TY  - JOUR
AU  - Božilović, Bojana
AU  - Nikolić, Bogdan
AU  - Waisi, Hadi
AU  - Trifković, Jelena
AU  - Dodevski, Vladimir
AU  - Janković, Bojan
AU  - Krstić, Sanja
AU  - Mojović, Miloš
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11876
AB  - Brassinosteroids (BRs) are a class of plant hormones that play important roles in regulating various physiological and developmental processes in plants. One of the most effective BRs involved in modulating crop growth is 24-epibrassinolide (24-EBL). The effects of different concentrations of 24-EBL on various biochemical and biophysical parameters critical to early growth stages and seedling development were investigated using two maize hybrids, ‘ZP 434’ (a new-generation hybrid) and ‘ZP 704’ (an older-generation hybrid). The evaluation of results is based on measurements of germination percentage, morphometric parameters, redox status, comparative analysis of thermodynamic parameters (such as Gibbs free energy, enthalpy, entropy), and the concentration of specific sugars in different parts of maize seedlings. The results indicate that the germination and initial growth of maize seedlings are influenced by the flow of crucial sugars from the remaining seed (as a source of nutrients) towards the plumule and radicle (as sink organs). Furthermore, alterations in Gibbs free energy play a significant role in these sugar transfers within the maize seedlings. The seed germination was most affected by the highest concentrations of 24-EBL, showing inhibitory effects, whereas lower and moderate concentrations of exogenously added 24-EBL exhibited a beneficial influence on the initial phases of seedling growth. The mentioned approach gives new insights into source–sink relationships and can be used as a quantitative measure of the germination energy, which until now has been a qualitative criterion in seed science.
T2  - Agronomy
T1  - Influence of 24-Epibrassinolide on the Energetic Parameters and Early Stages of Growth and Development in Seedlings of Two Maize (Zea mays L.) Genotypes
VL  - 13
IS  - 7
SP  - 1673
DO  - 10.3390/agronomy13071673
ER  - 

@article{
author = "Božilović, Bojana and Nikolić, Bogdan and Waisi, Hadi and Trifković, Jelena and Dodevski, Vladimir and Janković, Bojan and Krstić, Sanja and Mojović, Miloš",
year = "2023",
abstract = "Brassinosteroids (BRs) are a class of plant hormones that play important roles in regulating various physiological and developmental processes in plants. One of the most effective BRs involved in modulating crop growth is 24-epibrassinolide (24-EBL). The effects of different concentrations of 24-EBL on various biochemical and biophysical parameters critical to early growth stages and seedling development were investigated using two maize hybrids, ‘ZP 434’ (a new-generation hybrid) and ‘ZP 704’ (an older-generation hybrid). The evaluation of results is based on measurements of germination percentage, morphometric parameters, redox status, comparative analysis of thermodynamic parameters (such as Gibbs free energy, enthalpy, entropy), and the concentration of specific sugars in different parts of maize seedlings. The results indicate that the germination and initial growth of maize seedlings are influenced by the flow of crucial sugars from the remaining seed (as a source of nutrients) towards the plumule and radicle (as sink organs). Furthermore, alterations in Gibbs free energy play a significant role in these sugar transfers within the maize seedlings. The seed germination was most affected by the highest concentrations of 24-EBL, showing inhibitory effects, whereas lower and moderate concentrations of exogenously added 24-EBL exhibited a beneficial influence on the initial phases of seedling growth. The mentioned approach gives new insights into source–sink relationships and can be used as a quantitative measure of the germination energy, which until now has been a qualitative criterion in seed science.",
journal = "Agronomy",
title = "Influence of 24-Epibrassinolide on the Energetic Parameters and Early Stages of Growth and Development in Seedlings of Two Maize (Zea mays L.) Genotypes",
volume = "13",
number = "7",
pages = "1673",
doi = "10.3390/agronomy13071673"
}

Božilović, B., Nikolić, B., Waisi, H., Trifković, J., Dodevski, V., Janković, B., Krstić, S.,& Mojović, M.. (2023). Influence of 24-Epibrassinolide on the Energetic Parameters and Early Stages of Growth and Development in Seedlings of Two Maize (Zea mays L.) Genotypes. in Agronomy, 13(7), 1673.
https://doi.org/10.3390/agronomy13071673

Božilović B, Nikolić B, Waisi H, Trifković J, Dodevski V, Janković B, Krstić S, Mojović M. Influence of 24-Epibrassinolide on the Energetic Parameters and Early Stages of Growth and Development in Seedlings of Two Maize (Zea mays L.) Genotypes. in Agronomy. 2023;13(7):1673.
doi:10.3390/agronomy13071673 .

