TY  - JOUR
AU  - Paunović, Vesna
AU  - Mitić, Vojislav V.
AU  - Đorđević, M.
AU  - Prijić, Z.
PY  - 2020
UR  - http://www.sciencedirect.com/science/article/pii/S0272884219335205
UR  - https://dais.sanu.ac.rs/123456789/8964
AB  - The effect of Nb on the microstructure and dielectric properties of BaTiO3 ceramics was investigated. The Nb/Mn–BaTiO3 ceramics were prepared using a conventional solid-state method. The concentration of Nb varied from 0.1 to 5.0 at% but Mn was fixed at 0.05 at%. The SEM indicated that compositions of 0.1 and 0.5 at% Nb displayed a fairly uniform microstructure and homogeneous distribution of additives, with a grain size of less than 2 μm. In highly doped samples a wide range of microstructural features was observed, from homogeneous and completely fine-grained microstructure to the appearance of secondary abnormal grains with core-shell structure. The dielectric constant and the loss tangent of modified ceramics were measured as a function of temperature (20–180 °C) and frequency (100 Hz-1MHz) for different concentrations of additives. The obtained results have shown that the dielectric constant at, both, room temperature (εr) and Curie temperature (εrmax), decreased as the concentration of Nb5+ increased. Thus, the highest values for the dielectric constant at room temperature (εr = 6648) as well as at Curie temperature (εrmax = 7680) were measured for the 0.1Nb/Mn–BaTiO3 samples sintered at 1350 °C. The highly doped BaTiO3 ceramics were found to exhibit lower values of the dielectric constant and low dielectric losses at room temperature. In these samples, stable dielectric permittivity with a flat dielectric behavior over a wide temperature range is observed. The Curie constant for all series of samples decreases with an increase of dopant concentration and the highest values were measured from samples doped with 0.1 at% Nb. The effect of additives on the Curie constant change is more pronounced at higher sintering temperatures. The analysis of the critical nonlinearity exponent (γ = 1.07–1.27), for lower dopant concentrations, shows a sharp phase transformation. For samples with increased Nb content, the degree of nonlinearity γ is higher indicating a diffuse phase transformation.
PB  - Elsevier
T2  - Ceramics International
T1  - Niobium doping effect on BaTiO3 structure and dielectric properties
SP  - 8154
EP  - 8164
VL  - 46
IS  - 6
DO  - 10.1016/j.ceramint.2019.12.043
UR  - https://hdl.handle.net/21.15107/rcub_dais_8964
ER  - 

@article{
author = "Paunović, Vesna and Mitić, Vojislav V. and Đorđević, M. and Prijić, Z.",
year = "2020",
abstract = "The effect of Nb on the microstructure and dielectric properties of BaTiO3 ceramics was investigated. The Nb/Mn–BaTiO3 ceramics were prepared using a conventional solid-state method. The concentration of Nb varied from 0.1 to 5.0 at% but Mn was fixed at 0.05 at%. The SEM indicated that compositions of 0.1 and 0.5 at% Nb displayed a fairly uniform microstructure and homogeneous distribution of additives, with a grain size of less than 2 μm. In highly doped samples a wide range of microstructural features was observed, from homogeneous and completely fine-grained microstructure to the appearance of secondary abnormal grains with core-shell structure. The dielectric constant and the loss tangent of modified ceramics were measured as a function of temperature (20–180 °C) and frequency (100 Hz-1MHz) for different concentrations of additives. The obtained results have shown that the dielectric constant at, both, room temperature (εr) and Curie temperature (εrmax), decreased as the concentration of Nb5+ increased. Thus, the highest values for the dielectric constant at room temperature (εr = 6648) as well as at Curie temperature (εrmax = 7680) were measured for the 0.1Nb/Mn–BaTiO3 samples sintered at 1350 °C. The highly doped BaTiO3 ceramics were found to exhibit lower values of the dielectric constant and low dielectric losses at room temperature. In these samples, stable dielectric permittivity with a flat dielectric behavior over a wide temperature range is observed. The Curie constant for all series of samples decreases with an increase of dopant concentration and the highest values were measured from samples doped with 0.1 at% Nb. The effect of additives on the Curie constant change is more pronounced at higher sintering temperatures. The analysis of the critical nonlinearity exponent (γ = 1.07–1.27), for lower dopant concentrations, shows a sharp phase transformation. For samples with increased Nb content, the degree of nonlinearity γ is higher indicating a diffuse phase transformation.",
publisher = "Elsevier",
journal = "Ceramics International",
title = "Niobium doping effect on BaTiO3 structure and dielectric properties",
pages = "8154-8164",
volume = "46",
number = "6",
doi = "10.1016/j.ceramint.2019.12.043",
url = "https://hdl.handle.net/21.15107/rcub_dais_8964"
}

Paunović, V., Mitić, V. V., Đorđević, M.,& Prijić, Z.. (2020). Niobium doping effect on BaTiO3 structure and dielectric properties. in Ceramics International
Elsevier., 46(6), 8154-8164.
https://doi.org/10.1016/j.ceramint.2019.12.043
https://hdl.handle.net/21.15107/rcub_dais_8964

Paunović V, Mitić VV, Đorđević M, Prijić Z. Niobium doping effect on BaTiO3 structure and dielectric properties. in Ceramics International. 2020;46(6):8154-8164.
doi:10.1016/j.ceramint.2019.12.043
https://hdl.handle.net/21.15107/rcub_dais_8964 .

