TY  - JOUR
AU  - Vasiljevic, Zorka
AU  - Vunduk, Jovana
AU  - Bartolić, Dragana
AU  - Mišković, Goran
AU  - Ognjanović, Miloš
AU  - Tadić, Nenad B.
AU  - Nikolić, Maria Vesna
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13189
AB  - Emission of greenhouse gases and infectious diseases caused by improper agro-waste disposal has gained significant attention in recent years. To overcome these hurdles, agro-waste can be valorized into valuable bioactive compounds that act as reducing or stabilizing agents in the synthesis of nanomaterials. Herein, we report a simple circular approach using Citrus reticulata Blanco (C. reticulata) waste (peel powder/aqueous extract) as green reducing and capping/stabilizing agents and Zn nitrate/acetate precursors to synthesize ZnO nanoparticles (NPs) with efficient antimicrobial and photocatalytic activities. The obtained NPs crystallized in a hexagonal wurtzite structure and differed clearly in their morphology. UV-vis analysis of the nanoparticles showed a characteristic broad absorption band between 330 and 414 nm belonging to ZnO NPs. Fourier transform infrared (FTIR) spectroscopy of ZnO NPs exhibited a Zn-O band close to 450 cm-1. The band gap values were in the range of 2.84-3.14 eV depending on the precursor and agent used. The crystallite size obtained from size-strain plots from measured XRD patterns was between 7 and 26 nm, with strain between 16 and 4%. The highly crystalline nature of obtained ZnO NPs was confirmed by clear ring diffraction patterns and d-spacing values of the observed lattice fringes. ZnNPeelMan_400 and ZnNExtrMan showed good stability, as the zeta potential was found to be around −20 mV, and reduced particle aggregation. Photoluminescence analysis revealed different defects belonging to oxygen vacancies (VO+ and VO+2) and zinc interstitial (Zni) sites. The presence of oxygen vacancies on the surface of ZnAcExtrMan_400 and ZnAcPeelMan_400 increased antimicrobial activity, specifically against Gram-negative bacteria Escherichia coli (E. coli) and Salmonella enteritidis (S. enteritidis). ZnNExtrMan with a minimal inhibitory concentration of 0.156 mg/mL was more effective against Gram-positive bacteria Staphylococcus aureus (S. aureus), revealing a high influence of particle size and shape on antimicrobial activity. In addition, the photocatalytic activity of the ZnO NPs was examined by assessing the degradation of acid green dye in an aqueous solution under UV light irradiation. ZnAcPeelMan_400 exhibited excellent photocatalytic activity (94%) within 90 min after irradiation compared to other obtained ZnO NPs.
T2  - ACS Applied Bio Materials
T1  - An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity
DO  - 10.1021/acsabm.4c00079
ER  - 

@article{
author = "Vasiljevic, Zorka and Vunduk, Jovana and Bartolić, Dragana and Mišković, Goran and Ognjanović, Miloš and Tadić, Nenad B. and Nikolić, Maria Vesna",
year = "2024",
abstract = "Emission of greenhouse gases and infectious diseases caused by improper agro-waste disposal has gained significant attention in recent years. To overcome these hurdles, agro-waste can be valorized into valuable bioactive compounds that act as reducing or stabilizing agents in the synthesis of nanomaterials. Herein, we report a simple circular approach using Citrus reticulata Blanco (C. reticulata) waste (peel powder/aqueous extract) as green reducing and capping/stabilizing agents and Zn nitrate/acetate precursors to synthesize ZnO nanoparticles (NPs) with efficient antimicrobial and photocatalytic activities. The obtained NPs crystallized in a hexagonal wurtzite structure and differed clearly in their morphology. UV-vis analysis of the nanoparticles showed a characteristic broad absorption band between 330 and 414 nm belonging to ZnO NPs. Fourier transform infrared (FTIR) spectroscopy of ZnO NPs exhibited a Zn-O band close to 450 cm-1. The band gap values were in the range of 2.84-3.14 eV depending on the precursor and agent used. The crystallite size obtained from size-strain plots from measured XRD patterns was between 7 and 26 nm, with strain between 16 and 4%. The highly crystalline nature of obtained ZnO NPs was confirmed by clear ring diffraction patterns and d-spacing values of the observed lattice fringes. ZnNPeelMan_400 and ZnNExtrMan showed good stability, as the zeta potential was found to be around −20 mV, and reduced particle aggregation. Photoluminescence analysis revealed different defects belonging to oxygen vacancies (VO+ and VO+2) and zinc interstitial (Zni) sites. The presence of oxygen vacancies on the surface of ZnAcExtrMan_400 and ZnAcPeelMan_400 increased antimicrobial activity, specifically against Gram-negative bacteria Escherichia coli (E. coli) and Salmonella enteritidis (S. enteritidis). ZnNExtrMan with a minimal inhibitory concentration of 0.156 mg/mL was more effective against Gram-positive bacteria Staphylococcus aureus (S. aureus), revealing a high influence of particle size and shape on antimicrobial activity. In addition, the photocatalytic activity of the ZnO NPs was examined by assessing the degradation of acid green dye in an aqueous solution under UV light irradiation. ZnAcPeelMan_400 exhibited excellent photocatalytic activity (94%) within 90 min after irradiation compared to other obtained ZnO NPs.",
journal = "ACS Applied Bio Materials",
title = "An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity",
doi = "10.1021/acsabm.4c00079"
}

