Nikolić, Violeta N.

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  • Nikolić, Violeta N. (14)

Author's Bibliography

The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method

Nikolić, Violeta N.; Vasić, Milica; Milikić, Jadranka; Mariano, Jose F.M.L.

(2021)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Vasić, Milica
AU  - Milikić, Jadranka
AU  - Mariano, Jose F.M.L.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9131
AB  - Abstract: The nanocomposite samples, containing copper and iron species in the silica matrix, were prepared by annealing at temperatures up to 1100°C. The samples were investigated by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and cyclic voltammetry. The results of the performed study depict to the presence of a temperature gradient, which acts on the sample during the annealing treatment in the furnace. For the first time, the influence of the temperature gradient on the formation mechanism of the samples was discussed. © 2021, Pleiades Publishing, Ltd.
T2  - Physics of the Solid State
T1  - The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method
VL  - 63
IS  - 2
SP  - 332
EP  - 354
DO  - 10.1134/S1063783421020207
ER  - 
@article{
author = "Nikolić, Violeta N. and Vasić, Milica and Milikić, Jadranka and Mariano, Jose F.M.L.",
year = "2021",
url = "https://vinar.vin.bg.ac.rs/handle/123456789/9131",
abstract = "Abstract: The nanocomposite samples, containing copper and iron species in the silica matrix, were prepared by annealing at temperatures up to 1100°C. The samples were investigated by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and cyclic voltammetry. The results of the performed study depict to the presence of a temperature gradient, which acts on the sample during the annealing treatment in the furnace. For the first time, the influence of the temperature gradient on the formation mechanism of the samples was discussed. © 2021, Pleiades Publishing, Ltd.",
journal = "Physics of the Solid State",
title = "The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method",
volume = "63",
number = "2",
pages = "332-354",
doi = "10.1134/S1063783421020207"
}
Nikolić, V. N., Vasić, M., Milikić, J.,& Mariano, J. F.M.L. (2021). The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method.
Physics of the Solid State, 63(2), 332-354.
https://doi.org/10.1134/S1063783421020207
Nikolić VN, Vasić M, Milikić J, Mariano JF. The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method. Physics of the Solid State. 2021;63(2):332-354
Nikolić Violeta N., Vasić Milica, Milikić Jadranka, Mariano Jose F.M.L., "The Influence of Thermal Treatment on the Formation Mechanism of the Cu, Fe-Containing Nanocomposite Material Synthesized by the Sol–Gel Method" Physics of the Solid State, 63, no. 2 (2021):332-354,
https://doi.org/10.1134/S1063783421020207 .

Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3

Nikolić, Violeta N.; Milić, Mirjana M.; Zdravković, Jelena D.; Spasojević, Vojislav

(2019)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Milić, Mirjana M.
AU  - Zdravković, Jelena D.
AU  - Spasojević, Vojislav
PY  - 2019
UR  - http://link.springer.com/10.1134/S0036024419030130
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8213
AB  - Abstract: Origin of the intrinsic coercivity field variations observed by hysteretic measurements established by Nikolic et al. was investigated in detail by ZFC/FC measurements. In this study, magnetic behavior of the samples is further examined by calculation of the ZFC Mn(T) and Mn(H) first derivatives. Performed study showed that the main contribution to the measured coercivity comes from the ε-Fe2O3 particles, characterized by Hci = 24 kOe, although both samples posses SPM ε-Fe2O3 fraction. As a result, Hci values of the samples are differed dependent on the quantity of the SPM ε-Fe2O3 particles in the sample. Mechanism of the intrisic coercivity field variations is discussed. © 2019, Pleiades Publishing, Ltd.
T2  - Russian Journal of Physical Chemistry A
T1  - Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3
VL  - 93
IS  - 3
SP  - 588
EP  - 593
DO  - 10.1134/S0036024419030130
ER  - 
@article{
author = "Nikolić, Violeta N. and Milić, Mirjana M. and Zdravković, Jelena D. and Spasojević, Vojislav",
year = "2019",
url = "http://link.springer.com/10.1134/S0036024419030130, http://vinar.vin.bg.ac.rs/handle/123456789/8213",
abstract = "Abstract: Origin of the intrinsic coercivity field variations observed by hysteretic measurements established by Nikolic et al. was investigated in detail by ZFC/FC measurements. In this study, magnetic behavior of the samples is further examined by calculation of the ZFC Mn(T) and Mn(H) first derivatives. Performed study showed that the main contribution to the measured coercivity comes from the ε-Fe2O3 particles, characterized by Hci = 24 kOe, although both samples posses SPM ε-Fe2O3 fraction. As a result, Hci values of the samples are differed dependent on the quantity of the SPM ε-Fe2O3 particles in the sample. Mechanism of the intrisic coercivity field variations is discussed. © 2019, Pleiades Publishing, Ltd.",
journal = "Russian Journal of Physical Chemistry A",
title = "Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3",
volume = "93",
number = "3",
pages = "588-593",
doi = "10.1134/S0036024419030130"
}
Nikolić, V. N., Milić, M. M., Zdravković, J. D.,& Spasojević, V. (2019). Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3.
Russian Journal of Physical Chemistry A, 93(3), 588-593.
https://doi.org/10.1134/S0036024419030130
Nikolić VN, Milić MM, Zdravković JD, Spasojević V. Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3. Russian Journal of Physical Chemistry A. 2019;93(3):588-593
Nikolić Violeta N., Milić Mirjana M., Zdravković Jelena D., Spasojević Vojislav, "Origin of the Intrinsic Coercivity Field Variations and Magnetic Study of ε-Fe2O3" Russian Journal of Physical Chemistry A, 93, no. 3 (2019):588-593,
https://doi.org/10.1134/S0036024419030130 .
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Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3

Nikolić, Violeta N.; Milić, Mirjana M.; Zdravković, Jelena D.; Spasojević, Vojislav

