Effect of Sr-substitution on structural, dielectric and impedance characteristics of MPB-PZT Effect of Sr-substitution on structural, dielectric and impedance characteristics of MPB-PZT
1Department of Physics, Rajiv Gandhi University of knowledge Technologies, RK Valley 516330, India
2Department of Metallurgical & Materials Engineering, Rajiv Gandhi University of Knowledge Technologies,RK Valley 516330, India
3Department of Physics, Indian Institute of Technology, Kharagpur 721302, India
4Department of Physics, Bundelkhand University, Jhansi (U.P.) 284002, India
5Department of Physics, Institute of Technical Education and Research SOA University, Bhubaneswar 751 030, India
Adv. Mater. Lett., 2016, 7 (11), pp 918-925
Publication Date (Web): Oct 01, 2016
Copyright © IAAM-VBRI Press
The polycrystalline sample of Sr-modified Pb(Zr0.5Ti0.5)O3 (i.e. Pb1-xSrx(Zr0.5Ti0.5)O3 (x = 0.05-0.15)) ceramics were synthesized (close to morph-tropic phase boundary) by a cost effective (solid state reaction) method. Detailed investigation of structural phase transition was carried out using room temperature X-ray diffraction data adopting Rietveld refinement technique. The coexistence of two crystal phases (i.e., tetragonal (P4mm) and rhombohedral (R3c) for x = 0.05, and single tetragonal (P4mm) phase for x = 0.1, 0.15) were observed. Elemental analysis, grain shape and size distribution were studied using scanning electron microscope. The decrease in grain size on increasing Sr2+ concentration was also observed. Detailed analysis of temperature and frequency dependence of dielectric exhibits the increase in dielectric permittivity as function of Sr2+ concentration at room temperature. Beside this, the greatly reduced Curie (TC) temperature and broadening of dielectric maxima as function of increasing Sr2+ concentration in PZT was observed. The multiple relaxation processes associated with grain, grain boundaries and interfacial polarization was noted for x=0.05 and x=0.10 to analyze the Nyquist plots. The dominant of grain boundary resistance with increasing in dopent concentration x=0.15 was observed.
Polycrystalline, dielectric permittivity, rietveld refinement technique.