Serbian Academy of Sciences and Arts, Project F-141

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Serbian Academy of Sciences and Arts, Project F-141

Authors

Publications

Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag

Nikolić, Irena; Marković, Smilja; Veselinović, Ljiljana; Radmilović, Vuk V.; Janković Častvan, Ivona; Radmilović, Velimir R.

(Elsevier, 2019)

TY  - JOUR
AU  - Nikolić, Irena
AU  - Marković, Smilja
AU  - Veselinović, Ljiljana
AU  - Radmilović, Vuk V.
AU  - Janković Častvan, Ivona
AU  - Radmilović, Velimir R.
PY  - 2019
UR  - http://www.sciencedirect.com/science/article/pii/S0167577X18315908
UR  - https://dais.sanu.ac.rs/123456789/4603
AB  - Pristine electric arc furnace slag (EAFS) as well as EAFS modified by alkali activation i.e. alkali activated slag (AAS) have found a novel application as adsorbents used in Cu2+ removal from sulfate solutions. The adsorption tests were carried in batch conditions and results have shown that alkali activation of EAFS enhances the Cu2+ adsorption. The adsorption process was found to follow a pseudo second-order kinetic model and occurs via formation of posnjakite (Cu4(SO4)(OH)6·H2O) on the surface of both, EAFS and AAS. Enhanced adsorption properties of AAS, compared to EAFS, are attributed to a more porous structure, larger specific surface area and an increased number of surface groups involved in the binding of Cu2+.
PB  - Elsevier
T2  - Materials Letters
T1  - Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag
SP  - 184
EP  - 188
VL  - 235
DO  - 10.1016/j.matlet.2018.10.027
UR  - https://hdl.handle.net/21.15107/rcub_dais_4603
ER  - 
@article{
author = "Nikolić, Irena and Marković, Smilja and Veselinović, Ljiljana and Radmilović, Vuk V. and Janković Častvan, Ivona and Radmilović, Velimir R.",
year = "2019",
abstract = "Pristine electric arc furnace slag (EAFS) as well as EAFS modified by alkali activation i.e. alkali activated slag (AAS) have found a novel application as adsorbents used in Cu2+ removal from sulfate solutions. The adsorption tests were carried in batch conditions and results have shown that alkali activation of EAFS enhances the Cu2+ adsorption. The adsorption process was found to follow a pseudo second-order kinetic model and occurs via formation of posnjakite (Cu4(SO4)(OH)6·H2O) on the surface of both, EAFS and AAS. Enhanced adsorption properties of AAS, compared to EAFS, are attributed to a more porous structure, larger specific surface area and an increased number of surface groups involved in the binding of Cu2+.",
publisher = "Elsevier",
journal = "Materials Letters",
title = "Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag",
pages = "184-188",
volume = "235",
doi = "10.1016/j.matlet.2018.10.027",
url = "https://hdl.handle.net/21.15107/rcub_dais_4603"
}
Nikolić, I., Marković, S., Veselinović, L., Radmilović, V. V., Janković Častvan, I.,& Radmilović, V. R.. (2019). Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag. in Materials Letters
Elsevier., 235, 184-188.
https://doi.org/10.1016/j.matlet.2018.10.027
https://hdl.handle.net/21.15107/rcub_dais_4603
Nikolić I, Marković S, Veselinović L, Radmilović VV, Janković Častvan I, Radmilović VR. Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag. in Materials Letters. 2019;235:184-188.
doi:10.1016/j.matlet.2018.10.027
https://hdl.handle.net/21.15107/rcub_dais_4603 .
Nikolić, Irena, Marković, Smilja, Veselinović, Ljiljana, Radmilović, Vuk V., Janković Častvan, Ivona, Radmilović, Velimir R., "Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag" in Materials Letters, 235 (2019):184-188,
https://doi.org/10.1016/j.matlet.2018.10.027 .,
https://hdl.handle.net/21.15107/rcub_dais_4603 .
1
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Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag

Nikolić, Irena; Marković, Smilja; Veselinović, Ljiljana; Radmilović, Vuk V.; Janković Častvan, Ivona; Radmilović, Velimir R.