(2019)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Milić, Mirjana M.
AU  - Zdravković, Jelena D.
AU  - Spasojević, Vojislav
PY  - 2019
UR  - http://link.springer.com/10.1134/S0036024419020316
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8214
AB  - Abstract: ε-Fe2O3 phase is recognized as an attractive material, in both technological and scientific point of view, since it can achieve very high room-temperature coercivity (10–20 kOe). In this paper, multi-phase samples Fe2O3/SiO2 with slightly different Fe/Si molar ratio were produced by sol–gel synthesis route. The obtained samples were characterized by various experimental techniques including XRD, TA, FTIR, and SQUID (DC and AC magnetic measurements). It was found that both samples consisted of α-Fe2O3 and ε‑Fe2O3 phases embedded in the silica matrix, and showed very similar structural and magnetic properties, except that displayed significantly different room-temperature intrinsic coercivity field values: HciS1 = 14.3 kOe and HciS2 = 7.5 kOe. We have discussed possible origin of thus high intrinsic coercivity field variation. © 2019, Pleiades Publishing, Ltd.
T2  - Russian Journal of Physical Chemistry A
T1  - Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3
VL  - 93
IS  - 2
SP  - 377
EP  - 383
DO  - 10.1134/S0036024419020316
ER  - 
@article{
author = "Nikolić, Violeta N. and Milić, Mirjana M. and Zdravković, Jelena D. and Spasojević, Vojislav",
year = "2019",
url = "http://link.springer.com/10.1134/S0036024419020316, http://vinar.vin.bg.ac.rs/handle/123456789/8214",
abstract = "Abstract: ε-Fe2O3 phase is recognized as an attractive material, in both technological and scientific point of view, since it can achieve very high room-temperature coercivity (10–20 kOe). In this paper, multi-phase samples Fe2O3/SiO2 with slightly different Fe/Si molar ratio were produced by sol–gel synthesis route. The obtained samples were characterized by various experimental techniques including XRD, TA, FTIR, and SQUID (DC and AC magnetic measurements). It was found that both samples consisted of α-Fe2O3 and ε‑Fe2O3 phases embedded in the silica matrix, and showed very similar structural and magnetic properties, except that displayed significantly different room-temperature intrinsic coercivity field values: HciS1 = 14.3 kOe and HciS2 = 7.5 kOe. We have discussed possible origin of thus high intrinsic coercivity field variation. © 2019, Pleiades Publishing, Ltd.",
journal = "Russian Journal of Physical Chemistry A",
title = "Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3",
volume = "93",
number = "2",
pages = "377-383",
doi = "10.1134/S0036024419020316"
}
Nikolić, V. N., Milić, M. M., Zdravković, J. D.,& Spasojević, V. (2019). Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3.
Russian Journal of Physical Chemistry A, 93(2), 377-383.
https://doi.org/10.1134/S0036024419020316
Nikolić VN, Milić MM, Zdravković JD, Spasojević V. Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3. Russian Journal of Physical Chemistry A. 2019;93(2):377-383
Nikolić Violeta N., Milić Mirjana M., Zdravković Jelena D., Spasojević Vojislav, "Origin of the Intrinsic Coercivity Field Variations of ε-Fe2O3" Russian Journal of Physical Chemistry A, 93, no. 2 (2019):377-383,
https://doi.org/10.1134/S0036024419020316 .
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Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations

Nikolić, Violeta N.; Vasić, Milica M.; Kisić, Danilo

(2019)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Vasić, Milica M.
AU  - Kisić, Danilo
PY  - 2019
UR  - https://linkinghub.elsevier.com/retrieve/pii/S002245961930177X
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8160
AB  - Two samples containing 2-line ferrihydrite and copper oxide were synthesized by coprecipitation method, via variation of Fe3+ and Cu2+ precursors milimolar ratio (3:1 and 3:3.1), while the other synthesis parameters were kept constant. Annealing treatment at 1100 °C resulted in the formation of c-CuFe2O4-CuO-α-Fe2O3 and c-CuFe2O4-CuO nanocomposites, respectively. A comparison of properties of the prepared samples was performed by XRD, FTIR and EPR measurements. Formation mechanism of the nanocomposites is discussed with a reference to the influence of Jahn-Teller effect in CuO phase on the final CuFe2O4 structure. For the first time, it is shown that the amount of Fe3+ precursor is of key importance for the size of CuFe2O4 nanoparticles, and enables preparation of c-CuFe2O4 nanoparticles of the same crystallite size (46 nm) in different nanocomposite materials. © 2019 Elsevier Inc.
T2  - Journal of Solid State Chemistry
T1  - Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations
VL  - 275
SP  - 187
EP  - 196
DO  - 10.1016/j.jssc.2019.04.007
ER  - 
@article{
author = "Nikolić, Violeta N. and Vasić, Milica M. and Kisić, Danilo",
year = "2019",
url = "https://linkinghub.elsevier.com/retrieve/pii/S002245961930177X, http://vinar.vin.bg.ac.rs/handle/123456789/8160",
abstract = "Two samples containing 2-line ferrihydrite and copper oxide were synthesized by coprecipitation method, via variation of Fe3+ and Cu2+ precursors milimolar ratio (3:1 and 3:3.1), while the other synthesis parameters were kept constant. Annealing treatment at 1100 °C resulted in the formation of c-CuFe2O4-CuO-α-Fe2O3 and c-CuFe2O4-CuO nanocomposites, respectively. A comparison of properties of the prepared samples was performed by XRD, FTIR and EPR measurements. Formation mechanism of the nanocomposites is discussed with a reference to the influence of Jahn-Teller effect in CuO phase on the final CuFe2O4 structure. For the first time, it is shown that the amount of Fe3+ precursor is of key importance for the size of CuFe2O4 nanoparticles, and enables preparation of c-CuFe2O4 nanoparticles of the same crystallite size (46 nm) in different nanocomposite materials. © 2019 Elsevier Inc.",
journal = "Journal of Solid State Chemistry",
title = "Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations",
volume = "275",
pages = "187-196",
doi = "10.1016/j.jssc.2019.04.007"
}
Nikolić, V. N., Vasić, M. M.,& Kisić, D. (2019). Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations.
Journal of Solid State Chemistry, 275, 187-196.
https://doi.org/10.1016/j.jssc.2019.04.007
Nikolić VN, Vasić MM, Kisić D. Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations. Journal of Solid State Chemistry. 2019;275:187-196
Nikolić Violeta N., Vasić Milica M., Kisić Danilo, "Observation of c-CuFe2O4 nanoparticles of the same crystallite size in different nanocomposite materials: The influence of Fe3+ cations" Journal of Solid State Chemistry, 275 (2019):187-196,
https://doi.org/10.1016/j.jssc.2019.04.007 .
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Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry

