Dependence of the Ni0.4Zn0.6Fe2O4 spinel ferrite on frequency and temperature using impedance spectroscopy tool

Impedance Plane ◽

Different Temperatures

Abstract Ni0.4Zn0.6Fe2O4 ferrites were prepared by the conventional solid-state method. The X-ray study allowed the identification of a single orthorhombic phase. The conductivity of the prepared sample was measured at different frequencies in the temperature range 340 K to 600 K. The obtained results are discussed in terms of charge carriers hopping. We showed that the dielectric permittivity is high at different temperatures and various frequencies. The impedance plane findings present semicircle arcs at various temperatures and an electrical equivalent circuit was determined. In addition, the obtained two relaxation times were established as a function of temperature.

Study of Tantalum Substituted Potassium Tungsten Bronzes

Journal of Bangladesh Chemical Society ◽

10.3329/jbcs.v25i1.11770 ◽

2012 ◽

Vol 25 (1) ◽

pp. 38-45 ◽

Cited By ~ 1

Author(s):

Md Mahbubur R Shakil ◽

Tapas Debnath ◽

Claus H Ruscher ◽

Altaf Hussain

Keyword(s):

Cell Parameter ◽

Tungsten Bronze ◽

Chemical Society ◽

Metallic Phase ◽

Solid State Method ◽

X Ray ◽

Cell Parameters ◽

Infrared Absorption Spectra ◽

Two Phases

A series of compounds KxTayW1-yO3 with x = 0.30, 0.00 ? y ? 0.30 and x = 0.55, 0.00 ? y ? 0.10 were synthesized by conventional solid-state method. The samples were characterized using XRD and FTIR spectroscopy. X-ray powder patterns reveal that the samples with compositions x = 0.30, y ? 0.30 show hexagonal tungsten bronze (HTB) type phase and the samples with x = 0.55, 0.02 ? y ? 0.10 show a mixture of two phases (K-HTB and tetragonal potassium tungsten bronze, K-TTB). The samples of the system, K0.30TayW1-yO3 with 0.00 ? y ? 0.15 shows no significant change in the cell parameters. However, for the composition y > 0.15, the cell parameter a decreases and c increases with increasing Ta content, which may be explained by the ordering of Ta for y > 0.15 suggesting the transformation to another space group. The appearance of absorption peak in the infrared absorption spectra of K0.3TayW1-yO3, y > 0.10 samples indicate the transition to non-metallic phase. DOI: http://dx.doi.org/10.3329/jbcs.v25i1.11770 Journal of Bangladesh Chemical Society, Vol. 25(1), 38-45, 2012

Deciphering the intrinsic dynamics from the beam-induced atomic motions in oxide glasses

Journal of Synchrotron Radiation ◽

10.1107/s1600577520009753 ◽

2020 ◽

Vol 27 (5) ◽

pp. 1247-1252

Author(s):

Yuriy Chushkin

Keyword(s):

Relaxation Time ◽

Structural Relaxation ◽

Photon Correlation Spectroscopy ◽

Relaxation Times ◽

Correlation Spectroscopy ◽

Oxide Glasses ◽

Photon Correlation ◽

X Ray ◽

Different Temperatures ◽

Measured Relaxation

Probing the microscopic slow structural relaxation in oxide glasses by X-ray photon correlation spectroscopy (XPCS) revealed faster than expected dynamics induced by the X-ray illumination. The fast beam-induced dynamics mask true slow structural relaxation in glasses and challenges application of XPCS to probe the atomic dynamics in oxide glasses. Here an approach that allows estimation of the true relaxation time of the sample in the presence of beam-induced dynamics is presented. The method requires two measurements either with different X-ray beam intensities or at different temperatures. Using numerical simulations it is shown that the slowest estimated true relaxation time is limited by the accuracy of the measured relaxation times of the sample. By analyzing the reported microscopic dynamics in SiO2, GeO2 and B2O3 glasses, it is concluded that the beam-induced dynamics show rich behavior depending on the sample.

