scholarly journals Electrical characterization and impedance response of lanthanum doped barium titanate ceramics

2008 ◽  
Vol 40 (3) ◽  
pp. 283-294 ◽  
Author(s):  
D. Mancic ◽  
V. Paunovic ◽  
M. Vijatovic ◽  
B. Stojanovic ◽  
Lj. Zivkovic
Keyword(s):  
Dielectric Permittivity ◽  
Pechini Method ◽  
Electrical Characterization ◽  
Dissipation Factor ◽  
Electrical Circuit ◽  
Impedance Response ◽  
Modified Pechini Method ◽  
Titanate Ceramics ◽  
Constant Phase Elements ◽  
La Doped

The dielectric permittivity and dissipation factor of La-doped and undoped BaTiO3 were investigated as a function of frequency and temperature. The impedance response was used to study the electrical properties of La-doped BaTiO3 over the temperature range from room temperature (RT) to 350?C. La-doped and undoped BaTiO3, obtained by a modified Pechini method, were sintered in air at 1300?C for 2 and 16 hours. The impedance spectra were analyzed in terms of equivalent circuits involving resistors, capacitors and constant phase elements (CPE). The most suitable electrical circuit for the interpretation of experimental results is found to be the equivalent circuit consisting of resistors and CPE elements which replace the capacitor elements. The contribution of grain boundary resistance to the total resistance of a system is remarkable at low temperature. Dielectric permittivity of doped BaTiO3 was in the range of 8000 to 12000 at 1 kHz and the dissipation factor was less than 1%.

scholarly journals Dielectric properties of La/Mn codoped barium titanate ceramics

2016 ◽  
Vol 29 (2) ◽  
pp. 285-296 ◽  
Author(s):  
Vesna Paunovic ◽  
Vojislav Mitic ◽  
Milos Marjanovic ◽  
Ljubisa Kocic
Keyword(s):  
Dielectric Properties ◽  
Pechini Method ◽  
Local Area ◽  
Dissipation Factor ◽  
Curie Constant ◽  
Weiss Temperature ◽  
Fine Grained ◽  
Average Grain Size ◽  
Titanate Ceramics ◽  
La Doped

La/Mn codoped BaTiO3 ceramics with various La2O3 content, ranging from 0.3 to 1.0 at% La, were investigated regarding their microstructure and dielectric properties. The content of MnO2 was kept constant at 0.01 at% Mn in all samples. La/Mn codoped and undoped BaTiO3 were obtained by a modified Pechini method and sintered in air at 13000C for two hours. The homogeneous and completely fine-grained microstructure with average grain size from 0.5 to 1.5mm was observed in samples doped with 0.3 at% La. In high doped samples, apart from the fine grained matrix, the appearance of local area with secondary abnormal grains was observed. The dielectric properties were investigated as a function of frequency and temperature. The dielectric permittivity of the doped BaTiO3 was in the range of 3945 to 12846 and decreased with an increase of the additive content. The highest value for the dielectric constant at room temperature (er= 12846) and at the Curie temperature (er= 17738) were measured for the 0.3 at% La doped samples. The dissipation factor ranged from 0.07 to 0.62. The Curie constant (C), Curie-Weiss temperature (T0) and critical exponent (g) were calculated using the Curie-Weiss and the modified Curie-Weiss law. The highest values of Curie constant (C=3.27?105 K) was measured in the 1.0 at% La doped samples. The obtained values for g ranged from 1.04 to 1.5, which pointed out the sharp phase transformation from the ferroelectric to the paraelectric phase.

X-ray powder diffraction data of LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites

2021 ◽  
pp. 1-6
Author(s):  
Mariana M. V. M. Souza ◽  
Alex Maza ◽  
Pablo V. Tuza
Keyword(s):  
Crystal Structure ◽  
Rietveld Method ◽  
Pechini Method ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Modified Pechini Method ◽  
Scanning Electron

In the present work, LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites were synthesized by the modified Pechini method. These materials were characterized using X-ray fluorescence, scanning electron microscopy, and powder X-ray diffraction coupled to the Rietveld method. The crystal structure of these materials is orthorhombic, with space group Pbnm (No 62). The unit-cell parameters are a = 5.535(5) Å, b = 5.527(3) Å, c = 7.819(7) Å, V = 239.2(3) Å3, for the LaNi0.5Ti0.45Co0.05O3, a = 5.538(6) Å, b = 5.528(4) Å, c = 7.825(10) Å, V = 239.5(4) Å3, for the LaNi0.45Co0.05Ti0.5O3, and a = 5.540(2) Å, b = 5.5334(15) Å, c = 7.834(3) Å, V = 240.2(1) Å3, for the LaNi0.5Ti0.5O3.