Vasiljevic, Z., Vunduk, J., Bartolić, D., Mišković, G., Ognjanović, M., Tadić, N. B.,& Nikolić, M. V.. (2024). An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity. in ACS Applied Bio Materials.
https://doi.org/10.1021/acsabm.4c00079

Vasiljevic Z, Vunduk J, Bartolić D, Mišković G, Ognjanović M, Tadić NB, Nikolić MV. An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity. in ACS Applied Bio Materials. 2024;.
doi:10.1021/acsabm.4c00079 .

Vasiljevic, Zorka, Vunduk, Jovana, Bartolić, Dragana, Mišković, Goran, Ognjanović, Miloš, Tadić, Nenad B., Nikolić, Maria Vesna, "An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity" in ACS Applied Bio Materials (2024),
https://doi.org/10.1021/acsabm.4c00079 . .

TY  - JOUR
AU  - Ahmetović, Sanita
AU  - Vasiljević, Zorka Ž.
AU  - Rajić, Vladimir
AU  - Bartolić, Dragana
AU  - Novaković, Mirjana M.
AU  - Tadić, Nenad B.
AU  - Cvjetićanin, Nikola
AU  - Nikolić, Maria Vesna
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10448
AB  - Pure and samarium (Sm3+) - or zirconium (Zr4+)-doped TiO2 nanofibers were synthesized by electrospinning method followed by calcination at 500 °C for 1 h. As-spun fibers were smooth, straight and continuous, whilst EDS analysis confirmed the fiber composition and incorporation of dopants in the fibers. Doping with Sm3+ and Zr4+ greatly inhibited the phase transformation of anatase to rutile, by surrounding of Sm3+ ions through formation of Ti-O-Sm bonds and by replacement of Ti4+ ions with larger Zr4+ ions. This was confirmed by HRTEM and SAED analysis. The size of nanofibers was determined to be 133 nm, 175 nm and 155 nm for pure, (0.5%)Sm3+:TiO2 and (1%)Zr4+:TiO2, respectively. After calcination, TiO2 crystal lattice with interplanar spacing of 0.353 nm of (101) crystal plane was not significantly disturbed by Sm doping whilst crystal lattice spacing of 0.357 nm of (101) planes of anatase phase in case TiO2:1.0%Zr4+, significantly differs from the value of pure TiO2 (0.352 nm), thus implying that Zr was doped into substitutional sites of the TiO2 lattice. The indirect band gaps were calculated to be in the range 3.07–3.24 eV. TiO2:0.5%Sm3+ and TiO2:1.0%Zr4+ exhibited higher specific surface area, of 47.1 and 59.4 m2/g, respectively, than pure TiO2 fibers (19.7 m2/g). Effects of Sm3+ and Zr4+ dopant content on the photodegradation efficiency of methylene blue (MB) were studied. TiO2:0.5%Sm3+ and TiO2:1.0%Zr4+ nanofibers have shown the highest photocatalytic activity of 97% and 98% with constant rates 0.01768 min−1 and 0.01939 min−1, respectively, within180 min irradiation under visible light.
T2  - Journal of Alloys and Compounds
T1  - Examination of the doping effects of samarium (Sm3+) and zirconium (Zr4+) on the photocatalytic activity of TiO2 nanofibers
VL  - 930
SP  - 167423
DO  - 10.1016/j.jallcom.2022.167423
ER  - 

