scholarly journals Study of the influence of 2.5% Mg2+ insertion in the B-site of La0.8Ca0.1Pb0.1FeO3 on its structural, electrical and dielectric properties

RSC Advances ◽  
2021 ◽  
Vol 11 (52) ◽  
pp. 33070-33080
Author(s):  
H. Issaoui ◽  
A. Benali ◽  
F. Issaoui ◽  
E. Dhahri ◽  
B. F. O. Costa ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Impedance Spectroscopy ◽  
Physical Properties ◽  
Complex Impedance ◽  
Experimental Techniques ◽  
Complex Impedance Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrical And Dielectric Properties

This work involves the synthesis and study of physical properties of the La0.8Ca0.1Pb0.1Fe0.975Mg0.025O3 compound, which has been characterized by various experimental techniques, such as X-ray diffraction, SEM and complex impedance spectroscopy.

Characterization, Optical and Impedance Study of ZnSe Nanostructure

2013 ◽  
Vol 699 ◽  
pp. 490-495
Author(s):  
Ramna Tripathi ◽  
Akhilesh Kumar
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Impedance Spectroscopy ◽  
Zinc Selenide ◽  
Relaxation Times ◽  
Complex Impedance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
The Stability

Zinc selenide nanoparticle has been synthesized using soft chemical routes. The particles were capped using 2-mercaptoethanol to achieve the stability and avoid the coalescence. The as-obtained particles were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), UV–VIS absorption and photoluminescence (PL) spectra. The impedance studies were carried out as a function of frequency (100 Hz–1 MHz) and temperature (298–373 K) by impedance spectroscopy. An analysis of the complex impedance (z' and z") with frequency is performed assuming a distribution of relaxation times.

scholarly journals Effect of Fe Substitution on the Structural, Electrical and Dielectric Properties of La0.70Ca0.30MnO3 Cathode for SOFCs

2019 ◽  
Vol 9 (1) ◽  
pp. 324-328
Keyword(s):  
Dielectric Properties ◽  
Single Phase ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Suitable Material ◽  
Density Values ◽  
Electrical And Dielectric Properties ◽  
Fe Substitution

Perovskite solid solutions (La0.70Ca0.30)(FexMn1-x)O3 where x = 0.01, 0.20, 0.30 and 0.40 ceramics were synthesized by solid state reaction route. The structural studies were carried by X-Ray diffraction method and the observed results have indicated that all the prepared samples were crystallized into single phase. The surface morphology was studied by Scanning Electron Microscopy and the images have revealed that grain size has increased with the increasing concentration of Fe. Archimedes principle was used to calculate the density of all the sintered samples and the density values were observed to be in increasing order. The impedance and dielectric properties have been characterized at different ranges of temperature and frequency. The value of electrical conductivity were found to be more than 100 S cm-1 , which indicate that the synthesized material is suitable material for cathode of Solid Oxide Fuel Cell.

Complex impedance spectroscopy and ionic transport properties of natural leucite, K0.90Na0.08[Al0.98Si2.02]O6, as a function of temperature and pressure

2010 ◽  
Vol 74 (3) ◽  
pp. 507-519 ◽  
Author(s):  
R. L. Jones ◽  
M. Thrall ◽  
C. M. B. Henderson
Keyword(s):  
Dielectric Properties ◽  
Impedance Spectroscopy ◽  
Transport Properties ◽  
Complex Impedance ◽  
Ionic Transport ◽  
Ionic Mobility ◽  
Activation Energies ◽  
Complex Impedance Spectroscopy ◽  
Phase Assemblage ◽  
Temperature And Pressure

AbstractThe temperature (T) and pressure (P) dependence of dielectric and conductivity properties of natural leucite were determined using complex impedance spectroscopy at frequencies from 103 to 106 Hz. Experiments were carried out in a Walker multi-anvil cell at 1 atm and P from 2.5 to 6 GPa and at T from 350 to 800°C. At pressure >6 GPa and temperature >790°C the leucite broke down to kalsilite+sanidine and dielectric properties for this phase assemblage are given at 6.0–7.0 GPa and T to 1050°C.Leucite conductivity increases with increasing T and decreases with increasing P reflecting their different effects on migration of K cations within the channels in the leucite aluminosilicate framework. Activation energies for K+ migration in leucite increase with increasing pressure (0.74–0.97 eV; 70.0–93.2 kJ/mol) and activation volumes for leucite increase with increasing T (6.42–9.51 cm3/mol; 400–700°C). The latter data provide model K+ cation diameters increasing from 2.7 Å at 400°C to 3.2 Å at 700°C. These values are consistent with the earlier suggestion of Palmer and Salje that the ionic mobility mechanism consists of diffusion along <110> rather than along the main channels parallel to <111>.

