TY  - JOUR
AU  - Dohcevic-Mitrovic, Z. D.
AU  - Paunović, Novica M.
AU  - Matović, Branko
AU  - Osiceanu, P.
AU  - Scurtu, R.
AU  - Askrabic, S.
AU  - Radović, Marko B.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/505
AB  - Y-doped HfO2 nanopowders, produced by metathesis synthesis, exhibit ferromagnetism at room temperature. The X-ray diffraction and Raman measurements have shown that HfO2 nanopowders undergo phase transformation from monoclinic to tetragonal and cubic phase with increasing of Y content. The X-ray photoelectron spectroscopy and Raman analysis gave evidence that Y-doped HfO2 nanopowders are oxygen deficient. The ferromagnetic properties of Y-doped HfO2 nanocrystals are dependent on crystal structure changes. The structural transformation from monoclinic to tetragonal phase with Y doping is followed by increased ferromagnetic ordering because of the increased concentration of oxygen vacancies (V-O) in different charge states. Higher Y content favors the formation of cubic phase and the ferromagnetism significantly weakens. In cubic hafnia phase, yttrium can form (V-O-Y-Hf) defect complexes in different charge states. The appearance of these complexes can be responsible for the degradation of ferromagnetic ordering. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
T2  - Ceramics International
T1  - Structural dependent room-temperature ferromagnetism in yttrium doped HfO2 nanoparticles
VL  - 41
IS  - 5
SP  - 6970
EP  - 6977
DO  - 10.1016/j.ceramint.2015.02.002
ER  - 

@article{
author = "Dohcevic-Mitrovic, Z. D. and Paunović, Novica M. and Matović, Branko and Osiceanu, P. and Scurtu, R. and Askrabic, S. and Radović, Marko B.",
year = "2015",
abstract = "Y-doped HfO2 nanopowders, produced by metathesis synthesis, exhibit ferromagnetism at room temperature. The X-ray diffraction and Raman measurements have shown that HfO2 nanopowders undergo phase transformation from monoclinic to tetragonal and cubic phase with increasing of Y content. The X-ray photoelectron spectroscopy and Raman analysis gave evidence that Y-doped HfO2 nanopowders are oxygen deficient. The ferromagnetic properties of Y-doped HfO2 nanocrystals are dependent on crystal structure changes. The structural transformation from monoclinic to tetragonal phase with Y doping is followed by increased ferromagnetic ordering because of the increased concentration of oxygen vacancies (V-O) in different charge states. Higher Y content favors the formation of cubic phase and the ferromagnetism significantly weakens. In cubic hafnia phase, yttrium can form (V-O-Y-Hf) defect complexes in different charge states. The appearance of these complexes can be responsible for the degradation of ferromagnetic ordering. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.",
journal = "Ceramics International",
title = "Structural dependent room-temperature ferromagnetism in yttrium doped HfO2 nanoparticles",
volume = "41",
number = "5",
pages = "6970-6977",
doi = "10.1016/j.ceramint.2015.02.002"
}

Dohcevic-Mitrovic, Z. D., Paunović, N. M., Matović, B., Osiceanu, P., Scurtu, R., Askrabic, S.,& Radović, M. B.. (2015). Structural dependent room-temperature ferromagnetism in yttrium doped HfO2 nanoparticles. in Ceramics International, 41(5), 6970-6977.
https://doi.org/10.1016/j.ceramint.2015.02.002

Dohcevic-Mitrovic ZD, Paunović NM, Matović B, Osiceanu P, Scurtu R, Askrabic S, Radović MB. Structural dependent room-temperature ferromagnetism in yttrium doped HfO2 nanoparticles. in Ceramics International. 2015;41(5):6970-6977.
doi:10.1016/j.ceramint.2015.02.002 .

Dohcevic-Mitrovic, Z. D., Paunović, Novica M., Matović, Branko, Osiceanu, P., Scurtu, R., Askrabic, S., Radović, Marko B., "Structural dependent room-temperature ferromagnetism in yttrium doped HfO2 nanoparticles" in Ceramics International, 41, no. 5 (2015):6970-6977,
https://doi.org/10.1016/j.ceramint.2015.02.002 . .

TY  - JOUR
AU  - Stojanović, Danka
AU  - Matkovic, A.
AU  - Askrabic, S.
AU  - Beltaos, A.
AU  - Ralević, Uroš
AU  - Jovanović, Đorđe
AU  - Bajuk-Bogdanović, Danica V.
AU  - Holclajtner-Antunović, Ivanka D.
AU  - Gajic, R.
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7017
AB  - In this study, graphene samples prepared by mechanical exfoliation were examined by Raman spectroscopy. The Au electrical contacts, fabricated using photolithography, allowed the application of a gate voltage between graphene and the Si substrate. In the Raman spectra of the sample, we observed shifts of position, changes of intensity and the width variations of the G and 2D peaks with the change of the gate voltage. Spatial Raman mapping of the samples was performed showing variations in intensities of the Raman peaks in different flake regions.
T2  - Physica Scripta
T1  - Raman spectroscopy of graphene: doping and mapping
VL  - T157
DO  - 10.1088/0031-8949/2013/T157/014010
ER  - 