Nikolić, Violeta N.; Tadić, Marin; Jovanović, Sonja; Spasojević, Vojislav

(2019)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Tadić, Marin
AU  - Jovanović, Sonja
AU  - Spasojević, Vojislav
PY  - 2019
UR  - https://linkinghub.elsevier.com/retrieve/pii/S0272884219314166
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8220
AB  - We performed structural and magnetic investigation of Fe3O4/OA nanoparticles prepared by solvothermal method. Based on XRD, TEM and FTIR examination, investigated sample contained monodisperse, 5 nm-sized spherical magnetite nanoparticles coated with oleic acid. Magnetic measurement of the hysteretic curves at 5 K in zero-field cooled (ZFC) and field-cooled (FC) regime confirmed presence of exchange bias effect. ZFC/FC measurements were performed in applied magnetic fields: 10 Oe, 100 Oe, 200 Oe, 500 Oe and 1000 Oe. Zero-field cooled magnetization curves recorded in 10 Oe and 100 Oe exhibited behavior characteristic for low coercivity Nanomaterials. Same sample exposed to the ZFC/FC measurement protocol in 200 Oe, 500 Oe and 1000 Oe showed increase in ZFC magnetization in the certain temperature range. The observed feature is attributed to the local changes in the magnetite electronic structure, occurred through the spin reorientation process. © 2019 Elsevier Ltd and Techna Group S.r.l.
T2  - Ceramics International
T1  - Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry
VL  - 45
IS  - 14
SP  - 17429
EP  - 17437
DO  - 10.1016/j.ceramint.2019.05.303
ER  - 
@article{
author = "Nikolić, Violeta N. and Tadić, Marin and Jovanović, Sonja and Spasojević, Vojislav",
year = "2019",
url = "https://linkinghub.elsevier.com/retrieve/pii/S0272884219314166, http://vinar.vin.bg.ac.rs/handle/123456789/8220",
abstract = "We performed structural and magnetic investigation of Fe3O4/OA nanoparticles prepared by solvothermal method. Based on XRD, TEM and FTIR examination, investigated sample contained monodisperse, 5 nm-sized spherical magnetite nanoparticles coated with oleic acid. Magnetic measurement of the hysteretic curves at 5 K in zero-field cooled (ZFC) and field-cooled (FC) regime confirmed presence of exchange bias effect. ZFC/FC measurements were performed in applied magnetic fields: 10 Oe, 100 Oe, 200 Oe, 500 Oe and 1000 Oe. Zero-field cooled magnetization curves recorded in 10 Oe and 100 Oe exhibited behavior characteristic for low coercivity Nanomaterials. Same sample exposed to the ZFC/FC measurement protocol in 200 Oe, 500 Oe and 1000 Oe showed increase in ZFC magnetization in the certain temperature range. The observed feature is attributed to the local changes in the magnetite electronic structure, occurred through the spin reorientation process. © 2019 Elsevier Ltd and Techna Group S.r.l.",
journal = "Ceramics International",
title = "Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry",
volume = "45",
number = "14",
pages = "17429-17437",
doi = "10.1016/j.ceramint.2019.05.303"
}
Nikolić, V. N., Tadić, M., Jovanović, S.,& Spasojević, V. (2019). Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry.
Ceramics International, 45(14), 17429-17437.
https://doi.org/10.1016/j.ceramint.2019.05.303
Nikolić VN, Tadić M, Jovanović S, Spasojević V. Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry. Ceramics International. 2019;45(14):17429-17437
Nikolić Violeta N., Tadić Marin, Jovanović Sonja, Spasojević Vojislav, "Tracking of the electronic re-ordering in Fe3O4/OA nanoparticles using magnetometry" Ceramics International, 45, no. 14 (2019):17429-17437,
https://doi.org/10.1016/j.ceramint.2019.05.303 .

Unusual temperature dependence of coercivity in ε-Fe2O3 phase

Nikolić, Violeta N.; Tadić, Marin; Mraković, Ana Đ.; Spasojević, Vojislav

(2018)

TY  - CONF
AU  - Nikolić, Violeta N.
AU  - Tadić, Marin
AU  - Mraković, Ana Đ.
AU  - Spasojević, Vojislav
PY  - 2018
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/7850
AB  - Nano iron oxides have been intensively investigated due to their various potential biomedical applications. ε-Fe2O3 phase exerted internal coercivity value up to ~20 kOe, high Curie temperature (Tc= 510 K), and magnetoelectric character. Accordingly, epsilon phase is recognized as a suitable material for medical spintronic biosensors production, that present important part for the lab-on-a-chip systems. Noteworthy, ε-Fe2O3 phase exerts peculiar magnetic behavior. To get better insight into the magnetism of this material, ε-Fe2O3/SiO2 sample was prepared by the combination of the sol-gel synthesis and microemulsion method (Tann=1050 °C, tann= 4h). Afterwards, the sample was exposed to post-annealing treatment at 100 °C and 200 °C. Synthesized material was preliminary examined by XRD and SQUID techniques. Coercivity changes, induced by the post-annealing temperature oscillations, were monitored by hysteretic measurements. Sample annealed at 1050 °C for 4h, showed coercivity ~20 kOe. The same sample performed to the post-annealing treatment at 100 °C, exerted significantly decreased coercivity (~1600 Oe). Further rise of the post-annealing temperature (200 °C) resulted in the increased coercivity ~15 kOe. Obtained study showed that there is insufficient knowledge concerning the ε-Fe2O3 coercivity changes of the polymorph. The more detailed investigation will be conducted, in order to advance the control of the epsilon phase magnetic properties. © 2018 TANGER Ltd. All Rights Reserved.
C3  - NANOCON 2017 - Conference Proceedings, 9th International Conference on Nanomaterials - Research and Application
T1  - Unusual temperature dependence of coercivity in ε-Fe2O3 phase
VL  - 2017-October
SP  - 27
EP  - 32
ER  - 
@conference{
author = "Nikolić, Violeta N. and Tadić, Marin and Mraković, Ana Đ. and Spasojević, Vojislav",
year = "2018",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/7850",
abstract = "Nano iron oxides have been intensively investigated due to their various potential biomedical applications. ε-Fe2O3 phase exerted internal coercivity value up to ~20 kOe, high Curie temperature (Tc= 510 K), and magnetoelectric character. Accordingly, epsilon phase is recognized as a suitable material for medical spintronic biosensors production, that present important part for the lab-on-a-chip systems. Noteworthy, ε-Fe2O3 phase exerts peculiar magnetic behavior. To get better insight into the magnetism of this material, ε-Fe2O3/SiO2 sample was prepared by the combination of the sol-gel synthesis and microemulsion method (Tann=1050 °C, tann= 4h). Afterwards, the sample was exposed to post-annealing treatment at 100 °C and 200 °C. Synthesized material was preliminary examined by XRD and SQUID techniques. Coercivity changes, induced by the post-annealing temperature oscillations, were monitored by hysteretic measurements. Sample annealed at 1050 °C for 4h, showed coercivity ~20 kOe. The same sample performed to the post-annealing treatment at 100 °C, exerted significantly decreased coercivity (~1600 Oe). Further rise of the post-annealing temperature (200 °C) resulted in the increased coercivity ~15 kOe. Obtained study showed that there is insufficient knowledge concerning the ε-Fe2O3 coercivity changes of the polymorph. The more detailed investigation will be conducted, in order to advance the control of the epsilon phase magnetic properties. © 2018 TANGER Ltd. All Rights Reserved.",
journal = "NANOCON 2017 - Conference Proceedings, 9th International Conference on Nanomaterials - Research and Application",
title = "Unusual temperature dependence of coercivity in ε-Fe2O3 phase",
volume = "2017-October",
pages = "27-32"
}
Nikolić, V. N., Tadić, M., Mraković, A. Đ.,& Spasojević, V. (2018). Unusual temperature dependence of coercivity in ε-Fe2O3 phase.
NANOCON 2017 - Conference Proceedings, 9th International Conference on Nanomaterials - Research and Application, 2017-October, 27-32.
Nikolić VN, Tadić M, Mraković AĐ, Spasojević V. Unusual temperature dependence of coercivity in ε-Fe2O3 phase. NANOCON 2017 - Conference Proceedings, 9th International Conference on Nanomaterials - Research and Application. 2018;2017-October:27-32
Nikolić Violeta N., Tadić Marin, Mraković Ana Đ., Spasojević Vojislav, "Unusual temperature dependence of coercivity in ε-Fe2O3 phase" NANOCON 2017 - Conference Proceedings, 9th International Conference on Nanomaterials - Research and Application, 2017-October (2018):27-32

Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation

Nikolić, Violeta N.; Vasić, Milica M.; Milić, Mirjana M.

(2018)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Vasić, Milica M.
AU  - Milić, Mirjana M.
PY  - 2018
UR  - https://linkinghub.elsevier.com/retrieve/pii/S0272884218322168
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/7876
AB  - Samples containing CuFe2O4 and CuO nanoparticles were synthesized by coprecipitation method and subjected to thermal treatment at 300 °C, 500 °C, 700 °C, 900 °C and 1100 °C. Depending on the synthesis conditions, high-temperature treatment of the prepared samples brought to the formation of CuFe2O4 with a tetragonal or cubic structure, which was confirmed by X-ray diffraction analysis. The influence of formation mechanism onto the crystallite sizes of nanoparticles and structural transformation of CuFe2O4 is discussed. For the first time it was shown that variations of the initial amount of Fe3+ and Cu2+ ions precursors resulted in the formation of low- and high-temperature CuFe2O4 phase at the same annealing temperature, 1100 °C. © 2018
T2  - Ceramics International
T1  - Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation
VL  - 44
IS  - 17
SP  - 21145
EP  - 21152
DO  - 10.1016/j.ceramint.2018.08.157
ER  - 
@article{
author = "Nikolić, Violeta N. and Vasić, Milica M. and Milić, Mirjana M.",
year = "2018",
url = "https://linkinghub.elsevier.com/retrieve/pii/S0272884218322168, http://vinar.vin.bg.ac.rs/handle/123456789/7876",
abstract = "Samples containing CuFe2O4 and CuO nanoparticles were synthesized by coprecipitation method and subjected to thermal treatment at 300 °C, 500 °C, 700 °C, 900 °C and 1100 °C. Depending on the synthesis conditions, high-temperature treatment of the prepared samples brought to the formation of CuFe2O4 with a tetragonal or cubic structure, which was confirmed by X-ray diffraction analysis. The influence of formation mechanism onto the crystallite sizes of nanoparticles and structural transformation of CuFe2O4 is discussed. For the first time it was shown that variations of the initial amount of Fe3+ and Cu2+ ions precursors resulted in the formation of low- and high-temperature CuFe2O4 phase at the same annealing temperature, 1100 °C. © 2018",
journal = "Ceramics International",
title = "Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation",
volume = "44",
number = "17",
pages = "21145-21152",
doi = "10.1016/j.ceramint.2018.08.157"
}
Nikolić, V. N., Vasić, M. M.,& Milić, M. M. (2018). Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation.
Ceramics International, 44(17), 21145-21152.
https://doi.org/10.1016/j.ceramint.2018.08.157
Nikolić VN, Vasić MM, Milić MM. Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation. Ceramics International. 2018;44(17):21145-21152
Nikolić Violeta N., Vasić Milica M., Milić Mirjana M., "Observation of low- and high-temperature CuFe2O4 phase at 1100 °C: The influence of Fe3+ ions on CuFe2O4 structural transformation" Ceramics International, 44, no. 17 (2018):21145-21152,
https://doi.org/10.1016/j.ceramint.2018.08.157 .
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Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином

Nikolić, Violeta N.

(Универзитет у Београду, Факултет за физичку хемију, 2017)

TY  - BOOK
AU  - Nikolić, Violeta N.
PY  - 2017
UR  - http://nardus.mpn.gov.rs/handle/123456789/8942
UR  - http://eteze.bg.ac.rs/application/showtheses?thesesId=5410
UR  - https://fedorabg.bg.ac.rs/fedora/get/o:16782/bdef:Content/download
UR  - https://plus.sr.cobiss.net/opac7/bib/49633807
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8980
AB  - У оквиру ове дисертације су представљени резултати проучавања магнетнихособина наночестичних оксида гвожђа површински модификованих силицијумдиоксидом (SiO2) и олеинском киселином (ОК). Узорци су синтетисани применом триразличита поступка: комбинацијом микроемулзије и сол-гел методе, сол-гелпоступком, и солвотермалном синтезом. У зависности од циља испитивања,структурна и магнетна карактеризација узорака је извршена применом рендгенскедифракције, трансмисионе електронске микроскопије, термијске анализе,инфрацрвене спектроскопије са Fourier-овом трансформацијом, као и применоммагнетних мерења. Посебна пажња је посвећена испитивању магнетног понашањасинтетисаних материјала...
AB  - The aim of this thesis was to investigate magetnic properties of the iron oxidenanoparticles, surface-modified with silica and oleic acid. Samples were prepared by usingthree different synthetic approaches: acid catalysed sol-gel synthesis, combination of themicroemulsion and sol-gel method, and solvothermal synthesis. Structural and magneticinvestigation of the synthesized materials was performed by using X-ray diffraction (XRD),transmission electron microscopy (TEM), thermal analysis (TA), Foruier transform IRspectroscopy(FTIR), and SQUID measurement techniques. Special focus was directed toinvestigation of the magnetic behavior of the examined materials...
PB  - Универзитет у Београду, Факултет за физичку хемију
T2  - Универзитет у Београду
T1  - Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином
ER  - 
@phdthesis{
author = "Nikolić, Violeta N.",
year = "2017",
url = "http://nardus.mpn.gov.rs/handle/123456789/8942, http://eteze.bg.ac.rs/application/showtheses?thesesId=5410, https://fedorabg.bg.ac.rs/fedora/get/o:16782/bdef:Content/download, https://plus.sr.cobiss.net/opac7/bib/49633807, https://vinar.vin.bg.ac.rs/handle/123456789/8980",
abstract = "У оквиру ове дисертације су представљени резултати проучавања магнетнихособина наночестичних оксида гвожђа површински модификованих силицијумдиоксидом (SiO2) и олеинском киселином (ОК). Узорци су синтетисани применом триразличита поступка: комбинацијом микроемулзије и сол-гел методе, сол-гелпоступком, и солвотермалном синтезом. У зависности од циља испитивања,структурна и магнетна карактеризација узорака је извршена применом рендгенскедифракције, трансмисионе електронске микроскопије, термијске анализе,инфрацрвене спектроскопије са Fourier-овом трансформацијом, као и применоммагнетних мерења. Посебна пажња је посвећена испитивању магнетног понашањасинтетисаних материјала..., The aim of this thesis was to investigate magetnic properties of the iron oxidenanoparticles, surface-modified with silica and oleic acid. Samples were prepared by usingthree different synthetic approaches: acid catalysed sol-gel synthesis, combination of themicroemulsion and sol-gel method, and solvothermal synthesis. Structural and magneticinvestigation of the synthesized materials was performed by using X-ray diffraction (XRD),transmission electron microscopy (TEM), thermal analysis (TA), Foruier transform IRspectroscopy(FTIR), and SQUID measurement techniques. Special focus was directed toinvestigation of the magnetic behavior of the examined materials...",
publisher = "Универзитет у Београду, Факултет за физичку хемију",
journal = "Универзитет у Београду",
title = "Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином"
}
Nikolić, V. N. (2017). Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином.
Универзитет у Београду
Универзитет у Београду, Факултет за физичку хемију..
Nikolić VN. Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином. Универзитет у Београду. 2017;
Nikolić Violeta N., "Магнетне особине наночестица оксида гвожђа површински модификованих силицијум диоксидом и олеинском киселином" Универзитет у Београду (2017)

Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase

Nikolić, Violeta N.; Tadić, Marin; Panjan, Matjaž; Kopanja, Lazar; Cvjeticanin, Nikola; Spasojević, Vojislav

(2017)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Tadić, Marin
AU  - Panjan, Matjaž
AU  - Kopanja, Lazar
AU  - Cvjeticanin, Nikola
AU  - Spasojević, Vojislav
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1400
AB  - Magnetic properties of Fe2O3/SiO2 samples were studied after being produced by sol-gel synthesis and formation of epsilon-Fe2O3 polymorph. Samples were thermally treated, using different annealing temperatures and annealing times. The size and morphological characteristics of the iron oxide nanoparticles were examined using a TEM microscope. We used the ellipticity of shapes, which is a measure of how much the shape of a nanoparticle differs from a perfect ellipse, in order to quantitatively describe morphological properties of nanoparticles. Coercivity measurements were used to identify and monitor the formation of the epsilon-iron oxide phase during the thermal treatments (annealing). Coercivity values were in the range from 1.2 to 15.4 kOe, which is in accordance with previous experience regarding the existence of epsilon-Fe2O3. We have determined the optimal formation conditions for the epsilon-Fe2O3 polymorph (t=1050 degrees C for 7 h, H-c=15.4 kOe), as well as the narrow temperature interval (1050-1060 C) in which the polymorph abruptly vanished (H-c=2300 Oe), on the basis of results of the magnetic properties. The threshold temperature for the epsilon-Fe2O3 phase transformation was measured as 1060 degrees C. We found that different annealing temperatures and annealing times significantly affected magnetic properties of the examined samples.
T2  - Ceramics International
T1  - Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase
VL  - 43
IS  - 3
SP  - 3147
EP  - 3155
DO  - 10.1016/j.ceramint.2016.11.132
ER  - 
@article{
author = "Nikolić, Violeta N. and Tadić, Marin and Panjan, Matjaž and Kopanja, Lazar and Cvjeticanin, Nikola and Spasojević, Vojislav",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1400",
abstract = "Magnetic properties of Fe2O3/SiO2 samples were studied after being produced by sol-gel synthesis and formation of epsilon-Fe2O3 polymorph. Samples were thermally treated, using different annealing temperatures and annealing times. The size and morphological characteristics of the iron oxide nanoparticles were examined using a TEM microscope. We used the ellipticity of shapes, which is a measure of how much the shape of a nanoparticle differs from a perfect ellipse, in order to quantitatively describe morphological properties of nanoparticles. Coercivity measurements were used to identify and monitor the formation of the epsilon-iron oxide phase during the thermal treatments (annealing). Coercivity values were in the range from 1.2 to 15.4 kOe, which is in accordance with previous experience regarding the existence of epsilon-Fe2O3. We have determined the optimal formation conditions for the epsilon-Fe2O3 polymorph (t=1050 degrees C for 7 h, H-c=15.4 kOe), as well as the narrow temperature interval (1050-1060 C) in which the polymorph abruptly vanished (H-c=2300 Oe), on the basis of results of the magnetic properties. The threshold temperature for the epsilon-Fe2O3 phase transformation was measured as 1060 degrees C. We found that different annealing temperatures and annealing times significantly affected magnetic properties of the examined samples.",
journal = "Ceramics International",
title = "Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase",
volume = "43",
number = "3",
pages = "3147-3155",
doi = "10.1016/j.ceramint.2016.11.132"
}
Nikolić, V. N., Tadić, M., Panjan, M., Kopanja, L., Cvjeticanin, N.,& Spasojević, V. (2017). Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase.
Ceramics International, 43(3), 3147-3155.
https://doi.org/10.1016/j.ceramint.2016.11.132
Nikolić VN, Tadić M, Panjan M, Kopanja L, Cvjeticanin N, Spasojević V. Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase. Ceramics International. 2017;43(3):3147-3155
Nikolić Violeta N., Tadić Marin, Panjan Matjaž, Kopanja Lazar, Cvjeticanin Nikola, Spasojević Vojislav, "Influence of annealing treatment on magnetic properties of Fe2O3/SiO2 and formation of epsilon-Fe2O3 phase" Ceramics International, 43, no. 3 (2017):3147-3155,
https://doi.org/10.1016/j.ceramint.2016.11.132 .
28
25
28

Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties

Nikolić, Violeta N.; Spasojević, Vojislav; Panjan, Matjaž; Kopanja, Lazar; Mraković, Ana Đ.; Tadić, Marin