COMPLEX IMPEDANCE SPECTROSCOPY ON ZnO-B2O3 DOPED (Ba, Sr)TiO3 CERAMICS

2010 ◽  
Vol 17 (01) ◽  
pp. 27-32 ◽  
Author(s):  
SANG-HO MOON ◽  
YONG-SU HAM ◽  
JUNG-HYUK KOH
Keyword(s):  
Impedance Spectroscopy ◽  
Complex Impedance ◽  
Negative Temperature ◽  
Nyquist Plot ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Bst Ceramics ◽  
Grain Growth Behavior ◽  
Microscopy Images

BST ceramics with doping of 1, 3, and 5 wt.% ZnBO were prepared by the conventional mixed oxide method and sintered at 1100°. X-ray diffraction analyses were carried out to verify the structural properties. 1, 3, and 5 wt.% ZnBO doped BST ceramics were crystallized with weak tetragonal structure at 1100°C. The grain growth behavior and shapes were investigated by scanning electron microscopy images. The electrical properties of 1, 3, and 5 wt.% ZnBO doped BST ceramics were investigated by impedance spectroscopy at the different temperatures (350, 375, and 400°C). Impedance spectroscopy data presented in Nyquist plot show the existence of both grain and grain boundary effects in all specimens. 1, 3, and 5 wt.% ZnBO doped BST ceramics showed negative temperature coefficient of resistance (NTCR). Also, the capacitances and resistances of grains and grain boundaries for 1, 3, and 5 wt.% doped BST ceramics were simulated through equivalent circuit with the parallelly connected capacitors and resistors. The capacitance and resistance were decreased when temperature and ZnBO dopants were increased.

scholarly journals Electrical and Dielectric Properties of Polyaniline and Polyaniline/Montmorillonite Nanocomposite Prepared by Solid Reaction Using Spectroscopy Impedance

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Imene Bekri-Abbes ◽  
Ezzeddine Srasra
Keyword(s):  
Dielectric Properties ◽  
Complex Impedance ◽  
Gravimetric Analysis ◽  
Electrical Measurements ◽  
Solid Reaction ◽  
X Ray ◽  
Impedance Technique ◽  
Different Temperatures ◽  
Electrical And Dielectric Properties ◽  
Uv Visible

The combination of two components with uniform distribution in nanoscale is expected to facilitate wider applications of the material. In this study, polyaniline (PAn) and polyaniline/montmorillonite (Mt) nanocomposite were prepared by solid reaction using persulfate of ammonium as oxidant. The phase composition and morphology of the nanocomposite were characterized by FTIR, UV-visible spectroscopy, X-ray diffractometer, thermal gravimetric analysis, and scanning electron microscopy. The electrical and dielectric properties were determined using spectroscopy impedance. The analysis of UV-visible and FTIR spectroscopy demonstrated that aniline chloride has been polymerized into PAn in its conducting emeraldine form. Thermogravimetric analysis suggested that PAn chains intercalated in the clay host are more thermally stable than those of free PAn prepared by solid-solid reaction. Electrical measurements were carried out using the complex impedance technique in the frequency range of 10−2to 104 Hz at different temperatures. The ac conductivity data of different nanocomposites were analyzed as a function of frequency and temperature. It has been found that the incorporation of inorganic clay phase into polyaniline matrix has an effect on the electrical and dielectric properties of the nanomaterial.

scholarly journals Effect of Zinc Doping on the Electrical and Dielectric Properties of CCTO Compound Synthesized by Solid-State Method

2021 ◽  
Vol 33 (9) ◽  
pp. 2000-2006
Author(s):  
M. Slaoui ◽  
N. Gouitaa ◽  
Y. El Issmaeli ◽  
A. Harrach ◽  
F. Abdi ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Solid State ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray ◽  
Zn Concentration ◽  
Zinc Doping ◽  
Electrical And Dielectric Properties