Božilović, Bojana, Nikolić, Bogdan, Waisi, Hadi, Trifković, Jelena, Dodevski, Vladimir, Janković, Bojan, Krstić, Sanja, Mojović, Miloš, "Influence of 24-Epibrassinolide on the Energetic Parameters and Early Stages of Growth and Development in Seedlings of Two Maize (Zea mays L.) Genotypes" in Agronomy, 13, no. 7 (2023):1673,
https://doi.org/10.3390/agronomy13071673 . .

TY  - JOUR
AU  - Tadić, Marin
AU  - Panjan, Matjaž
AU  - Čekada, Miha
AU  - Jagličić, Zvonko
AU  - Pregelj, Matej
AU  - Spreitzer, Matjaž
AU  - Panjan, Peter
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12839
AB  - In the literature, a magnetic “easy” axis perpendicular to the film plane at room temperature (i.e., perpendicular magnetic anisotropy - PMA) has been reported in Ni (nickel) layers with thicknesses below ≈15 nm. In this work, we observed room-temperature PMA in a-Si/Ni/a-Si (where a-Si denotes amorphous silicon) thin film structures with nickel layer thicker than 15 nm. Two layered structures were prepared by DC/RF triode sputtering: [a-Si/Ni/a-Si] sandwich structure and [a-Si/Ni/a-Si]5 multilayer structure. The cross sectional STEM revealed uniform Ni layers with thicknesses of ≈17 nm in [a-Si/Ni/a-Si]5 – multilayer and ≈28 nm in [a-Si/Ni/a-Si] – single-layer whereas amorphous Si layers were ≈15 nm and 170 nm thick, respectively. An amorphous Ni–Si interphase was also observed in the layered structures. The XRD showed patterns for fcc-Ni with dominant (111) orientation. No other crystalline phases were observed in the XRD patterns. To our knowledge, there are no literature reports of easy magnetization direction perpendicular to the film plane at room temperature for Ni layers with thickness of ≈28 nm as presented in this work. The origin of PMA in a-Si/Ni/a-Si films may be mainly attributed to the magnetoelastic anisotropy whereas the secondary source of PMA is believed to be the surface anisotropy and magnetocrystalline anisotropy of [111] columnar grains. Amorphous silicon layers (substrate) do not have a well-defined lattice structure like crystalline substrates. Therefore, they do not induce strains in the nickel layers through lattice mismatch as in the case of epitaxy. The strains can be caused by other factors such as diffusion-induced strain, thermal expansion mismatch or intrinsic stresses during the growth process. These results could be important for applications in memory devices, sensors, logic chips, magneto-optic, magneto-electronic and spintronic devices and in fundamental research, as well as first step toward preparation and understanding of the PMA in thick nickel layers.
T2  - Ceramics International
T1  - Perpendicular magnetic anisotropy at room-temperature in sputtered a-Si/Ni/a-Si layered structure with thick Ni (nickel) layers
VL  - 49
IS  - 19
SP  - 32068
EP  - 32077
DO  - 10.1016/j.ceramint.2023.07.174
ER  - 