@article{
author = "Ahmetović, Sanita and Vasiljević, Zorka Ž. and Rajić, Vladimir and Bartolić, Dragana and Novaković, Mirjana M. and Tadić, Nenad B. and Cvjetićanin, Nikola and Nikolić, Maria Vesna",
year = "2023",
abstract = "Pure and samarium (Sm3+) - or zirconium (Zr4+)-doped TiO2 nanofibers were synthesized by electrospinning method followed by calcination at 500 °C for 1 h. As-spun fibers were smooth, straight and continuous, whilst EDS analysis confirmed the fiber composition and incorporation of dopants in the fibers. Doping with Sm3+ and Zr4+ greatly inhibited the phase transformation of anatase to rutile, by surrounding of Sm3+ ions through formation of Ti-O-Sm bonds and by replacement of Ti4+ ions with larger Zr4+ ions. This was confirmed by HRTEM and SAED analysis. The size of nanofibers was determined to be 133 nm, 175 nm and 155 nm for pure, (0.5%)Sm3+:TiO2 and (1%)Zr4+:TiO2, respectively. After calcination, TiO2 crystal lattice with interplanar spacing of 0.353 nm of (101) crystal plane was not significantly disturbed by Sm doping whilst crystal lattice spacing of 0.357 nm of (101) planes of anatase phase in case TiO2:1.0%Zr4+, significantly differs from the value of pure TiO2 (0.352 nm), thus implying that Zr was doped into substitutional sites of the TiO2 lattice. The indirect band gaps were calculated to be in the range 3.07–3.24 eV. TiO2:0.5%Sm3+ and TiO2:1.0%Zr4+ exhibited higher specific surface area, of 47.1 and 59.4 m2/g, respectively, than pure TiO2 fibers (19.7 m2/g). Effects of Sm3+ and Zr4+ dopant content on the photodegradation efficiency of methylene blue (MB) were studied. TiO2:0.5%Sm3+ and TiO2:1.0%Zr4+ nanofibers have shown the highest photocatalytic activity of 97% and 98% with constant rates 0.01768 min−1 and 0.01939 min−1, respectively, within180 min irradiation under visible light.",
journal = "Journal of Alloys and Compounds",
title = "Examination of the doping effects of samarium (Sm3+) and zirconium (Zr4+) on the photocatalytic activity of TiO2 nanofibers",
volume = "930",
pages = "167423",
doi = "10.1016/j.jallcom.2022.167423"
}

Ahmetović, S., Vasiljević, Z. Ž., Rajić, V., Bartolić, D., Novaković, M. M., Tadić, N. B., Cvjetićanin, N.,& Nikolić, M. V.. (2023). Examination of the doping effects of samarium (Sm3+) and zirconium (Zr4+) on the photocatalytic activity of TiO2 nanofibers. in Journal of Alloys and Compounds, 930, 167423.
https://doi.org/10.1016/j.jallcom.2022.167423

Ahmetović S, Vasiljević ZŽ, Rajić V, Bartolić D, Novaković MM, Tadić NB, Cvjetićanin N, Nikolić MV. Examination of the doping effects of samarium (Sm3+) and zirconium (Zr4+) on the photocatalytic activity of TiO2 nanofibers. in Journal of Alloys and Compounds. 2023;930:167423.
doi:10.1016/j.jallcom.2022.167423 .

Ahmetović, Sanita, Vasiljević, Zorka Ž., Rajić, Vladimir, Bartolić, Dragana, Novaković, Mirjana M., Tadić, Nenad B., Cvjetićanin, Nikola, Nikolić, Maria Vesna, "Examination of the doping effects of samarium (Sm3+) and zirconium (Zr4+) on the photocatalytic activity of TiO2 nanofibers" in Journal of Alloys and Compounds, 930 (2023):167423,
https://doi.org/10.1016/j.jallcom.2022.167423 . .