Paunović, Vesna, Mitić, Vojislav V., Đorđević, M., Prijić, Z., "Niobium doping effect on BaTiO3 structure and dielectric properties" in Ceramics International, 46, no. 6 (2020):8154-8164,
https://doi.org/10.1016/j.ceramint.2019.12.043 .,
https://hdl.handle.net/21.15107/rcub_dais_8964 .

TY  - JOUR
AU  - Paunović, Vesna
AU  - Mitić, Vojislav V.
AU  - Prijić, Z.
AU  - Živković, Ljiljana
PY  - 2014
UR  - https://dais.sanu.ac.rs/123456789/563
AB  - Dy/Mn doped BaTiO3 with different Dy2O3 contents, ranging from 0.1 to 5.0 at% Dy, were investigated regarding their microstructural and dielectric characteristics. The content of 0.05 at% Mn was constant in all the investigated samples. The samples were prepared by the conventional solid state reaction and sintered at 1290°, and 1350 °C in air atmosphere for 2 h. The low doped samples (0.1 and 0.5 at% Dy) exhibit mainly fairly uniform and homogeneous microstructure with average grain sizes ranged from 0.3 μm to 3.0 μm. At 1350 °C, the appearance of secondary, abnormal, grains in the fine grain matrix and core–shell structure were observed in highly doped Dy/BaTiO3. Dielectric measurements were carried out as a function of temperature up to 180 °C. The low doped samples sintered at 1350 °C, display the high value of dielectric permittivity at room temperature, 5600 for 0.1Dy/BaTiO3. A nearly flat permittivity–temperature response was obtained in specimens with 2.0 and 5.0 at% additive content. Using a Curie–Weiss and modified Curie–Weiss low, the Curie constant (C), Curie like constant (C′), Curie temperature (TC) and a critical exponent (γ) were calculated. The obtained values of γ pointed out the diffuse phase transformation in highly doped BaTiO3 samples.
PB  - Elsevier
T2  - Ceramics International
T1  - Microstructure and dielectric properties of Dy/Mn doped BaTiO3 ceramics
SP  - 4277
EP  - 4284
VL  - 40
IS  - 3
DO  - 10.1016/j.ceramint.2013.08.092
UR  - https://hdl.handle.net/21.15107/rcub_dais_563
ER  - 

@article{
author = "Paunović, Vesna and Mitić, Vojislav V. and Prijić, Z. and Živković, Ljiljana",
year = "2014",
abstract = "Dy/Mn doped BaTiO3 with different Dy2O3 contents, ranging from 0.1 to 5.0 at% Dy, were investigated regarding their microstructural and dielectric characteristics. The content of 0.05 at% Mn was constant in all the investigated samples. The samples were prepared by the conventional solid state reaction and sintered at 1290°, and 1350 °C in air atmosphere for 2 h. The low doped samples (0.1 and 0.5 at% Dy) exhibit mainly fairly uniform and homogeneous microstructure with average grain sizes ranged from 0.3 μm to 3.0 μm. At 1350 °C, the appearance of secondary, abnormal, grains in the fine grain matrix and core–shell structure were observed in highly doped Dy/BaTiO3. Dielectric measurements were carried out as a function of temperature up to 180 °C. The low doped samples sintered at 1350 °C, display the high value of dielectric permittivity at room temperature, 5600 for 0.1Dy/BaTiO3. A nearly flat permittivity–temperature response was obtained in specimens with 2.0 and 5.0 at% additive content. Using a Curie–Weiss and modified Curie–Weiss low, the Curie constant (C), Curie like constant (C′), Curie temperature (TC) and a critical exponent (γ) were calculated. The obtained values of γ pointed out the diffuse phase transformation in highly doped BaTiO3 samples.",
publisher = "Elsevier",
journal = "Ceramics International",
title = "Microstructure and dielectric properties of Dy/Mn doped BaTiO3 ceramics",
pages = "4277-4284",
volume = "40",
number = "3",
doi = "10.1016/j.ceramint.2013.08.092",
url = "https://hdl.handle.net/21.15107/rcub_dais_563"
}

Paunović, V., Mitić, V. V., Prijić, Z.,& Živković, L.. (2014). Microstructure and dielectric properties of Dy/Mn doped BaTiO3 ceramics. in Ceramics International
Elsevier., 40(3), 4277-4284.
https://doi.org/10.1016/j.ceramint.2013.08.092
https://hdl.handle.net/21.15107/rcub_dais_563

Paunović V, Mitić VV, Prijić Z, Živković L. Microstructure and dielectric properties of Dy/Mn doped BaTiO3 ceramics. in Ceramics International. 2014;40(3):4277-4284.
doi:10.1016/j.ceramint.2013.08.092
https://hdl.handle.net/21.15107/rcub_dais_563 .

Paunović, Vesna, Mitić, Vojislav V., Prijić, Z., Živković, Ljiljana, "Microstructure and dielectric properties of Dy/Mn doped BaTiO3 ceramics" in Ceramics International, 40, no. 3 (2014):4277-4284,
https://doi.org/10.1016/j.ceramint.2013.08.092 .,
https://hdl.handle.net/21.15107/rcub_dais_563 .