@article{
author = "Tadić, Marin and Panjan, Matjaž and Čekada, Miha and Jagličić, Zvonko and Pregelj, Matej and Spreitzer, Matjaž and Panjan, Peter",
year = "2023",
abstract = "In the literature, a magnetic “easy” axis perpendicular to the film plane at room temperature (i.e., perpendicular magnetic anisotropy - PMA) has been reported in Ni (nickel) layers with thicknesses below ≈15 nm. In this work, we observed room-temperature PMA in a-Si/Ni/a-Si (where a-Si denotes amorphous silicon) thin film structures with nickel layer thicker than 15 nm. Two layered structures were prepared by DC/RF triode sputtering: [a-Si/Ni/a-Si] sandwich structure and [a-Si/Ni/a-Si]5 multilayer structure. The cross sectional STEM revealed uniform Ni layers with thicknesses of ≈17 nm in [a-Si/Ni/a-Si]5 – multilayer and ≈28 nm in [a-Si/Ni/a-Si] – single-layer whereas amorphous Si layers were ≈15 nm and 170 nm thick, respectively. An amorphous Ni–Si interphase was also observed in the layered structures. The XRD showed patterns for fcc-Ni with dominant (111) orientation. No other crystalline phases were observed in the XRD patterns. To our knowledge, there are no literature reports of easy magnetization direction perpendicular to the film plane at room temperature for Ni layers with thickness of ≈28 nm as presented in this work. The origin of PMA in a-Si/Ni/a-Si films may be mainly attributed to the magnetoelastic anisotropy whereas the secondary source of PMA is believed to be the surface anisotropy and magnetocrystalline anisotropy of [111] columnar grains. Amorphous silicon layers (substrate) do not have a well-defined lattice structure like crystalline substrates. Therefore, they do not induce strains in the nickel layers through lattice mismatch as in the case of epitaxy. The strains can be caused by other factors such as diffusion-induced strain, thermal expansion mismatch or intrinsic stresses during the growth process. These results could be important for applications in memory devices, sensors, logic chips, magneto-optic, magneto-electronic and spintronic devices and in fundamental research, as well as first step toward preparation and understanding of the PMA in thick nickel layers.",
journal = "Ceramics International",
title = "Perpendicular magnetic anisotropy at room-temperature in sputtered a-Si/Ni/a-Si layered structure with thick Ni (nickel) layers",
volume = "49",
number = "19",
pages = "32068-32077",
doi = "10.1016/j.ceramint.2023.07.174"
}

Tadić, M., Panjan, M., Čekada, M., Jagličić, Z., Pregelj, M., Spreitzer, M.,& Panjan, P.. (2023). Perpendicular magnetic anisotropy at room-temperature in sputtered a-Si/Ni/a-Si layered structure with thick Ni (nickel) layers. in Ceramics International, 49(19), 32068-32077.
https://doi.org/10.1016/j.ceramint.2023.07.174

Tadić M, Panjan M, Čekada M, Jagličić Z, Pregelj M, Spreitzer M, Panjan P. Perpendicular magnetic anisotropy at room-temperature in sputtered a-Si/Ni/a-Si layered structure with thick Ni (nickel) layers. in Ceramics International. 2023;49(19):32068-32077.
doi:10.1016/j.ceramint.2023.07.174 .

Tadić, Marin, Panjan, Matjaž, Čekada, Miha, Jagličić, Zvonko, Pregelj, Matej, Spreitzer, Matjaž, Panjan, Peter, "Perpendicular magnetic anisotropy at room-temperature in sputtered a-Si/Ni/a-Si layered structure with thick Ni (nickel) layers" in Ceramics International, 49, no. 19 (2023):32068-32077,
https://doi.org/10.1016/j.ceramint.2023.07.174 . .

TY  - JOUR
AU  - Krunić, Matija
AU  - Ristić, Biljana
AU  - Bošnjak, Mihajlo
AU  - Paunović, Verica
AU  - Tovilović-Kovačević, Gordana
AU  - Zogović, Nevena
AU  - Mirčić, Aleksandar
AU  - Marković, Zoran
AU  - Todorović-Marković, Biljana
AU  - Jovanović, Svetlana P.
AU  - Kleut, Duška
AU  - Mojović, Miloš
AU  - Nakarada, Đura
AU  - Marković, Olivera
AU  - Vuković, Irena
AU  - Harhaji-Trajković, Ljubica
AU  - Trajković, Vladimir S.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9980
AB  - We investigated the ability of graphene quantum dot (GQD) nanoparticles to protect SH-SY5Y human neuroblastoma cells from oxidative/nitrosative stress induced by iron-nitrosyl complex sodium nitroprusside (SNP).GQD reduced SNP cytotoxicity by preventing mitochondrial depolarization, caspase-2 activation, and subsequent apoptotic death. Although GQD diminished the levels of nitric oxide (NO) in SNP-exposed cells, NO scavengers displayed only a slight protective effect, suggesting that NO quenching was not the main protective mechanism of GQD. GQD also reduced SNP-triggered increase in the intracellular levels of hydroxyl radical (•OH), superoxide anion (O2•- ), and lipid peroxidation. Nonselective antioxidants, •OH scavenging, and iron chelators, but not superoxide dismutase, mimicked GQD cytoprotective activity, indicating that GQD protect cells by neutralizing •OH generated in the presence of SNP-released iron. Cellular internalization of GQD was required for optimal protection, since a removal of extracellular GQD by extensive washing only partly diminished their protective effect. Moreover, GQD cooperated with SNP to induce autophagy, as confirmed by the inhibition of autophagylimiting Akt/PRAS40/mTOR signaling and increase in autophagy gene transcription, protein levels of proautophagic beclin-1 and LC3-II, formation of autophagic vesicles, and degradation of autophagic target p62. The antioxidant activity of GQD was not involved in autophagy induction, as antioxidants N-acetylcysteine and dimethyl sulfoxide failed to stimulate autophagy in SNP-exposed cells. Pharmacological inhibitors of early (wortmannin, 3-methyladenine) or late stages of autophagy (NH4Cl) efficiently reduced the protective effect of GQD. Therefore, the ability of GQD to prevent the in vitro neurotoxicity of SNP depends on both •OH/NO scavenging and induction of cytoprotective autophagy.
T2  - Free Radical Biology and Medicine
T1  - Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death
VL  - 177
SP  - 167
EP  - 180
DO  - 10.1016/j.freeradbiomed.2021.10.025
ER  - 