(Elsevier, 2019)

TY  - JOUR
AU  - Nikolić, Irena
AU  - Marković, Smilja
AU  - Veselinović, Ljiljana
AU  - Radmilović, Vuk V.
AU  - Janković Častvan, Ivona
AU  - Radmilović, Velimir R.
PY  - 2019
UR  - http://www.sciencedirect.com/science/article/pii/S0167577X18315908
UR  - https://dais.sanu.ac.rs/123456789/4551
AB  - Pristine electric arc furnace slag (EAFS) as well as EAFS modified by alkali activation i.e. alkali activated slag (AAS) have found a novel application as adsorbents used in Cu2+ removal from sulfate solutions. The adsorption tests were carried in batch conditions and results have shown that alkali activation of EAFS enhances the Cu2+ adsorption. The adsorption process was found to follow a pseudo second-order kinetic model and occurs via formation of posnjakite (Cu4(SO4)(OH)6·H2O) on the surface of both, EAFS and AAS. Enhanced adsorption properties of AAS, compared to EAFS, are attributed to a more porous structure, larger specific surface area and an increased number of surface groups involved in the binding of Cu2+.
PB  - Elsevier
T2  - Materials Letters
T1  - Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag
SP  - 184
EP  - 188
VL  - 235
DO  - 10.1016/j.matlet.2018.10.027
UR  - https://hdl.handle.net/21.15107/rcub_dais_4551
ER  - 
@article{
author = "Nikolić, Irena and Marković, Smilja and Veselinović, Ljiljana and Radmilović, Vuk V. and Janković Častvan, Ivona and Radmilović, Velimir R.",
year = "2019",
abstract = "Pristine electric arc furnace slag (EAFS) as well as EAFS modified by alkali activation i.e. alkali activated slag (AAS) have found a novel application as adsorbents used in Cu2+ removal from sulfate solutions. The adsorption tests were carried in batch conditions and results have shown that alkali activation of EAFS enhances the Cu2+ adsorption. The adsorption process was found to follow a pseudo second-order kinetic model and occurs via formation of posnjakite (Cu4(SO4)(OH)6·H2O) on the surface of both, EAFS and AAS. Enhanced adsorption properties of AAS, compared to EAFS, are attributed to a more porous structure, larger specific surface area and an increased number of surface groups involved in the binding of Cu2+.",
publisher = "Elsevier",
journal = "Materials Letters",
title = "Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag",
pages = "184-188",
volume = "235",
doi = "10.1016/j.matlet.2018.10.027",
url = "https://hdl.handle.net/21.15107/rcub_dais_4551"
}
Nikolić, I., Marković, S., Veselinović, L., Radmilović, V. V., Janković Častvan, I.,& Radmilović, V. R.. (2019). Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag. in Materials Letters
Elsevier., 235, 184-188.
https://doi.org/10.1016/j.matlet.2018.10.027
https://hdl.handle.net/21.15107/rcub_dais_4551
Nikolić I, Marković S, Veselinović L, Radmilović VV, Janković Častvan I, Radmilović VR. Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag. in Materials Letters. 2019;235:184-188.
doi:10.1016/j.matlet.2018.10.027
https://hdl.handle.net/21.15107/rcub_dais_4551 .
Nikolić, Irena, Marković, Smilja, Veselinović, Ljiljana, Radmilović, Vuk V., Janković Častvan, Ivona, Radmilović, Velimir R., "Enhanced sorption of Cu2+ from sulfate solutions onto modified electric arc furnace slag" in Materials Letters, 235 (2019):184-188,
https://doi.org/10.1016/j.matlet.2018.10.027 .,
https://hdl.handle.net/21.15107/rcub_dais_4551 .
1
1
2

Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag

Nikolić, Irena; Marković, Smilja; Janković Častvan, Ivona; Radmilović, Vuk V.; Karanović, Ljiljana; Babić, Biljana M.; Radmilović, Velimir R.