(2017)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Spasojević, Vojislav
AU  - Panjan, Matjaž
AU  - Kopanja, Lazar
AU  - Mraković, Ana Đ.
AU  - Tadić, Marin
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1559
AB  - Several Fe2O3/SiO2 nanostructures were synthesized by the combination of the microemulsion and a sol-gel methods. Based on X-ray powder diffraction (XRD) and magnetic measurements (giant coercivity similar to 2.13 T) we identified epsilon-Fe2O3 (hard magnet) as the dominant crystalline phase. TEM analysis showed a wide size distribution of iron oxide nanoparticles (from 4 to 50 nm) with various morphologies (spherical, ellipsoidal and rod-like). We quantitatively described (computational analysis, MATLAB code) morphological properties of nanoparticles using the ellipticity of the shapes. The as-synthesized hard magnetic material was subjected to a post-annealing treatment at different temperatures (200, 500, 750, 1000 and 1100 degrees C) in order to investigate stability, formation and transformation of the epsilon-Fe2O3 polymorph. We found decreasing coercivity in the thermally treated samples up to the temperature of 750 degrees C (H-c=1245 Oe), followed by an observation of a surprising jump in coercivity H-c similar to 1.5 T after post-annealing at 1000 degrees C. We conclude that the re-formation of the epsilon-Fe2O3 structure during post-annealing at 1000 degrees C is the origin of the observed phenomena. The phase transformation epsilon-Fe2O3 - GT alpha-Fe2O3 and crystallization of amorphous silica in quartz and cristobalite were observed in the sample treated at 1100 degrees C.
T2  - Ceramics International
T1  - Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties
VL  - 43
IS  - 10
SP  - 7497
EP  - 7507
DO  - 10.1016/j.ceramint.2017.03.030
ER  - 
@article{
author = "Nikolić, Violeta N. and Spasojević, Vojislav and Panjan, Matjaž and Kopanja, Lazar and Mraković, Ana Đ. and Tadić, Marin",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1559",
abstract = "Several Fe2O3/SiO2 nanostructures were synthesized by the combination of the microemulsion and a sol-gel methods. Based on X-ray powder diffraction (XRD) and magnetic measurements (giant coercivity similar to 2.13 T) we identified epsilon-Fe2O3 (hard magnet) as the dominant crystalline phase. TEM analysis showed a wide size distribution of iron oxide nanoparticles (from 4 to 50 nm) with various morphologies (spherical, ellipsoidal and rod-like). We quantitatively described (computational analysis, MATLAB code) morphological properties of nanoparticles using the ellipticity of the shapes. The as-synthesized hard magnetic material was subjected to a post-annealing treatment at different temperatures (200, 500, 750, 1000 and 1100 degrees C) in order to investigate stability, formation and transformation of the epsilon-Fe2O3 polymorph. We found decreasing coercivity in the thermally treated samples up to the temperature of 750 degrees C (H-c=1245 Oe), followed by an observation of a surprising jump in coercivity H-c similar to 1.5 T after post-annealing at 1000 degrees C. We conclude that the re-formation of the epsilon-Fe2O3 structure during post-annealing at 1000 degrees C is the origin of the observed phenomena. The phase transformation epsilon-Fe2O3 - GT alpha-Fe2O3 and crystallization of amorphous silica in quartz and cristobalite were observed in the sample treated at 1100 degrees C.",
journal = "Ceramics International",
title = "Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties",
volume = "43",
number = "10",
pages = "7497-7507",
doi = "10.1016/j.ceramint.2017.03.030"
}
Nikolić, V. N., Spasojević, V., Panjan, M., Kopanja, L., Mraković, A. Đ.,& Tadić, M. (2017). Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties.
Ceramics International, 43(10), 7497-7507.
https://doi.org/10.1016/j.ceramint.2017.03.030
Nikolić VN, Spasojević V, Panjan M, Kopanja L, Mraković AĐ, Tadić M. Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties. Ceramics International. 2017;43(10):7497-7507
Nikolić Violeta N., Spasojević Vojislav, Panjan Matjaž, Kopanja Lazar, Mraković Ana Đ., Tadić Marin, "Re-formation of metastable epsilon-Fe2O3 in post-annealing of Fe2O3/SiO2 nanostructure: Synthesis, computational particle shape analysis in micrographs and magnetic properties" Ceramics International, 43, no. 10 (2017):7497-7507,
https://doi.org/10.1016/j.ceramint.2017.03.030 .
27
23
26

Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3

Šaponjić, Aleksandra; Šaponjić, Đorđe; Nikolić, Violeta N.; Milošević, Maja; Marinović-Cincović, Milena; Gyoshev, Stanislav; Vuković, Marina; Kokunešoski, Maja

(2017)

TY  - JOUR
AU  - Šaponjić, Aleksandra
AU  - Šaponjić, Đorđe
AU  - Nikolić, Violeta N.
AU  - Milošević, Maja
AU  - Marinović-Cincović, Milena
AU  - Gyoshev, Stanislav
AU  - Vuković, Marina
AU  - Kokunešoski, Maja
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1644
AB  - Amorphous iron (III) oxide was obtained from clay, using ammonium hydroxide as a precipitating agent. Influence of freeze drying under vacuum, as a drying method, on particle size, chemical composition, and crystallinity of obtained iron (III) oxide powder was investigated. After freeze drying, precipitate was annealed in air at 500 C-o and 900 oC. X-ray diffraction, particle size analysis, scanning electron microscopy, energy dispersive spectrometry, Fourier transform infrared spectroscopy, thermogravimetric and differential thermal analysis were used to characterize obtained iron (III) oxide powder. All of three powders obtained by freeze drying and annealing, have low crystallinity and particles with irregular layered shape. Narrow particle size distribution was given by an average diameter value of around 50 mu m for all observed powders. Iron-bearing materials like a-Fe2O3 and gamma-Fe2O3 are obtained. Differential thermal analysis curve of obtained samples showed endothermic reaction at 620 oC which could be ascribed to phase transition from cubic form gamma- - GT alpha- Fe2O3. Thermal transformations of iron (III) oxide, obtained from clay as a natural source, is suitable to explore in the framework of materials chemistry, and opens the possibility to synthesize materials based on Fe2O3 with specific magnetic behavior.
T2  - Science of Sintering
T1  - Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3
VL  - 49
IS  - 2
SP  - 197
EP  - 205
DO  - 10.2298/SOS1702197S
ER  - 
@article{
author = "Šaponjić, Aleksandra and Šaponjić, Đorđe and Nikolić, Violeta N. and Milošević, Maja and Marinović-Cincović, Milena and Gyoshev, Stanislav and Vuković, Marina and Kokunešoski, Maja",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1644",
abstract = "Amorphous iron (III) oxide was obtained from clay, using ammonium hydroxide as a precipitating agent. Influence of freeze drying under vacuum, as a drying method, on particle size, chemical composition, and crystallinity of obtained iron (III) oxide powder was investigated. After freeze drying, precipitate was annealed in air at 500 C-o and 900 oC. X-ray diffraction, particle size analysis, scanning electron microscopy, energy dispersive spectrometry, Fourier transform infrared spectroscopy, thermogravimetric and differential thermal analysis were used to characterize obtained iron (III) oxide powder. All of three powders obtained by freeze drying and annealing, have low crystallinity and particles with irregular layered shape. Narrow particle size distribution was given by an average diameter value of around 50 mu m for all observed powders. Iron-bearing materials like a-Fe2O3 and gamma-Fe2O3 are obtained. Differential thermal analysis curve of obtained samples showed endothermic reaction at 620 oC which could be ascribed to phase transition from cubic form gamma- - GT alpha- Fe2O3. Thermal transformations of iron (III) oxide, obtained from clay as a natural source, is suitable to explore in the framework of materials chemistry, and opens the possibility to synthesize materials based on Fe2O3 with specific magnetic behavior.",
journal = "Science of Sintering",
title = "Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3",
volume = "49",
number = "2",
pages = "197-205",
doi = "10.2298/SOS1702197S"
}
Šaponjić, A., Šaponjić, Đ., Nikolić, V. N., Milošević, M., Marinović-Cincović, M., Gyoshev, S., Vuković, M.,& Kokunešoski, M. (2017). Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3.
Science of Sintering, 49(2), 197-205.
https://doi.org/10.2298/SOS1702197S
Šaponjić A, Šaponjić Đ, Nikolić VN, Milošević M, Marinović-Cincović M, Gyoshev S, Vuković M, Kokunešoski M. Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3. Science of Sintering. 2017;49(2):197-205
Šaponjić Aleksandra, Šaponjić Đorđe, Nikolić Violeta N., Milošević Maja, Marinović-Cincović Milena, Gyoshev Stanislav, Vuković Marina, Kokunešoski Maja, "Iron (III) Oxide Fabrication From Natural Clay With Reference to Phase Transformation gamma- - GT alpha- Fe2O3" Science of Sintering, 49, no. 2 (2017):197-205,
https://doi.org/10.2298/SOS1702197S .
1
1

Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder

Milić, Mirjana M.; Nikolić, Violeta N.; Jovanović, Sonja

(2017)

TY  - JOUR
AU  - Milić, Mirjana M.
AU  - Nikolić, Violeta N.
AU  - Jovanović, Sonja
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1735
AB  - In this work, sol gel method was used to prepare FexOy/Gd2O3/SiO2 composite system starting from two different iron precursors: iron nitrate and iron oxide xerogel. The obtained samples were subjected to heat treatment at different temperatures under atmospheric conditions. Thermal evolution of the prepared samples has been systematically investigated by using X-ray diffraction (XRD) analysis and Fourier transform infrared spectroscopy (FTIR). Samples calcined at 1030 degrees C were also characterized by transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) experimental techniques. Effect of thermal treatment on phase formation in the prepared composite system has been discussed. It was found that iron nitrate based sample developed only alpha-Fe2O3 structural phase, while the sample based on the iron oxide xerogel developed alpha-Fe2O3 and gamma-Fe2O3 phases, with both of them remaining stable up to temperatures as high as 1030 degrees C. Gadolinium precursor crystallized directly in low-temperature triclinic B-type gadolinium disilicate Gd2Si2O7 (Gd2O3 center dot 2SiO(2)) phase at 900 degrees C, without formation of intermediate monosilicate phase. No other crystalline phases related to gadolinium were observed.
T2  - Ceramics International
T1  - Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder
VL  - 43
IS  - 16
SP  - 14044
EP  - 14049
DO  - 10.1016/j.ceramint.2017.07.138
ER  - 
@article{
author = "Milić, Mirjana M. and Nikolić, Violeta N. and Jovanović, Sonja",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1735",
abstract = "In this work, sol gel method was used to prepare FexOy/Gd2O3/SiO2 composite system starting from two different iron precursors: iron nitrate and iron oxide xerogel. The obtained samples were subjected to heat treatment at different temperatures under atmospheric conditions. Thermal evolution of the prepared samples has been systematically investigated by using X-ray diffraction (XRD) analysis and Fourier transform infrared spectroscopy (FTIR). Samples calcined at 1030 degrees C were also characterized by transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) experimental techniques. Effect of thermal treatment on phase formation in the prepared composite system has been discussed. It was found that iron nitrate based sample developed only alpha-Fe2O3 structural phase, while the sample based on the iron oxide xerogel developed alpha-Fe2O3 and gamma-Fe2O3 phases, with both of them remaining stable up to temperatures as high as 1030 degrees C. Gadolinium precursor crystallized directly in low-temperature triclinic B-type gadolinium disilicate Gd2Si2O7 (Gd2O3 center dot 2SiO(2)) phase at 900 degrees C, without formation of intermediate monosilicate phase. No other crystalline phases related to gadolinium were observed.",
journal = "Ceramics International",
title = "Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder",
volume = "43",
number = "16",
pages = "14044-14049",
doi = "10.1016/j.ceramint.2017.07.138"
}
Milić, M. M., Nikolić, V. N.,& Jovanović, S. (2017). Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder.
Ceramics International, 43(16), 14044-14049.
https://doi.org/10.1016/j.ceramint.2017.07.138
Milić MM, Nikolić VN, Jovanović S. Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder. Ceramics International. 2017;43(16):14044-14049
Milić Mirjana M., Nikolić Violeta N., Jovanović Sonja, "Synthesis and characterization of nanocrystalline FexOy/Gd2O3/SiO2 composite powder" Ceramics International, 43, no. 16 (2017):14044-14049,
https://doi.org/10.1016/j.ceramint.2017.07.138 .
3
1
2

The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate

Perović, Marija M.; Kusigerski, Vladan; Mraković, Ana Đ.; Spasojević, Vojislav; Blanuša, Jovan; Nikolić, Violeta N.; Schneeweiss, O.; David, B.; Pizurova, N.

(2015)