@article{
author = "Stojanović, Danka and Matkovic, A. and Askrabic, S. and Beltaos, A. and Ralević, Uroš and Jovanović, Đorđe and Bajuk-Bogdanović, Danica V. and Holclajtner-Antunović, Ivanka D. and Gajic, R.",
year = "2013",
abstract = "In this study, graphene samples prepared by mechanical exfoliation were examined by Raman spectroscopy. The Au electrical contacts, fabricated using photolithography, allowed the application of a gate voltage between graphene and the Si substrate. In the Raman spectra of the sample, we observed shifts of position, changes of intensity and the width variations of the G and 2D peaks with the change of the gate voltage. Spatial Raman mapping of the samples was performed showing variations in intensities of the Raman peaks in different flake regions.",
journal = "Physica Scripta",
title = "Raman spectroscopy of graphene: doping and mapping",
volume = "T157",
doi = "10.1088/0031-8949/2013/T157/014010"
}

Stojanović, D., Matkovic, A., Askrabic, S., Beltaos, A., Ralević, U., Jovanović, Đ., Bajuk-Bogdanović, D. V., Holclajtner-Antunović, I. D.,& Gajic, R.. (2013). Raman spectroscopy of graphene: doping and mapping. in Physica Scripta, T157.
https://doi.org/10.1088/0031-8949/2013/T157/014010

Stojanović D, Matkovic A, Askrabic S, Beltaos A, Ralević U, Jovanović Đ, Bajuk-Bogdanović DV, Holclajtner-Antunović ID, Gajic R. Raman spectroscopy of graphene: doping and mapping. in Physica Scripta. 2013;T157.
doi:10.1088/0031-8949/2013/T157/014010 .

Stojanović, Danka, Matkovic, A., Askrabic, S., Beltaos, A., Ralević, Uroš, Jovanović, Đorđe, Bajuk-Bogdanović, Danica V., Holclajtner-Antunović, Ivanka D., Gajic, R., "Raman spectroscopy of graphene: doping and mapping" in Physica Scripta, T157 (2013),
https://doi.org/10.1088/0031-8949/2013/T157/014010 . .

TY  - JOUR
AU  - Askrabic, S.
AU  - Dohcevic-Mitrovic, Z.
AU  - Kremenović, Aleksandar S.
AU  - Lazarević, Nataša
AU  - Kahlenberg, V.
AU  - Popović, Zoran V.
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4661
AB  - Nanocrystalline ceria (CeO2) is known for its ionic conductivity and oxygen storage properties, which depend on the presence of oxygen ion vacancies. The vacancies cause several important changes in CeO2 involving microstrain, electronic structure, magnetic properties, etc. In this article, we focus our attention to the microstructural changes of nanocrystalline CeO2-x annealed at different temperatures in the range 200500 degrees C. Structural and vibrational properties were investigated by X-ray diffraction and Raman spectroscopy. It was observed that the content of oxygen vacancies changed significantly with increasing annealing temperature, which plays an important role in the observed microstructural changes of the annealed samples. We demonstrate that the observed microstrain changes, because of variable defect content, dominate over the crystallite size effect. This finding is opposite to the conclusions made by several other authors. A new mode, classified as a probable surface mode, was observed in the Raman spectra at similar to 480 cm(1), the appearance of which can be explained by the large defective structure and disorder in the ceria lattice. Copyright (c) 2011 John Wiley and Sons, Ltd.
T2  - Journal of Raman Spectroscopy
T1  - Oxygen vacancy-induced microstructural changes of annealed CeO2-x nanocrystals
VL  - 43
IS  - 1
SP  - 76
EP  - 81
DO  - 10.1002/jrs.2987
ER  - 

@article{
author = "Askrabic, S. and Dohcevic-Mitrovic, Z. and Kremenović, Aleksandar S. and Lazarević, Nataša and Kahlenberg, V. and Popović, Zoran V.",
year = "2012",
abstract = "Nanocrystalline ceria (CeO2) is known for its ionic conductivity and oxygen storage properties, which depend on the presence of oxygen ion vacancies. The vacancies cause several important changes in CeO2 involving microstrain, electronic structure, magnetic properties, etc. In this article, we focus our attention to the microstructural changes of nanocrystalline CeO2-x annealed at different temperatures in the range 200500 degrees C. Structural and vibrational properties were investigated by X-ray diffraction and Raman spectroscopy. It was observed that the content of oxygen vacancies changed significantly with increasing annealing temperature, which plays an important role in the observed microstructural changes of the annealed samples. We demonstrate that the observed microstrain changes, because of variable defect content, dominate over the crystallite size effect. This finding is opposite to the conclusions made by several other authors. A new mode, classified as a probable surface mode, was observed in the Raman spectra at similar to 480 cm(1), the appearance of which can be explained by the large defective structure and disorder in the ceria lattice. Copyright (c) 2011 John Wiley and Sons, Ltd.",
journal = "Journal of Raman Spectroscopy",
title = "Oxygen vacancy-induced microstructural changes of annealed CeO2-x nanocrystals",
volume = "43",
number = "1",
pages = "76-81",
doi = "10.1002/jrs.2987"
}