In this work, the influence of zinc doping on structural and dielectric properties of CaCu(3-x)ZnxTi4O12 (CCZxTO with x = 0, 2.5, 5, 7.5, 10, 12.5 and 15%) ceramics sintered at 1000 ºC for 8 h was studied. The ceramic samples were prepared by the conventional solid-state and calcined at 1050 ºC for 4 h. The X-ray diffraction (XRD) analysis of pure and Zn-doped CCTO were analyzed by using Rietveld refinement with cubic CCTO phase with no trace impurity phase. The scanning electron microscopy (SEM) investigation showed that for Zn-doped CCTO, the grains distributions were homogenous with average sizes which decreased with increasing of Zn concentration. The dielectric permittivity as function of temperature showed two dielectric anomalies (weakly and strong) and the dielectric constant value largely decreased for x = 2.5%, which is about tree magnitude smaller than the pure ceramic. Then it increased and reached a maximum at x = 10%, which is larger than the value of pure ceramic. And for x > 10%, the dielectric constant decreased for about two magnitude smaller than the ceramic at x = 10%. The cole-cole diagramm for all the samples showed existence of two semi-arcs attributed to the grains and grains boundaries. It was found that the Rg values were much smaller than the Rgb value. This give an evidance on the formation of interior barrier layer capacity (IBLC).

scholarly journals Synthesis by Hydrothermal Treatment of ZnO-Based Varistors Doped with Rare Earth Oxides and Their Characterization by Impedance Spectroscopy

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1134
Author(s):  
J. Porcayo-Calderon ◽  
J.J. Ramos-Hernandez ◽  
C.D. Arrieta-Gonzalez ◽  
J.G. Chacon-Nava ◽  
J.G. Gonzalez-Rodriguez ◽  
...  
Keyword(s):  
Rare Earth ◽  
Impedance Spectroscopy ◽  
Hydrothermal Treatment ◽  
Rare Earth Oxide ◽  
Rare Earth Oxides ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrical And Dielectric Properties ◽  
Ceramic Varistor

ZnO-based ceramic varistors have shown excellent electrical and dielectric properties due to their characteristics microstructures represented by the arrangement of their grains and grain boundaries that allow the absorption and flow of energy when subjected to an electrical surge. Their properties and characteristics depend on their chemical compositions and processing routes. Typical processing routes involve several stages of grinding and precalcination—which are time consuming processes. Because of this, this study proposes a simpler and cheaper alternative route for processing ceramic varistors. The alternative process proposed is the mixing of the precursor oxides by means of a hydrothermal treatment. The characteristics and properties of the synthesized ceramic varistors were evaluated by means of scanning electron microscopy, X-ray diffraction and impedance spectroscopy, considering the effect of the addition of rare earth oxides (La2O3, CeO2 and Nd2O3). The results showed that the mixing of the oxides through hydrothermal treatment produces ceramic varistors with characteristics and properties similar to those obtained by other processing routes. Furthermore, it was observed that the addition of rare earth oxides affects the characteristics and properties of the ceramic varistor depending on the type of rare earth oxide added, its concentration and ionic radius.

Dielectric Properties of La, Sm Ion-Doped BST-Based Ceramics

2011 ◽  
Vol 211-212 ◽  
pp. 1027-1030
Author(s):  
Zhan Shen Zheng ◽  
Hong Kui Hu ◽  
Rui Jiao Li ◽  
Pei Qi Yan ◽  
Yuan Liang Li ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Dielectric Property ◽  
Low Temperature ◽  
Conventional Method ◽  
Matrix Material ◽  
Complex Impedance ◽  
X Ray Diffraction ◽  
Testing Instrument ◽  
X Ray ◽  
Impedance Testing

It is important to develop a new special material to meet the requirement of advanced industry. The BST (Ba0.8Sr0.2TiO3) ceramics doped La2O3 and Sm2O3 was fabricated by the conventional method, and was tested by X-ray diffraction (XRD), Complex Impedance Testing Instrument, LCR Tester with temperature controlling systems. The results indicate that dielectric property of BST-based ceramics doped 0.05 mol% La2O3 and 0.2 mol% Sm2O3 simultaneously is the best, and Sm2O3 had applications of removing Tc of matrix material to a low temperature and making peak wider. The calcining temperature of samples was 1280 °C.

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