Microwave Absorption Performance of La0.7 Sr0.3 MnO3 with Different Sintering Temperatures

10.4028/www.scientific.net/amr.415-417.1399 ◽

2011 ◽

Vol 415-417 ◽

pp. 1399-1402 ◽

Cited By ~ 2

Author(s):

Shu Yuan Zhang ◽

Quan Xi Cao

Keyword(s):

Low Frequency ◽

Network Analyzer ◽

X Ray Diffraction ◽

Solid State Method ◽

Pure Perovskite Structure ◽

X Ray ◽

Different Temperatures ◽

Absorption Performance ◽

Microwave Absorption Performance ◽

Traditional Solid State Method

La 0.7 Sr 0.3 MnO 3 powders have been synthesized at different temperatures by the traditional solid state method. The crystal structures have been characterized by X-ray diffraction (XRD). The electromagnetic parameters were measured by vector network analyzer (VNA) within the frequency range of 5.85-18GHz. It’s found that the pure perovskite structure has been obtained at the temperature of 1000°C. The bandwidth for R<-6dB became thinner with the sintering temperature’s increase from 1000°C to 1150°C, and the absorbing peak moves to the higher frequency first and low frequency then, the absorbing peak is enhanced first and weakened then.

Solid Solutions Study of BaTiO3 Doped on B Site by Electronic Compensation

10.4028/www.scientific.net/amr.976.30 ◽

2014 ◽

Vol 976 ◽

pp. 30-35

Author(s):

Francisco Raúl Barrientos-Hernández ◽

Alberto Arenas-Flores ◽

Iván Alonso Lira Hernández ◽

Carlos Gómez-Yáñez ◽

Miguel Pérez Labra

Keyword(s):

Room Temperature ◽

Hexagonal Phase ◽

Ferroelectric Properties ◽

X Ray Diffraction ◽

Electrical Measurements ◽

Solid State Method ◽

X Ray ◽

Air Atmosphere ◽

Electronic Compensation

Several compositions of BaTiO:Nb5+ were made by conventional solid-state method in air atmosphere, according to the general formula BaTi1-xNbxO3; (x= 0.005, 0.04, 0.08, 0.20, and 0.25). The crystal structure, microstructure, dielectric and ferroelectric properties of samples were investigated by XRD, Raman Spectroscopy, Electrical Measurements and SEM. X-ray diffraction results clearly indicated that when x ≥ 0.25 was prepared; the hexagonal phase Ba8Ti3Nb4O24 appeared. Electrical measurements at 1 kHz were carried out and several pellets were made, the relative permittivity was calculated. The dielectric constant of the pristine BaTiO3 is about 7000, and the Curie temperature is ≈120°C at room temperature, decreasing to 90°C with Nb5+ addition (x = 0.005).

Preparation and Characterizations of Novel Near Room-Temperature Driven Fe/Sr2Bi2O5 Thermocatalyst

Materials Science Forum ◽

10.4028/www.scientific.net/msf.804.63 ◽

2014 ◽

Vol 804 ◽

pp. 63-66

Author(s):

Pei Wu ◽

Xue Gang Luo ◽

Xiao Yan Lin ◽

Ke Li

Keyword(s):

Room Temperature ◽

Negative Temperature Coefficient ◽

Removal Rate ◽

Negative Temperature ◽

X Ray Diffraction ◽

Total Removal ◽

Solid State Method ◽

X Ray ◽

Molar Percent

In this study, room-temperature driven thermocatalyst (Fe/Sr2Bi2O5 powder) with negative temperature coefficient resistor (NTC) characteristics was prepared by conventional solid state method at various temperatures. Fe/Sr2Bi2O5 powder was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy EDS. The results indicate that Fe/Sr2Bi2O5 powder was prepared and the Fe has been doped successfully in Sr2Bi2O5. The thermocatalyst powder obtained a particular and stable crystal style, meanwhile, besides, well distributed size and rough surface were also found in regard to the thermocatalyst above. On the other hand, the thermocatalyst reactions show that Fe/Sr2Bi2O5 powder has highest removal rate of degradation under the 0.75% (molar percent) content of Fe at 750 oC. The total removal rate of degradation arrives at 93.8% after 3h at 50 oC. Hence, Fe/Sr2Bi2O5 powder may be a potential thermocatalyst at room-temperature for wastewater treatment in the future.