Askrabic, S., Dohcevic-Mitrovic, Z., Kremenović, A. S., Lazarević, N., Kahlenberg, V.,& Popović, Z. V.. (2012). Oxygen vacancy-induced microstructural changes of annealed CeO2-x nanocrystals. in Journal of Raman Spectroscopy, 43(1), 76-81.
https://doi.org/10.1002/jrs.2987

Askrabic S, Dohcevic-Mitrovic Z, Kremenović AS, Lazarević N, Kahlenberg V, Popović ZV. Oxygen vacancy-induced microstructural changes of annealed CeO2-x nanocrystals. in Journal of Raman Spectroscopy. 2012;43(1):76-81.
doi:10.1002/jrs.2987 .

Askrabic, S., Dohcevic-Mitrovic, Z., Kremenović, Aleksandar S., Lazarević, Nataša, Kahlenberg, V., Popović, Zoran V., "Oxygen vacancy-induced microstructural changes of annealed CeO2-x nanocrystals" in Journal of Raman Spectroscopy, 43, no. 1 (2012):76-81,
https://doi.org/10.1002/jrs.2987 . .

TY  - JOUR
AU  - Šćepanović, Maja
AU  - Askrabic, S.
AU  - Grujić-Brojčin, Mirjana
AU  - Golubović, Aleksandar V.
AU  - Dohcevic-Mitrovic, Z.
AU  - Matović, Branko
AU  - Popović, Zoran V.
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6863
AB  - Pure titania (TiO(2)) nanopowders and TiO(2) doped with 10 mol % of vanadium ions (V(3+)) are synthesized by sol-gel method. The dependence of structural characteristics of nanopowders on synthesis conditions is investigated by X-ray diffraction and Raman spectroscopy. Very intensive modes observed in Raman spectra of all nanopowders are assigned to anatase phase of TiO(2). Additional Raman modes of extremely low intensity which can be related to the presence of small
T2  - International Journal of Modern Physics B
T1  - Raman Study of Vanadium-Doped Titania Nanopowders Synthesized By Sol-Gel Method
VL  - 24
IS  - 6-7
SP  - 667
EP  - 675
DO  - 10.1142/S0217979210064289
ER  - 

@article{
author = "Šćepanović, Maja and Askrabic, S. and Grujić-Brojčin, Mirjana and Golubović, Aleksandar V. and Dohcevic-Mitrovic, Z. and Matović, Branko and Popović, Zoran V.",
year = "2010",
abstract = "Pure titania (TiO(2)) nanopowders and TiO(2) doped with 10 mol % of vanadium ions (V(3+)) are synthesized by sol-gel method. The dependence of structural characteristics of nanopowders on synthesis conditions is investigated by X-ray diffraction and Raman spectroscopy. Very intensive modes observed in Raman spectra of all nanopowders are assigned to anatase phase of TiO(2). Additional Raman modes of extremely low intensity which can be related to the presence of small",
journal = "International Journal of Modern Physics B",
title = "Raman Study of Vanadium-Doped Titania Nanopowders Synthesized By Sol-Gel Method",
volume = "24",
number = "6-7",
pages = "667-675",
doi = "10.1142/S0217979210064289"
}

Šćepanović, M., Askrabic, S., Grujić-Brojčin, M., Golubović, A. V., Dohcevic-Mitrovic, Z., Matović, B.,& Popović, Z. V.. (2010). Raman Study of Vanadium-Doped Titania Nanopowders Synthesized By Sol-Gel Method. in International Journal of Modern Physics B, 24(6-7), 667-675.
https://doi.org/10.1142/S0217979210064289

Šćepanović M, Askrabic S, Grujić-Brojčin M, Golubović AV, Dohcevic-Mitrovic Z, Matović B, Popović ZV. Raman Study of Vanadium-Doped Titania Nanopowders Synthesized By Sol-Gel Method. in International Journal of Modern Physics B. 2010;24(6-7):667-675.
doi:10.1142/S0217979210064289 .

Šćepanović, Maja, Askrabic, S., Grujić-Brojčin, Mirjana, Golubović, Aleksandar V., Dohcevic-Mitrovic, Z., Matović, Branko, Popović, Zoran V., "Raman Study of Vanadium-Doped Titania Nanopowders Synthesized By Sol-Gel Method" in International Journal of Modern Physics B, 24, no. 6-7 (2010):667-675,
https://doi.org/10.1142/S0217979210064289 . .