(Elsevier, 2016)

TY  - JOUR
AU  - Nikolić, Irena
AU  - Marković, Smilja
AU  - Janković Častvan, Ivona
AU  - Radmilović, Vuk V.
AU  - Karanović, Ljiljana
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
PY  - 2016
UR  - https://dais.sanu.ac.rs/123456789/4639
AB  - Geopolymeric binders (GB) were produced using fly ash (FA) and electric arc furnace slag (EAFS). The slag has been added in the range of 0–40%. The effects of slag content on the strength, microstructure and thermal resistance were evaluated. It was found that the amount of EAFS up to 30% positively affects the strength evolution of GB. The main reaction product of FA/EAFS blends was amorphous N–(C)–A–S–H gel along with geopolymer-type gel (N–A–S–H). Thermal resistance of GB was considered from the standpoint of their mechanical and dimensional stability after heating in the temperature interval of 600–800 °C. The changes in mechanical and thermal properties of GB after heating are attributed to the changes in their structure. The results have shown that EAFS negatively affects the thermal resistance of GB above 600 °C due to the phase transition and morphological transformation of the amorphous gel phase.
PB  - Elsevier
T2  - Materials Letters
T1  - Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag
SP  - 301
EP  - 305
VL  - 176
DO  - 10.1016/j.matlet.2016.04.121
UR  - https://hdl.handle.net/21.15107/rcub_dais_4639
ER  - 
@article{
author = "Nikolić, Irena and Marković, Smilja and Janković Častvan, Ivona and Radmilović, Vuk V. and Karanović, Ljiljana and Babić, Biljana M. and Radmilović, Velimir R.",
year = "2016",
abstract = "Geopolymeric binders (GB) were produced using fly ash (FA) and electric arc furnace slag (EAFS). The slag has been added in the range of 0–40%. The effects of slag content on the strength, microstructure and thermal resistance were evaluated. It was found that the amount of EAFS up to 30% positively affects the strength evolution of GB. The main reaction product of FA/EAFS blends was amorphous N–(C)–A–S–H gel along with geopolymer-type gel (N–A–S–H). Thermal resistance of GB was considered from the standpoint of their mechanical and dimensional stability after heating in the temperature interval of 600–800 °C. The changes in mechanical and thermal properties of GB after heating are attributed to the changes in their structure. The results have shown that EAFS negatively affects the thermal resistance of GB above 600 °C due to the phase transition and morphological transformation of the amorphous gel phase.",
publisher = "Elsevier",
journal = "Materials Letters",
title = "Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag",
pages = "301-305",
volume = "176",
doi = "10.1016/j.matlet.2016.04.121",
url = "https://hdl.handle.net/21.15107/rcub_dais_4639"
}
Nikolić, I., Marković, S., Janković Častvan, I., Radmilović, V. V., Karanović, L., Babić, B. M.,& Radmilović, V. R.. (2016). Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag. in Materials Letters
Elsevier., 176, 301-305.
https://doi.org/10.1016/j.matlet.2016.04.121
https://hdl.handle.net/21.15107/rcub_dais_4639
Nikolić I, Marković S, Janković Častvan I, Radmilović VV, Karanović L, Babić BM, Radmilović VR. Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag. in Materials Letters. 2016;176:301-305.
doi:10.1016/j.matlet.2016.04.121
https://hdl.handle.net/21.15107/rcub_dais_4639 .
Nikolić, Irena, Marković, Smilja, Janković Častvan, Ivona, Radmilović, Vuk V., Karanović, Ljiljana, Babić, Biljana M., Radmilović, Velimir R., "Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag" in Materials Letters, 176 (2016):301-305,
https://doi.org/10.1016/j.matlet.2016.04.121 .,
https://hdl.handle.net/21.15107/rcub_dais_4639 .
54
26
53

Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag

Nikolić, Irena; Marković, Smilja; Janković Častvan, Ivona; Radmilović, Vuk V.; Karanović, Ljiljana; Babić, Biljana M.; Radmilović, Velimir R.