Research on Preparation and Properties of Magnetic Abrasive by Conventional Solid-State Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.416.553 ◽

2009 ◽

Vol 416 ◽

pp. 553-557 ◽

Cited By ~ 2

Author(s):

Zeng Dian Zhao ◽

Yu Hong Huang ◽

Yu Gang Zhao ◽

Xian Jin Yu

Keyword(s):

Electron Microscope ◽

High Temperature ◽

Energy Dispersive Spectrometer ◽

Ferromagnetic Phase ◽

X Ray Diffraction ◽

Solid State Method ◽

X Ray ◽

State Method ◽

Scanning Electron

The silicon-coated iron powder was evenly mixed with corundum powder and high temperature binder. After tabletting and sintering, followed by crushing and screening, the magnetic abrasive with a certain size was obtained. Scanning electron microscope (SEM), Energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were respectively used to characterize the morphology, elemental composition and the crystalloid structures of magnetic abrasive. The ferromagnetic phase and abrasive phase were combined firmly. The magnetic abrasive prepared showed a good grinding ability, whose durable time was up to 24 min. Irregular particles was obtained by smashing the magnetic abrasive, mainly composed of Al2O3, Fe2O3, α-Fe, AlFeO3, (Al, Fe)7BO3(SiO4)3O3.

Structural, Dielectric and Electrical Properties of Fe Doped La0.7Ba0.3MnO3Solid Solutions for Cathode Materials

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.c6011.098319 ◽

2019 ◽

Vol 8 (3) ◽

pp. 7313-7317

Keyword(s):

Electron Microscopy ◽

Electrical Conductivity ◽

Single Phase ◽

X Ray Diffraction ◽

Solid State Method ◽

X Ray ◽

Density Values ◽

State Method ◽

Scanning Electron

The solid solutions of (La0.7Ba0.3)(FexMn1-x )O3 where x = 0.1 - 0.5 ceramics were synthesized by conventional solid-state method. The structural analysis was done by X-Ray diffraction technique and the results have revealed that all the samples were crystallized into a single phase. The surface morphology was done by Scanning Electron Microscopy and the micrographs clearly indicate decreased grain size with the increasing Fe - concentration. The density of the prepared samples was done using Archimedes principle and the density values were found to be in decreasing order, which is well in agreement with the microstructure relationship. The dielectric and impedance properties have been studied at different ranges of frequency and temperature. The electrical conductivity values were found to be greater than 100 Scm-1 , which suggests it to suitable cathode material of SOFCs

Tuning the Microwave Dielectric Properties of Nd0.96Yb0.04(Mg0.5Sn0.5)O3 by Introducing Ca0.8Sr0.2TiO3

10.4028/www.scientific.net/amr.1119.451 ◽

2015 ◽

Vol 1119 ◽

pp. 451-455

Author(s):

Yih Chien Chen ◽

Chih Hung Li ◽

Hua Xian Liu ◽

Jing Yu Fu

Keyword(s):

