Dielectric Properties of CaCu3Ti4O12/Al2O3 Composites

2017 ◽  
Vol 888 ◽  
pp. 12-16
Author(s):  
Mohamad Johari Abu ◽  
Rosyaini Afindi Zaman ◽  
Mohd Fariz Ab Rahman ◽  
Mohsen Ahmadipour ◽  
Julie Juliewatty Mohamed ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Solid State Reaction Method ◽  
Boundary Resistance ◽  
Frequency Range ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
X Ray ◽  
Average Grain Size ◽  
Tan Δ ◽  
Composite Samples

In this work, (1-x)CaCu3Ti4O12/xAl2O3 (x = 0, 0.01, 0.03, 0.05 and 0.1) composite samples were prepared by the conventional solid-state reaction method. The dielectric properties of the samples were investigated at frequency range of 20 – 106 Hz. X-ray diffractogram results show that the samples with Al2O3 sintered at 1040 °C/10 h are mixed phase and consist of CaCu3Ti4O12, CuAl2O4, TiO2 and Al2O3. The average grain size of the samples increased greatly for x = 0.01, then abruptly depressed for x ≥ 0.03. Al2O3-added (x = 0.01) has been shown to increase the dielectric permittivity (ε’) up to ~5000 over frequency range of 102 – 105 Hz, while retaining the dielectric loss (tan δ ~ 0.15) at 1 kHz. With further increase of Al2O3 content, the ε’ and tan δ values of the samples are decreased monotonically in all frequency ranges. The improvement of dielectric properties in the composite sample was attributed to the enhanced grain boundary resistance.

Structural and Dielectric Properties of Na0.5Bi0.5TiO3 Ferroelectric Ceramics

2012 ◽  
Vol 585 ◽  
pp. 219-223
Author(s):  
Rekha Kumari ◽  
N. Ahlawat ◽  
Ashish Agarwal ◽  
M. Sindhu ◽  
N.N. Ahlawat
Keyword(s):  
Dielectric Properties ◽  
Solid State Reaction Method ◽  
Wide Frequency Range ◽  
Ferroelectric Ceramics ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
X Ray ◽  
Different Temperatures

Na0.5Bi0.5TiO3 (NBT) ceramics were synthesized by conventional solid state reaction method. Structural and dielectric properties of these ceramics were investigated. Crystalline phase of sintered ceramics was investigated by X-ray diffraction (XRD). The Rietveld refinement of powder X-ray diffraction revealed that the prepared ceramics exhibit the rhombohedral space group R3c. Dielectric properties of Na0.5Bi0. analyzer.5TiO3 (NBT) ceramics were studied at different temperatures in a wide frequency range using impedance

Temperature Dependence on Dielectric Response of La0.7Ba0.3Mn0.4Ti0.6O3 Ceramic

2015 ◽  
Vol 1107 ◽  
pp. 45-52
Author(s):  
Aaliyawani Ezzerin Sinin ◽  
Walter Charles Primus ◽  
Abdul Halim Shaari ◽  
Zainal Abidin Talib ◽  
Sinin Hamdan
Keyword(s):  
Dielectric Properties ◽  
Temperature Dependence ◽  
Low Frequency ◽  
Sintered Sample ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Low Frequencies ◽  
X Ray ◽  
Lcr Meter

Ceramic sample of La0.70Ba0.30Mn0.40Ti0.60O3 oxide has been prepared by the conventional solid-state reaction method. The sintered sample was characterized by using x-ray diffraction (XRD) and low frequency LCR meter. XRD result shows that the sample has a cubic structure with the existence of impurity phase. The dielectric properties of La0.70Ba0.30Mn0.40Ti0.60O3 measured from room temperature to 200°C shows that the dielectric permittivity is temperature dependence with strong dispersion at low frequencies. A circuit model based on the universal capacitor response function is also being used to represent the dielectric properties of the sample.

Dielectric Properties of Ba(Mg0.2/3Zn0.8/3Nb2/3)O3 and Ba1-xSrx(Mg0.2/3Zn0.8/3Nb2/3)O3 Microwave Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 272-274
Author(s):  
S.S. Cheng ◽  
J. Luo ◽  
Zhao Xian Xiong
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Resonant Frequency ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Zero Temperature ◽  
Microwave Ceramics ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Zn Ions

Microwave ceramics of Ba(Mg0.2/3Zn0.8/3Nb2/3)O3 and Ba1-xSrx(Mg0.2/3Zn0.8/3Nb2/3)O3 were synthesized with conventional solid-state reaction method. Dielectric properties of the samples were studied as functions of compositions and sintering temperatures. Experimental results show that a higher Q×f value is reached by substituting Zn ions with Mg ions and a near-zero temperature coefficient of resonant frequency is obtained by replacing Ba ions with Sr ions.