TY  - JOUR
AU  - Perović, Marija M.
AU  - Kusigerski, Vladan
AU  - Mraković, Ana Đ.
AU  - Spasojević, Vojislav
AU  - Blanuša, Jovan
AU  - Nikolić, Violeta N.
AU  - Schneeweiss, O.
AU  - David, B.
AU  - Pizurova, N.
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/429
AB  - Nanorod ferrous oxalate dihydrate (FeC2O4 x 2H(2)O) which had been synthesized by the microemulsion method, was used as a precursor in the thermal decomposition process performed in air atmosphere. The formation of nanocrystalline hematite as the final product was preceded by the appearence of an intermediate product. Comprehensive study comprising several complementary techniques (x-ray diffraction, transmission electron microscopy, selected area electron diffraction, thermogravimetric/differential thermal analyses and SQUID magnetometry) confirmed that the intermediate product corresponds to the poorly crystalline Fe2O3. Due to the specific nanorod shape and poorly crystalline structure, the investigated Fe2O3 showed high coercive field value of similar to 0.5 T at 5 K. Special attention in this study was devoted to the peculiar magnetic properties of poorly crystalline Fe2O3, which were thoroughly investigated by employing sophisticated experimental procedures such as relaxation of thermoremanent magnetization for different cooling fields, zero field and field cooled memory effects as well as aging experiments for different waiting times. At low temperatures and weak applied magnetic fields, the investigated system behaves similarly to spin glasses, manifesting slow, collective relaxation dynamics of magnetic moments through memory, rejuvenation and aging effects.
T2  - Nanotechnology
T1  - The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate
VL  - 26
IS  - 11
DO  - 10.1088/0957-4484/26/11/115705
ER  - 
@article{
author = "Perović, Marija M. and Kusigerski, Vladan and Mraković, Ana Đ. and Spasojević, Vojislav and Blanuša, Jovan and Nikolić, Violeta N. and Schneeweiss, O. and David, B. and Pizurova, N.",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/429",
abstract = "Nanorod ferrous oxalate dihydrate (FeC2O4 x 2H(2)O) which had been synthesized by the microemulsion method, was used as a precursor in the thermal decomposition process performed in air atmosphere. The formation of nanocrystalline hematite as the final product was preceded by the appearence of an intermediate product. Comprehensive study comprising several complementary techniques (x-ray diffraction, transmission electron microscopy, selected area electron diffraction, thermogravimetric/differential thermal analyses and SQUID magnetometry) confirmed that the intermediate product corresponds to the poorly crystalline Fe2O3. Due to the specific nanorod shape and poorly crystalline structure, the investigated Fe2O3 showed high coercive field value of similar to 0.5 T at 5 K. Special attention in this study was devoted to the peculiar magnetic properties of poorly crystalline Fe2O3, which were thoroughly investigated by employing sophisticated experimental procedures such as relaxation of thermoremanent magnetization for different cooling fields, zero field and field cooled memory effects as well as aging experiments for different waiting times. At low temperatures and weak applied magnetic fields, the investigated system behaves similarly to spin glasses, manifesting slow, collective relaxation dynamics of magnetic moments through memory, rejuvenation and aging effects.",
journal = "Nanotechnology",
title = "The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate",
volume = "26",
number = "11",
doi = "10.1088/0957-4484/26/11/115705"
}
Perović, M. M., Kusigerski, V., Mraković, A. Đ., Spasojević, V., Blanuša, J., Nikolić, V. N., Schneeweiss, O., David, B.,& Pizurova, N. (2015). The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate.
Nanotechnology, 26(11).
https://doi.org/10.1088/0957-4484/26/11/115705
Perović MM, Kusigerski V, Mraković AĐ, Spasojević V, Blanuša J, Nikolić VN, Schneeweiss O, David B, Pizurova N. The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate. Nanotechnology. 2015;26(11)
Perović Marija M., Kusigerski Vladan, Mraković Ana Đ., Spasojević Vojislav, Blanuša Jovan, Nikolić Violeta N., Schneeweiss O., David B., Pizurova N., "The glassy behaviour of poorly crystalline Fe2O3 nanorods obtained by thermal decomposition of ferrous oxalate" Nanotechnology, 26, no. 11 (2015),
https://doi.org/10.1088/0957-4484/26/11/115705 .
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Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system

Nikolić, Violeta N.; Perović, Marija M.; Kusigerski, Vladan; Bošković, Marko; Mraković, Ana Đ.; Blanuša, Jovan; Spasojević, Vojislav

(2015)

TY  - JOUR
AU  - Nikolić, Violeta N.
AU  - Perović, Marija M.
AU  - Kusigerski, Vladan
AU  - Bošković, Marko
AU  - Mraković, Ana Đ.
AU  - Blanuša, Jovan
AU  - Spasojević, Vojislav
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/561
AB  - Spherical gamma-Fe2O3 nanoparticles with the narrow size distribution of (5 +/- 1) nm were synthesized by the method of thermal decomposition from iron acetyl acetonate precursor. The existence of super spin-glass state at low temperatures and in low applied magnetic fields was confirmed by DC magnetization measurements on a SQUID magnetometer. The comprehensive investigation of magnetic relaxation dynamics in low-temperature region was conducted through the measurements of single-stop and multiple stop ZFC memory effects, ZFC magnetization relaxation, and AC susceptibility measurements. The experimental findings revealed the peculiar change of magnetic relaxation dynamics at T approximate to 10 K, which arose as a consequence of simultaneous existence of different relaxation processes in Fe2O3 nanoparticle system. Complementarity of the applied measurements was utilized in order to single out distinct relaxation processes as well as to elucidate complex relaxation mechanisms in the investigated interacting nanoparticle system.
T2  - Journal of Nanoparticle Research
T1  - Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system
VL  - 17
IS  - 3
DO  - 10.1007/s11051-015-2952-2
ER  - 
@article{
author = "Nikolić, Violeta N. and Perović, Marija M. and Kusigerski, Vladan and Bošković, Marko and Mraković, Ana Đ. and Blanuša, Jovan and Spasojević, Vojislav",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/561",
abstract = "Spherical gamma-Fe2O3 nanoparticles with the narrow size distribution of (5 +/- 1) nm were synthesized by the method of thermal decomposition from iron acetyl acetonate precursor. The existence of super spin-glass state at low temperatures and in low applied magnetic fields was confirmed by DC magnetization measurements on a SQUID magnetometer. The comprehensive investigation of magnetic relaxation dynamics in low-temperature region was conducted through the measurements of single-stop and multiple stop ZFC memory effects, ZFC magnetization relaxation, and AC susceptibility measurements. The experimental findings revealed the peculiar change of magnetic relaxation dynamics at T approximate to 10 K, which arose as a consequence of simultaneous existence of different relaxation processes in Fe2O3 nanoparticle system. Complementarity of the applied measurements was utilized in order to single out distinct relaxation processes as well as to elucidate complex relaxation mechanisms in the investigated interacting nanoparticle system.",
journal = "Journal of Nanoparticle Research",
title = "Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system",
volume = "17",
number = "3",
doi = "10.1007/s11051-015-2952-2"
}
Nikolić, V. N., Perović, M. M., Kusigerski, V., Bošković, M., Mraković, A. Đ., Blanuša, J.,& Spasojević, V. (2015). Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system.
Journal of Nanoparticle Research, 17(3).
https://doi.org/10.1007/s11051-015-2952-2
Nikolić VN, Perović MM, Kusigerski V, Bošković M, Mraković AĐ, Blanuša J, Spasojević V. Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system. Journal of Nanoparticle Research. 2015;17(3)
Nikolić Violeta N., Perović Marija M., Kusigerski Vladan, Bošković Marko, Mraković Ana Đ., Blanuša Jovan, Spasojević Vojislav, "Experimental evidence for simultaneous relaxation processes in super spin glass gamma-Fe2O3 nanoparticle system" Journal of Nanoparticle Research, 17, no. 3 (2015),
https://doi.org/10.1007/s11051-015-2952-2 .
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