(Elsevier, 2016)

TY  - JOUR
AU  - Nikolić, Irena
AU  - Marković, Smilja
AU  - Janković Častvan, Ivona
AU  - Radmilović, Vuk V.
AU  - Karanović, Ljiljana
AU  - Babić, Biljana M.
AU  - Radmilović, Velimir R.
PY  - 2016
UR  - https://dais.sanu.ac.rs/123456789/15992
AB  - Geopolymeric binders (GB) were produced using fly ash (FA) and electric arc furnace slag (EAFS). The slag has been added in the range of 0–40%. The effects of slag content on the strength, microstructure and thermal resistance were evaluated. It was found that the amount of EAFS up to 30% positively affects the strength evolution of GB. The main reaction product of FA/EAFS blends was amorphous N–(C)–A–S–H gel along with geopolymer-type gel (N–A–S–H). Thermal resistance of GB was considered from the standpoint of their mechanical and dimensional stability after heating in the temperature interval of 600–800 °C. The changes in mechanical and thermal properties of GB after heating are attributed to the changes in their structure. The results have shown that EAFS negatively affects the thermal resistance of GB above 600 °C due to the phase transition and morphological transformation of the amorphous gel phase.
PB  - Elsevier
T2  - Materials Letters
T1  - Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag
SP  - 301
EP  - 305
VL  - 176
DO  - 10.1016/j.matlet.2016.04.121
UR  - https://hdl.handle.net/21.15107/rcub_dais_15992
ER  - 
@article{
author = "Nikolić, Irena and Marković, Smilja and Janković Častvan, Ivona and Radmilović, Vuk V. and Karanović, Ljiljana and Babić, Biljana M. and Radmilović, Velimir R.",
year = "2016",
abstract = "Geopolymeric binders (GB) were produced using fly ash (FA) and electric arc furnace slag (EAFS). The slag has been added in the range of 0–40%. The effects of slag content on the strength, microstructure and thermal resistance were evaluated. It was found that the amount of EAFS up to 30% positively affects the strength evolution of GB. The main reaction product of FA/EAFS blends was amorphous N–(C)–A–S–H gel along with geopolymer-type gel (N–A–S–H). Thermal resistance of GB was considered from the standpoint of their mechanical and dimensional stability after heating in the temperature interval of 600–800 °C. The changes in mechanical and thermal properties of GB after heating are attributed to the changes in their structure. The results have shown that EAFS negatively affects the thermal resistance of GB above 600 °C due to the phase transition and morphological transformation of the amorphous gel phase.",
publisher = "Elsevier",
journal = "Materials Letters",
title = "Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag",
pages = "301-305",
volume = "176",
doi = "10.1016/j.matlet.2016.04.121",
url = "https://hdl.handle.net/21.15107/rcub_dais_15992"
}
Nikolić, I., Marković, S., Janković Častvan, I., Radmilović, V. V., Karanović, L., Babić, B. M.,& Radmilović, V. R.. (2016). Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag. in Materials Letters
Elsevier., 176, 301-305.
https://doi.org/10.1016/j.matlet.2016.04.121
https://hdl.handle.net/21.15107/rcub_dais_15992
Nikolić I, Marković S, Janković Častvan I, Radmilović VV, Karanović L, Babić BM, Radmilović VR. Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag. in Materials Letters. 2016;176:301-305.
doi:10.1016/j.matlet.2016.04.121
https://hdl.handle.net/21.15107/rcub_dais_15992 .
Nikolić, Irena, Marković, Smilja, Janković Častvan, Ivona, Radmilović, Vuk V., Karanović, Ljiljana, Babić, Biljana M., Radmilović, Velimir R., "Modification of mechanical and thermal properties of fly ash-based geopolymer by the incorporation of steel slag" in Materials Letters, 176 (2016):301-305,
https://doi.org/10.1016/j.matlet.2016.04.121 .,
https://hdl.handle.net/21.15107/rcub_dais_15992 .
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53

Pt nanoparticles on tin oxide based support as a beneficial catalyst for oxygen reduction in alkaline solutions

Elezović, Nevenka; Radmilović, Velimir R.; Kovač, Janez; Babić, Biljana M.; Gajić Krstajić, Ljiljana; Krstajić, Nedeljko

(2015)

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 .
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