@article{
author = "Krunić, Matija and Ristić, Biljana and Bošnjak, Mihajlo and Paunović, Verica and Tovilović-Kovačević, Gordana and Zogović, Nevena and Mirčić, Aleksandar and Marković, Zoran and Todorović-Marković, Biljana and Jovanović, Svetlana P. and Kleut, Duška and Mojović, Miloš and Nakarada, Đura and Marković, Olivera and Vuković, Irena and Harhaji-Trajković, Ljubica and Trajković, Vladimir S.",
year = "2021",
abstract = "We investigated the ability of graphene quantum dot (GQD) nanoparticles to protect SH-SY5Y human neuroblastoma cells from oxidative/nitrosative stress induced by iron-nitrosyl complex sodium nitroprusside (SNP).GQD reduced SNP cytotoxicity by preventing mitochondrial depolarization, caspase-2 activation, and subsequent apoptotic death. Although GQD diminished the levels of nitric oxide (NO) in SNP-exposed cells, NO scavengers displayed only a slight protective effect, suggesting that NO quenching was not the main protective mechanism of GQD. GQD also reduced SNP-triggered increase in the intracellular levels of hydroxyl radical (•OH), superoxide anion (O2•- ), and lipid peroxidation. Nonselective antioxidants, •OH scavenging, and iron chelators, but not superoxide dismutase, mimicked GQD cytoprotective activity, indicating that GQD protect cells by neutralizing •OH generated in the presence of SNP-released iron. Cellular internalization of GQD was required for optimal protection, since a removal of extracellular GQD by extensive washing only partly diminished their protective effect. Moreover, GQD cooperated with SNP to induce autophagy, as confirmed by the inhibition of autophagylimiting Akt/PRAS40/mTOR signaling and increase in autophagy gene transcription, protein levels of proautophagic beclin-1 and LC3-II, formation of autophagic vesicles, and degradation of autophagic target p62. The antioxidant activity of GQD was not involved in autophagy induction, as antioxidants N-acetylcysteine and dimethyl sulfoxide failed to stimulate autophagy in SNP-exposed cells. Pharmacological inhibitors of early (wortmannin, 3-methyladenine) or late stages of autophagy (NH4Cl) efficiently reduced the protective effect of GQD. Therefore, the ability of GQD to prevent the in vitro neurotoxicity of SNP depends on both •OH/NO scavenging and induction of cytoprotective autophagy.",
journal = "Free Radical Biology and Medicine",
title = "Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death",
volume = "177",
pages = "167-180",
doi = "10.1016/j.freeradbiomed.2021.10.025"
}

Krunić, M., Ristić, B., Bošnjak, M., Paunović, V., Tovilović-Kovačević, G., Zogović, N., Mirčić, A., Marković, Z., Todorović-Marković, B., Jovanović, S. P., Kleut, D., Mojović, M., Nakarada, Đ., Marković, O., Vuković, I., Harhaji-Trajković, L.,& Trajković, V. S.. (2021). Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death. in Free Radical Biology and Medicine, 177, 167-180.
https://doi.org/10.1016/j.freeradbiomed.2021.10.025

Krunić M, Ristić B, Bošnjak M, Paunović V, Tovilović-Kovačević G, Zogović N, Mirčić A, Marković Z, Todorović-Marković B, Jovanović SP, Kleut D, Mojović M, Nakarada Đ, Marković O, Vuković I, Harhaji-Trajković L, Trajković VS. Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death. in Free Radical Biology and Medicine. 2021;177:167-180.
doi:10.1016/j.freeradbiomed.2021.10.025 .