TY  - JOUR
AU  - Vasiljević, Zorka
AU  - Dojčinović, Milena
AU  - Vujančević, Jelena
AU  - Janković-Častvan, Ivona
AU  - Ognjanović, Miloš
AU  - Tadić, Nenad B.
AU  - Stojadinović, Stevan
AU  - Branković, Goran O.
AU  - Nikolić, Maria Vesna
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9706
AB  - The aim of this work was to synthesize semiconducting oxide nanoparticles using a simple method with low production cost to be applied in natural sunlight for photocatalytic degradation of pollutants in waste water. Iron titanate (Fe2TiO5) nanoparticles with an orthorhombic structure were successfully synthesized using a modified sol–gel method and calcination at 750°C. The as-prepared Fe2TiO5 nanoparticles exhibited a moderate specific surface area. The mesoporous Fe2TiO5 nanoparticles possessed strong absorption in the visible-light region and the band gap was estimated to be around 2.16 eV. The photocatalytic activity was evaluated by the degradation of methylene blue under natural sunlight. The effect of parameters such as the amount of catalyst, initial concentration of the dye and pH of the dye solution on the removal efficiency of methylene blue was investigated. Fe2TiO5 showed high degradation efficiency in a strong alkaline medium that can be the result of the facilitated formation of OH radicals due to an increased concentration of hydroxyl ions.
T2  - Royal Society Open Science
T1  - Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method
VL  - 7
IS  - 9
SP  - 200708
DO  - 10.1098/rsos.200708
ER  - 

@article{
author = "Vasiljević, Zorka and Dojčinović, Milena and Vujančević, Jelena and Janković-Častvan, Ivona and Ognjanović, Miloš and Tadić, Nenad B. and Stojadinović, Stevan and Branković, Goran O. and Nikolić, Maria Vesna",
year = "2020",
abstract = "The aim of this work was to synthesize semiconducting oxide nanoparticles using a simple method with low production cost to be applied in natural sunlight for photocatalytic degradation of pollutants in waste water. Iron titanate (Fe2TiO5) nanoparticles with an orthorhombic structure were successfully synthesized using a modified sol–gel method and calcination at 750°C. The as-prepared Fe2TiO5 nanoparticles exhibited a moderate specific surface area. The mesoporous Fe2TiO5 nanoparticles possessed strong absorption in the visible-light region and the band gap was estimated to be around 2.16 eV. The photocatalytic activity was evaluated by the degradation of methylene blue under natural sunlight. The effect of parameters such as the amount of catalyst, initial concentration of the dye and pH of the dye solution on the removal efficiency of methylene blue was investigated. Fe2TiO5 showed high degradation efficiency in a strong alkaline medium that can be the result of the facilitated formation of OH radicals due to an increased concentration of hydroxyl ions.",
journal = "Royal Society Open Science",
title = "Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method",
volume = "7",
number = "9",
pages = "200708",
doi = "10.1098/rsos.200708"
}

Vasiljević, Z., Dojčinović, M., Vujančević, J., Janković-Častvan, I., Ognjanović, M., Tadić, N. B., Stojadinović, S., Branković, G. O.,& Nikolić, M. V.. (2020). Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method. in Royal Society Open Science, 7(9), 200708.
https://doi.org/10.1098/rsos.200708

Vasiljević Z, Dojčinović M, Vujančević J, Janković-Častvan I, Ognjanović M, Tadić NB, Stojadinović S, Branković GO, Nikolić MV. Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method. in Royal Society Open Science. 2020;7(9):200708.
doi:10.1098/rsos.200708 .

Vasiljević, Zorka, Dojčinović, Milena, Vujančević, Jelena, Janković-Častvan, Ivona, Ognjanović, Miloš, Tadić, Nenad B., Stojadinović, Stevan, Branković, Goran O., Nikolić, Maria Vesna, "Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method" in Royal Society Open Science, 7, no. 9 (2020):200708,
https://doi.org/10.1098/rsos.200708 . .