Dielectric and electrical properties of Na_(2)Pb_(2)La_(2)W_(2)Ti_(4)Ta_(4)O_(30) electroceramics

查看全文 作　　者：[1]P.R.DAS;[2]S.BEHERA;[1]R.PADHEE;[3]P.NAYAK;[1]R.N.P.CHOUDHARY 机构地区：[1]Department of Physics,Institute of Technical Education&Research,Siksha‘O’Anusandhan University,Bhubaneswar-751030,Odisha,India;[2]Department of Physics,Hi-tech College Engineering,Bhubaneswar-75102,Odisha,India;[3]School of Physics,Sambalpur University,Jyoti Vihar,Burla-768019,Odisha,India 出　　处：《Journal of Advanced Ceramics》索引2012年第1卷第3期,共9页 摘　　要：The polycrystalline sample of complex tungsten-bronze type compound(Na_(2)Pb_(2)La_(2)W_(2)Ti_(4)Ta_(4)O_(30))was prepared by a high-temperature solid-state reaction technique.Room temperature preliminary structural study using X-ray diffraction(XRD)data exhibits the formation of a single-phase new compound.The SEM micrograph of the compound exhibits non uniform rectangular grains distributed throughout the sample surface.Detailed studies of dielectric parameters(εr,tanδ)as a function of temperature and frequency,and P-E hysteresis(spontaneous polarization)confirmed the existence of ferroelectricity in the material.Complex impedance spectroscopy analysis,carried out as a function of frequency at different temperatures,established a correlation between the microstructure and electrical properties of the material.The electrical relaxation process occurring in the material is temperature dependent.The activation energy found from the Arrhenius plot that the conduction process in the material is of mixed type.The nature of frequency dependence of ac conductivity suggests that the material obeys Jonscher’s universal power law. 关 键 词：electronic material FERROELECTRICITY XRD electrical conductivity