Krunić, Matija, Ristić, Biljana, Bošnjak, Mihajlo, Paunović, Verica, Tovilović-Kovačević, Gordana, Zogović, Nevena, Mirčić, Aleksandar, Marković, Zoran, Todorović-Marković, Biljana, Jovanović, Svetlana P., Kleut, Duška, Mojović, Miloš, Nakarada, Đura, Marković, Olivera, Vuković, Irena, Harhaji-Trajković, Ljubica, Trajković, Vladimir S., "Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death" in Free Radical Biology and Medicine, 177 (2021):167-180,
https://doi.org/10.1016/j.freeradbiomed.2021.10.025 . .

TY  - JOUR
AU  - Cvjetinović, Đorđe
AU  - Prijović, Željko
AU  - Janković, Drina
AU  - Radović, Magdalena
AU  - Mirković, Marija D.
AU  - Milanović, Zorana
AU  - Mojović, Miloš
AU  - Škalamera, Đani
AU  - Vranješ-Đurić, Sanja
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9151
AB  - Liposomes are promising drug's delivery systems due to decreased toxicity of the liposome-encapsulated drug, but wider clinical application requires their more efficient tumor targeting with uptake, controlled drug release and higher shelf life. The unique metabolic characteristics of cancer cells based on higher demand for energy and therefore increased glucose utilization were exploited in the design of glucose modified liposomes (GML) with the aim to provide increased tumor targeting via glucose transporters and increased ability of drug delivery into tumor cells. Tumor accumulating potential of GML and non-glucose liposomes (NGL) were investigated on CT26 and LS174T tumor-bearing mice by simple and reliable radiotracer method using 177Lu as radioactive marker. Both liposomes, GML and NGL were radiolabeled in high radiolabeling yield, showing high in vitro stability in biological media, as the main prerequisite for the biodistribution studies. Tumors displayed significantly better accumulation of 177Lu-GML with the maximum uptake 6 h post-injection (5.8 ± 0.2%/g in LS174T tumor and 5.1 ± 0.5%/g in CT26 tumor), compared to negligible uptake of 177Lu-NGL (0.6 ± 0.1%/g in LS174T tumor and 0.9 ± 0.2%/g in CT26 tumor). Results of comparative biodistribution studies of 177Lu-NGL and 177Lu-GML indicate that increased accumulation of GML is enabled by glucose transporters and subsequent endocytosis, resulting in their prolonged retention in tumor tissues (up to 72 h). Direct radiolabeling of liposomes with 177Lu may be used not only for biodistribution studies using radiotracking, but also for cancer treatment. © 2021 Elsevier B.V.
T2  - Journal of Controlled Release
T1  - Bioevaluation of glucose-modified liposomes as a potential drug delivery system for cancer treatment using 177-Lu radiotracking
VL  - 332
SP  - 301
EP  - 311
DO  - 10.1016/j.jconrel.2021.03.006
ER  - 

@article{
author = "Cvjetinović, Đorđe and Prijović, Željko and Janković, Drina and Radović, Magdalena and Mirković, Marija D. and Milanović, Zorana and Mojović, Miloš and Škalamera, Đani and Vranješ-Đurić, Sanja",
year = "2021",
abstract = "Liposomes are promising drug's delivery systems due to decreased toxicity of the liposome-encapsulated drug, but wider clinical application requires their more efficient tumor targeting with uptake, controlled drug release and higher shelf life. The unique metabolic characteristics of cancer cells based on higher demand for energy and therefore increased glucose utilization were exploited in the design of glucose modified liposomes (GML) with the aim to provide increased tumor targeting via glucose transporters and increased ability of drug delivery into tumor cells. Tumor accumulating potential of GML and non-glucose liposomes (NGL) were investigated on CT26 and LS174T tumor-bearing mice by simple and reliable radiotracer method using 177Lu as radioactive marker. Both liposomes, GML and NGL were radiolabeled in high radiolabeling yield, showing high in vitro stability in biological media, as the main prerequisite for the biodistribution studies. Tumors displayed significantly better accumulation of 177Lu-GML with the maximum uptake 6 h post-injection (5.8 ± 0.2%/g in LS174T tumor and 5.1 ± 0.5%/g in CT26 tumor), compared to negligible uptake of 177Lu-NGL (0.6 ± 0.1%/g in LS174T tumor and 0.9 ± 0.2%/g in CT26 tumor). Results of comparative biodistribution studies of 177Lu-NGL and 177Lu-GML indicate that increased accumulation of GML is enabled by glucose transporters and subsequent endocytosis, resulting in their prolonged retention in tumor tissues (up to 72 h). Direct radiolabeling of liposomes with 177Lu may be used not only for biodistribution studies using radiotracking, but also for cancer treatment. © 2021 Elsevier B.V.",
journal = "Journal of Controlled Release",
title = "Bioevaluation of glucose-modified liposomes as a potential drug delivery system for cancer treatment using 177-Lu radiotracking",
volume = "332",
pages = "301-311",
doi = "10.1016/j.jconrel.2021.03.006"
}

