Compositional effects on structural, dielectric, ferroelectric and transport properties of Ba1−x(Bi0.5Li0.5)xTiO3 ceramics

Abstract

Single-phase Ba1−x(Bi0.5Li0.5)xTiO3 ceramics were prepared by conventional solid state reaction method, which shows tetragonal symmetry (space group P4mm). The crystal structure was refined by Rietveld analysis. The lattice parameters and satisfactory values of the Rietveld parameters, Rf, Rwp and RBragg were calculated by using X-ray diffraction data. The average grain size was found to lie in the range of 350 nm–720 nm as calculated by linear intercept method in Field Effect Scanning Electron Micrographs. As the (Bi0.5Li0.5)2+ content increases, the curie temperature of Ba1−x(Bi0.5Li0.5)xTiO3 ceramics was found to increase. The remnant polarization (2Pr) increases monotonously as the (Bi0.5Li0.5)2+ content increases and the highest value of 2Pr (=18.6 μC cm−2) and 2Ec (=15.37 kV cm−1) were obtained for x = 0.08 of (Bi0.5Li0.5)2+. FT-IR spectra show broad absorption bands corresponding to the metal oxygen bond. Complex impedance plots of Ba1−x(Bi0.5Li0.5)xTiO3 ceramics exhibit two semicircular arcs which are explained by the grain and grain boundary effect of the bulk ceramics.