Dielectric Properties ◽

Sintering Temperature ◽

Microwave Dielectric Properties ◽

X Ray Diffraction ◽

Ceramic System ◽

Solid State Method ◽

X Ray ◽

Microwave Dielectric ◽

Diffraction Patterns

The influence of sintering temperature on the microwave dielectric properties and microstructure of the (1-y)Nd0.96Yb0.04(Mg0.5Sn0.5)O3-yCa0.8Sr0.2TiO3 ceramic system were investigated with a view to their application in microwave devices. The (1-y)Nd0.96Yb0.04(Mg0.5Sn0.5)O3-yCa0.8Sr0.2TiO3 ceramic systems were prepared using the conventional solid-state method. The X-ray diffraction patterns of the (1-y)Nd0.96Yb0.04(Mg0.5Sn0.5)O3-yCa0.8Sr0.2TiO3 ceramic system shifted to higher angle as y increased. A dielectric constant of 38.2, a quality factor (Q×f) of 53,500 GHz, and a temperature coefficient of resonant frequency of-3 ppm/°Cwere obtained when the 0.4 Nd0.96Yb0.04(Mg0.5Sn0.5)O3–0.6Ca0.8Sr0.2TiO3 ceramic system was sintered at 1600 °C for 4h.

Phase Structure and Piezoelectric Properties of (K0.5Nb0.5)NbO3 - CaZrO3 Ceramics

10.4028/www.scientific.net/amr.936.149 ◽

2014 ◽

Vol 936 ◽

pp. 149-153 ◽

Cited By ~ 1

Author(s):

Pyo Chun Myoung

Keyword(s):

Piezoelectric Properties ◽

Intermediate Phase ◽

Lattice Parameter ◽

X Ray Diffraction ◽

Solid State Method ◽

X Ray ◽

Maximum Value ◽

Monoclinic Distortion ◽

Distortion Angle

Lead-free piezoelectric ceramics of (1-x)(K0.5Na0.5)NbO3-xCaZrO3(abbreviated as KNN-CZ,x= 0 ~ 0.04) were synthesized by the conventional solid state method. Their phase structures and piezoelectric properties were investigated with x-ray diffraction (XRD), Scanning Electron Microscope (SEM), d33meter and Impedance Analyzer. KNN-CZ samples exhibit only pure perovskite phases with a small monoclinic distortion. It was observed that the lattice parameter b has a maximum atx= 0.02 but the monoclinic distortion angle β shows a minimum at the same composition. From the dependence of the lattice parameters (a, b, c, β) and cell volume on the content of CZ, it is considered that the intermediate phase transition exists near atx= 0.02. Piezoelectric properties show the maximum value of d33 = 121 pC/N and kp = 0.35 for the sample withx= 0.02, which seems to be due to the co-existence of the two different phases.

Rhombohedral-Orthorhombic Phase Transition Induced Enhancement on the Electrical Behavior of (K0.5Na0.5)NbO3-BiScO3-BiCoO3 Lead-free Piezoelectric Ceramics

MRS Proceedings ◽

10.1557/opl.2012.1134 ◽

2012 ◽

Vol 1397 ◽

Author(s):

Wenjuan Wu ◽

Dingquan Xiao ◽

Jiagang Wu ◽

Jing Li ◽

Wenfeng Liang ◽

...

Keyword(s):

Phase Transition ◽

Electrical Properties ◽

Room Temperature ◽

Composition Range ◽

Orthorhombic Phase ◽

Piezoelectric Ceramics ◽

Relaxor Behavior ◽

Electrical Behavior ◽

Solid State Method ◽

Conventional Solid State Method

ABSTRACT(1-x)K0.5Na0.5NbO3-x(0.97BiScO3-0.03BiCoO3) (KNN-xBSC) piezoelectric ceramics were prepared by the conventional solid-state method, and effects of the BSC addition on the phase structure, relaxor behavior, and electrical properties of KNN ceramics were systematically investigated. The rhombohedral to orthorhombic phase transition around room temperature was identified for the KNN-xBSC ceramics in the composition range of 0.015≤ x ≤0.0175, and improved electrical properties (d33∼205 pC/N, kp∼0.43, εr∼1315, and tan δ∼0.054) were observed for the ceramic with x=0.015 because of the involvement of such a phase transition at room temperature. Moreover, a relaxor ferroelectric behavior is demonstrated for these KNN-xBSC ceramics because of a more complex occupation of A and B sites in the ABO3 perovskite structure, together with a weak ferromagnetic order at room temperature.