Cvjetinović, Đ., Prijović, Ž., Janković, D., Radović, M., Mirković, M. D., Milanović, Z., Mojović, M., Škalamera, Đ.,& Vranješ-Đurić, S.. (2021). Bioevaluation of glucose-modified liposomes as a potential drug delivery system for cancer treatment using 177-Lu radiotracking. in Journal of Controlled Release, 332, 301-311.
https://doi.org/10.1016/j.jconrel.2021.03.006

Cvjetinović Đ, Prijović Ž, Janković D, Radović M, Mirković MD, Milanović Z, Mojović M, Škalamera Đ, Vranješ-Đurić S. Bioevaluation of glucose-modified liposomes as a potential drug delivery system for cancer treatment using 177-Lu radiotracking. in Journal of Controlled Release. 2021;332:301-311.
doi:10.1016/j.jconrel.2021.03.006 .

Cvjetinović, Đorđe, Prijović, Željko, Janković, Drina, Radović, Magdalena, Mirković, Marija D., Milanović, Zorana, Mojović, Miloš, Škalamera, Đani, Vranješ-Đurić, Sanja, "Bioevaluation of glucose-modified liposomes as a potential drug delivery system for cancer treatment using 177-Lu radiotracking" in Journal of Controlled Release, 332 (2021):301-311,
https://doi.org/10.1016/j.jconrel.2021.03.006 . .

TY  - JOUR
AU  - Rajić, Vladimir
AU  - Simatović Stojković, Ivana
AU  - Veselinović, Ljiljana M.
AU  - Belošević-Čavor, Jelena
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Škapin, Srečo Davor
AU  - Mojović, Miloš
AU  - Stojadinović, Stevan
AU  - Rac, Vladislav
AU  - Častvan Janković, Ivona
AU  - Marković, Smilja
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9679
AB  - Eco-friendly and rapid microwave processing of a precipitate was used to produce Fe-doped zinc oxide (Zn1−xFexO, x = 0, 0.05, 0.1, 0.15 and 0.20; ZnO:Fe) nanoparticles, which were tested as catalysts toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in a moderately alkaline solution. The phase composition, crystal structure, morphology, textural properties, surface chemistry, optical properties and band structure were examined to comprehend the influence of Zn2+ partial substitution with Fe3+ on the catalytic activity of ZnO:Fe. Linear sweep voltammetry showed an improved catalytic activity of ZnO:5Fe toward the ORR, compared to pure ZnO, while with increased amounts of the Fe-dopant the activity decreased. The improvement was suggested by a more positive onset potential (0.394 V vs. RHE), current density (0.231 mA cm−2 at 0.150 V vs. RHE), and faster kinetics (Tafel slope, b = 248 mV dec−1), and it may be due to the synergistic effect of (1) a sufficient amount of surface oxygen vacancies, and (2) a certain amount of plate-like particles composed of crystallites with well developed (0001) and (000) facets. Quite the contrary, the OER study showed that the introduction of Fe3+ ions into the ZnO crystal structure resulted in enhanced catalytic activity of all ZnO:Fe samples, compared to pure ZnO, probably due to the modified binding energy and an optimized band structure. With the maximal current density of 1.066 mA cm−2 at 2.216 V vs. RHE, an onset potential of 1.856 V vs. RHE, and the smallest potential difference between the OER and ORR (ΔE = 1.58 V), ZnO:10Fe may be considered a promising bifunctional catalyst toward the OER/ORR in moderately alkaline solution. This study demonstrates that the electrocatalytic activity of ZnO:Fe strongly depends on the defect chemistry and consequently the band structure. Along with providing fundamental insight into the electrocatalytic activity of ZnO:Fe, the study also indicates an optimal stoichiometry for enhanced bifunctional activity toward the OER/ORR, compared to pure ZnO.
T2  - Physical Chemistry Chemical Physics
T1  - Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry
VL  - 22
IS  - 38
SP  - 22078
EP  - 22095
DO  - 10.1039/D0CP03377D
ER  - 