Photoluminescence properties of Na1.45La8.55(SiO4)6(F0.9O1.1):Eu for applications as a reddish orange phosphor

2014 ◽  
Vol 07 (05) ◽  
pp. 1450060 ◽  
Author(s):  
Qun Shi ◽  
Dhia A. Hassan ◽  
Renjie Zeng
Keyword(s):  
Spectral Analysis ◽  
Solid State Reaction Method ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
X Ray ◽  
Analysis System ◽  
Reddish Orange ◽  
The Eu

Europium-doped Na 1.45 La 8.55-8.55x( SiO 4)6( F 0.9 O 1.1)(0.000 ≤ x ≤ 0.045) phosphors were prepared by a conventional solid-state reaction method at 1200°C and their properties were studied by X-ray diffraction (XRD), and a spectral analysis system. No impurities were observed. The phosphor could be excited at 254 nm, 395 nm and 465 nm to yield a reddish orange emission which was attributed to the 5 D 0 → 7 F j (j = 0–2) transitions of the Eu ion.

Structural, dielectric, ferroelectric and impedance spectroscopic studies on Ba1−xSrxTiO3(0.15 ≤ x ≤ 0.35)

2019 ◽  
Vol 33 (17) ◽  
pp. 1950193 ◽  
Author(s):  
Shukdev Pandey ◽  
Om Parkash ◽  
Devendra Kumar
Keyword(s):  
Equivalent Circuit Model ◽  
Solid State Reaction Method ◽  
Spectroscopic Studies ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
X Band ◽  
Xrd Patterns ◽  
Diffuse Phase

Compositions with x = 0.15, 0.20, 0.25, 0.30 and 0.35 were synthesized in the system [Formula: see text] using conventional solid state reaction method and characterized by X-Ray Diffraction (XRD), Raman spectroscopy and Scanning Electron Microscopy (SEM). Tetragonal phase was confirmed in all the samples using Rietveld refinement of the XRD patterns and observation of their Raman spectra. Dielectric and impedance measurements were carried out in the temperature range 300–723 K in the frequency range 1 Hz to 1 MHz. The samples exhibit diffuse phase transition (DPT). Equivalent circuit model involving combination of Constant Phase angle Elements (CPE) and resistances (R) was developed which represents the data well. Expressions for the values of resistances (R) were established in terms of composition and temperature empirically. P-E loops indicated normal ferroelectric behavior for all the samples. Dielectric constant was also measured in the frequency range 8–12 GHz in the X band of microwaves.

Dielectric Properties of Zr-Doped CaCu3Ti4O12 Ceramics

2008 ◽  
Vol 368-372 ◽  
pp. 129-131
Author(s):  
Yong He ◽  
Ke Pi Chen ◽  
Dong Yu Liu ◽  
Zong De Liu
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Solid State ◽  
Impedance Spectroscopy ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Conventional Solid State Reaction ◽  
Obvious Effect ◽  
Reaction Method ◽  
Microstructure Characteristic

CaCu3(Ti1-xZrx)O12 ceramics (x = 0.02, 0.04, 0.06, 0.08) were prepared by the conventional solid-state reaction method. Phase compositions, microstructure and dielectric properties were examined by XRD, SEM and impedance spectroscopy, respectively. The experimental results indicated that there is no obvious effect on microstructure characteristic by substituting Zr4+ for Ti4+. It was found that the values of the dielectric constant for all of the samples dropped into the order of 102, which is significantly lower than the order of 105 that of normally reported in the literature. It was suggested that the presence of impurity phases played an important role for the degeneracy of dielectric properties.