Synthesis and Characterization of Multiferroic NiFe2O4/BiFeO3 Nanocomposites by Modified Pechini Method

2011 ◽  
Vol 197-198 ◽  
pp. 456-459
Author(s):  
Xian Ming Liu ◽  
Wen Liang Gao
Keyword(s):  
Pechini Method ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Magnetic Bias ◽  
Field Frequency ◽  
Magnetic Field Frequency ◽  
X Ray ◽  
Structure And Morphology ◽  
Modified Pechini Method

Spinel-perovskite multiferroics of NiFe2O4/BiFeO3 nanoparticles were prepared by modified Pechini method. The structure and morphology of the composites were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the composites consisted of spinel NiFe2O4 and perovskite BiFeO3 after annealed at 700°C for 2h, and the particle size ranges from 40 to 100nm. VSM and ME results indicated that the nanocomposites exhibited both tuning magnetic properties and a ME effect. The ME effect of the nanocomposites strongly depended on the magnetic bias and magnetic field frequency.

SrSnO3 perovskite obtained by the modified Pechini method—Insights about its photocatalytic activity

2019 ◽  
Vol 369 ◽  
pp. 181-188 ◽  
Author(s):  
Ana Rita Ferreira Alves Teixeira ◽  
Alex de Meireles Neris ◽  
Elson Longo ◽  
José Rodrigues de Carvalho Filho ◽  
Amer Hakki ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Pechini Method ◽  
Modified Pechini Method

scholarly journals Electrical and Dielectric Characterization of Bi12GeO20Prepared by Modified Pechini Method

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
C. G. P. Moraes ◽  
F. A. A. Jesus ◽  
Z. S. Macedo
Keyword(s):  
Volume Fraction ◽  
Pechini Method ◽  
Dark Conductivity ◽  
High Frequencies ◽  
Dielectric Characterization ◽  
Calcination Temperatures ◽  
Grain Sizes ◽  
Synthesis Parameters ◽  
Modified Pechini Method

Bismuth germanate (Bi12GeO20) ceramics were produced using modified Pechini route, and the synthesis parameters, crystalline phases, microstructure, and sintering conditions were investigated.Bi12GeO20powders with submicrometric particle sizes were investigated for calcination temperatures from 400 to 600°C, with soaking times of 1 h and 5 h. Controlling the synthesis parameters, dense ceramics with two different grain sizes of 3.4 ± 0.5 µm and 5.7 ± 0.8 µm could be produced after sintering at 750°C/1 h. The electric and dielectric properties of these ceramics were determined by impedance spectroscopy (IS). From the results, it was concluded that the dielectric permittivity measured at high frequencies is insensitive to the grain size, while the AC dark conductivity presents a noticeable dependency on this feature. This behaviour was discussed on the basis of a Maxwell-Wagner interfacial relaxation, whose intensity depends directly on the volume fraction of grain boundaries in the sample.

Multiferroic properties of Bi0.5K0.5TiO3–BiFe1−xCoxO3 (0 ≤ x ≤ 0.2) solid solution

RSC Advances ◽  
2015 ◽  
Vol 5 (126) ◽  
pp. 104210-104215 ◽  
Author(s):  
X. Z. Zuo ◽  
J. Yang ◽  
B. Yuan ◽  
X. C. Kan ◽  
Lin Zu ◽  
...  
Keyword(s):  
Solid Solution ◽  
Pechini Method ◽  
Ferroelectric Properties ◽  
Lead Free ◽  
Multiferroic Properties ◽  
Modified Pechini Method

We have successfully prepared a binary lead-free solid-solution of Bi0.5K0.5TiO3–BiFe1−xCoxO3 using a modified Pechini method and investigated the magnetic and ferroelectric properties of Bi0.5K0.5TiO3–BiFe1−xCoxO3 (0 ≤ x ≤ 0.2).

Structural and photocatalytic properties of Mg2SnO4 spinel obtained by modified Pechini method

2019 ◽  
Vol 236 ◽  
pp. 320-323 ◽  
Author(s):  
J.M. Costa ◽  
L.C. Lima ◽  
M.S. Li ◽  
I.M.G. Santos ◽  
M.R.S. Silva ◽  
...  
Keyword(s):  
Pechini Method ◽  
Photocatalytic Properties ◽  
Modified Pechini Method

Electrical characterization of porous La-doped BaSnO3 using impedance spectroscopy

Ionics ◽  
2015 ◽  
Vol 21 (10) ◽  
pp. 2825-2838 ◽  
Author(s):  
Md. Jawed Ansaree ◽  
Shail Upadhyay
Keyword(s):  
Impedance Spectroscopy ◽  
Electrical Characterization ◽  
La Doped
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