@article{
author = "Rajić, Vladimir and Simatović Stojković, Ivana and Veselinović, Ljiljana M. and Belošević-Čavor, Jelena and Novaković, Mirjana M. and Popović, Maja and Škapin, Srečo Davor and Mojović, Miloš and Stojadinović, Stevan and Rac, Vladislav and Častvan Janković, Ivona and Marković, Smilja",
year = "2020",
abstract = "Eco-friendly and rapid microwave processing of a precipitate was used to produce Fe-doped zinc oxide (Zn1−xFexO, x = 0, 0.05, 0.1, 0.15 and 0.20; ZnO:Fe) nanoparticles, which were tested as catalysts toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in a moderately alkaline solution. The phase composition, crystal structure, morphology, textural properties, surface chemistry, optical properties and band structure were examined to comprehend the influence of Zn2+ partial substitution with Fe3+ on the catalytic activity of ZnO:Fe. Linear sweep voltammetry showed an improved catalytic activity of ZnO:5Fe toward the ORR, compared to pure ZnO, while with increased amounts of the Fe-dopant the activity decreased. The improvement was suggested by a more positive onset potential (0.394 V vs. RHE), current density (0.231 mA cm−2 at 0.150 V vs. RHE), and faster kinetics (Tafel slope, b = 248 mV dec−1), and it may be due to the synergistic effect of (1) a sufficient amount of surface oxygen vacancies, and (2) a certain amount of plate-like particles composed of crystallites with well developed (0001) and (000) facets. Quite the contrary, the OER study showed that the introduction of Fe3+ ions into the ZnO crystal structure resulted in enhanced catalytic activity of all ZnO:Fe samples, compared to pure ZnO, probably due to the modified binding energy and an optimized band structure. With the maximal current density of 1.066 mA cm−2 at 2.216 V vs. RHE, an onset potential of 1.856 V vs. RHE, and the smallest potential difference between the OER and ORR (ΔE = 1.58 V), ZnO:10Fe may be considered a promising bifunctional catalyst toward the OER/ORR in moderately alkaline solution. This study demonstrates that the electrocatalytic activity of ZnO:Fe strongly depends on the defect chemistry and consequently the band structure. Along with providing fundamental insight into the electrocatalytic activity of ZnO:Fe, the study also indicates an optimal stoichiometry for enhanced bifunctional activity toward the OER/ORR, compared to pure ZnO.",
journal = "Physical Chemistry Chemical Physics",
title = "Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry",
volume = "22",
number = "38",
pages = "22078-22095",
doi = "10.1039/D0CP03377D"
}

Rajić, V., Simatović Stojković, I., Veselinović, L. M., Belošević-Čavor, J., Novaković, M. M., Popović, M., Škapin, S. D., Mojović, M., Stojadinović, S., Rac, V., Častvan Janković, I.,& Marković, S.. (2020). Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry. in Physical Chemistry Chemical Physics, 22(38), 22078-22095.
https://doi.org/10.1039/D0CP03377D

Rajić V, Simatović Stojković I, Veselinović LM, Belošević-Čavor J, Novaković MM, Popović M, Škapin SD, Mojović M, Stojadinović S, Rac V, Častvan Janković I, Marković S. Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry. in Physical Chemistry Chemical Physics. 2020;22(38):22078-22095.
doi:10.1039/D0CP03377D .

Rajić, Vladimir, Simatović Stojković, Ivana, Veselinović, Ljiljana M., Belošević-Čavor, Jelena, Novaković, Mirjana M., Popović, Maja, Škapin, Srečo Davor, Mojović, Miloš, Stojadinović, Stevan, Rac, Vladislav, Častvan Janković, Ivona, Marković, Smilja, "Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry" in Physical Chemistry Chemical Physics, 22, no. 38 (2020):22078-22095,
https://doi.org/10.1039/D0CP03377D . .