure, were found to be important for the successful coating of silica particles with minimum agglomeration. The results indicate that presence of ethanol in high-pressure carbon dioxide plays an important role in achieving successful deagglomeration of coated nanoparticles. Dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) revealed that dispersion of the silica particles in the PMMA matrix and interfacial adhesion between silica particles and polymer matrix were enhanced, when silica nanoparticles treated with silane under high pressure of carbon dioxide and ethanol were used for the nanocomposite preparation. © 2010 Elsevier B.V. All rights reserved.
PB  - Elsevier
T2  - Journal of Supercritical Fluids
T1  - Preparation of MEMO silane-coated SiO2 nanoparticles under high pressure of carbon dioxide and ethanol
SP  - 276
EP  - 284
VL  - 52
IS  - 3
DO  - 10.1016/j.supflu.2010.02.004
UR  - https://hdl.handle.net/21.15107/rcub_dais_3427
ER  - 

@article{
author = "Stojanović, D. and Orlović, A. and Glišić, S. B. and Marković, Smilja and Radmilović, Velimir R. and Uskoković, Petar S. and Aleksić, Radoslav",
year = "2010",
abstract = "The objective of this study is to investigate and compare methods of nanosilica coating with γ-methacryloxypropyltrimethoxy (MEMO) silane using supercritical carbon dioxide and carbon dioxide-ethanol mixture. Characterization of grafted silane coupling agent on the nanosilica surface was performed by the infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The d50 value and particle size distribution were determined by laser particle size analyzer (PSA). The operating parameters of silanization process at 40 °C, such as the silica/silane weight ratio, the presence of ethanol, and the pressure, were found to be important for the successful coating of silica particles with minimum agglomeration. The results indicate that presence of ethanol in high-pressure carbon dioxide plays an important role in achieving successful deagglomeration of coated nanoparticles. Dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) revealed that dispersion of the silica particles in the PMMA matrix and interfacial adhesion between silica particles and polymer matrix were enhanced, when silica nanoparticles treated with silane under high pressure of carbon dioxide and ethanol were used for the nanocomposite preparation. © 2010 Elsevier B.V. All rights reserved.",
publisher = "Elsevier",
journal = "Journal of Supercritical Fluids",
title = "Preparation of MEMO silane-coated SiO2 nanoparticles under high pressure of carbon dioxide and ethanol",
pages = "276-284",
volume = "52",
number = "3",
doi = "10.1016/j.supflu.2010.02.004",
url = "https://hdl.handle.net/21.15107/rcub_dais_3427"
}

Stojanović, D., Orlović, A., Glišić, S. B., Marković, S., Radmilović, V. R., Uskoković, P. S.,& Aleksić, R.. (2010). Preparation of MEMO silane-coated SiO2 nanoparticles under high pressure of carbon dioxide and ethanol. in Journal of Supercritical Fluids
Elsevier., 52(3), 276-284.
https://doi.org/10.1016/j.supflu.2010.02.004
https://hdl.handle.net/21.15107/rcub_dais_3427

Stojanović D, Orlović A, Glišić SB, Marković S, Radmilović VR, Uskoković PS, Aleksić R. Preparation of MEMO silane-coated SiO2 nanoparticles under high pressure of carbon dioxide and ethanol. in Journal of Supercritical Fluids. 2010;52(3):276-284.
doi:10.1016/j.supflu.2010.02.004
https://hdl.handle.net/21.15107/rcub_dais_3427 .

Stojanović, D., Orlović, A., Glišić, S. B., Marković, Smilja, Radmilović, Velimir R., Uskoković, Petar S., Aleksić, Radoslav, "Preparation of MEMO silane-coated SiO2 nanoparticles under high pressure of carbon dioxide and ethanol" in Journal of Supercritical Fluids, 52, no. 3 (2010):276-284,
https://doi.org/10.1016/j.supflu.2010.02.004 .,
https://hdl.handle.net/21.15107/rcub_dais_3427 .