Structural, magnetic and dielectric properties of the Aurivillius phase Bi6Fe2−xMnxTi3O18 (0 ≤ x ≤ 0.8)

RSC Advances ◽  
2014 ◽  
Vol 4 (87) ◽  
pp. 46704-46709 ◽  
Author(s):  
Xuzhong Zuo ◽  
Jie Yang ◽  
Bin Yuan ◽  
Dongpo Song ◽  
Xianwu Tang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Aurivillius Phase ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Magnetic And Dielectric Properties

The n = 5 Aurivillius phase ceramics Bi6Fe2−xMnxTi3O18 (BFMTO) (0 ≤ x ≤ 0.8) were synthesized with a conventional solid-state reaction method.

scholarly journals Effect of V2O5 B-site substitution on the microstructure, Raman spectrum, and dielectric properties of SrBi2Ta2O9 ceramics

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Chia-Ching Wu ◽  
Cheng-Fu Yang
Keyword(s):  
Raman Spectrum ◽  
Dielectric Properties ◽  
Solid State Reaction Method ◽  
Layered Perovskite ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Strontium Bismuth Tantalate ◽  
Reaction Method ◽  
X Ray ◽  
Ferroelectric Characteristic

Abstract Strontium bismuth tantalate vanadate [SrBi2(Ta2−xVx)O9, SBTV] ceramics, which are bismuth-layered perovskite ferroelectrics, were synthesized through the solid-state reaction method. The effects of different sintering temperatures and V2O5 contents on the structure of the microstructure, Raman spectrum, and dielectric properties of the SBTV ceramics were investigated. As sintered at high temperature (980–1040 °C) and different V2O5 contents (x = 0.1 − x = 0.4), only disk-like grains of the SBTV ceramics were observed in the scanning electron micrographs. Preferential orientation of the crystals of the SBTV ceramics was confirmed through X-ray diffraction studies. The higher dielectric constant and Curie temperature of the SBTV ceramics compared with those of strontium bismuth tantalite (SrBi2Ta2O9, SBT) ceramics are ascribe to the partial replace of Ta5+ ions by V5+ ions in the B sites. The Curie–Weiss law and the modified Curie–Weiss law were used to discuss the normal-type or relaxor-type ferroelectric characteristic of the SBTV ceramics. The Ta5+ ion replaced by V5+ ion site in SBT ceramics to form SBTV ceramics exerted a pronounced effect on the BO6 mode, as demonstrated by Raman spectrum results.

Electrical Properties of a High-Tc Superconductor-Polymer Compersite

2007 ◽  
Vol 546-549 ◽  
pp. 1989-1992
Author(s):  
Fang Gao Chang ◽  
Kun Fang ◽  
Gui Lin Song
Keyword(s):  
Annealing Temperature ◽  
Solid State Reaction Method ◽  
Gravimetric Analysis ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Different Temperatures ◽  
Zero Resistance ◽  
Composite Samples

A superconductor-polymer composite of Bi1.8Pb0.4Sr2Ca2Cu3Oy and ethylene propylene rubber (EPR) was prepared by conventional solid-state reaction method. The phase structure of the composite was characterized by using x-ray diffraction technique. The resistivity of composite samples annealed at different temperatures was measured between 40K and 300K. The results indicate that the resistivity of the as-prepared composite increases with increasing EPR content and shows essentially a semiconducting behavior above Tc. For fixed EPR content, the resistivity of composite samples decreases with increasing annealing temperature. The composite begins to show some signs of superconducting transition at an annealing temperature of 700 °C and zero resistance is reached for samples sintered at 800°C. Thermal gravimetric analysis (TGA) on the composite confirmed that 65% of the EPR content still present in the superconducting composite samples. SEM was used to investigate the surface morphology of the composites. Preliminary results show that the mechanical properties of the composite have been much improved compared with its parent superconductor ceramics.

Study on the Property of Bi2(Mg2/3Nb1.1833Sn0.15)O7 Dielectric Ceramics Doped with Li2CO3

2012 ◽  
Vol 549 ◽  
pp. 749-752
Author(s):  
Hai Tang Hua ◽  
Xin You Huang ◽  
Zhi Wen Zhu ◽  
Yin Qun Hua ◽  
Yan Li
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Solid State ◽  
Dielectric Loss ◽  
Solid State Reaction ◽  
Piezoelectric Ceramics ◽  
Solid State Reaction Method ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Dielectric Ceramics

(Bi2-xLix) (Mg2/3Nb1.1833Sn0.15)O7 piezoelectric ceramics were prepared by conventional solid state reaction method. The microstructure and dielectric properties of dielectric ceramics were studied which was doped by different amount of Li2CO3. The experiment results showed that the density of the ceramics would decrease, but have little effect on the microstructure of the ceramics when the amount of the Li2CO3 doped increases. With the increasing of Li2CO3 doped, the dielectric constant(εr) and dielectric loss(tanδ) of dielectric ceramics first decreases and then increases. When tested in 1MHz frequency, the piezoelectric ceramics display the optimum properties tanδ is 0.00009, εr is 163 while Li2CO3 doped amount is 0.05 mol%.

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