Phase transition of BaTiO3–Ba1-xPbxTiO3 composite particles prepared by the molten salt method

Abstract

BaTiO ₃ –Ba _1-x Pb _x TiO ₃ composite particles have been prepared by the molten salt reaction at 600 °C in the BaTiO ₃ –PbCl ₂ system. A coating of Ba _1-x Pb _x TiO ₃ on BaTiO ₃ was indicated by X-ray diffraction (XRD), high-temperature XRD (HTXRD) and energy-dispersive X-ray analysis (EDXA). Different particle sizes of BaTiO ₃ (0.1 µm and 0.5 µm) and molar ratios of PbCl ₂ /BaTiO ₃ (0.5 and 1.0) produced two sizes of composite particles, the larger particles having estimated x values of 0.5≤x≤0.8 and x≈0.9, and the smaller particles having x values of 0.4≤x≤1.0. The phase transition was followed by HTXRD and differential scanning calorimetry (DSC) measurements during heating and cooling. The results of dielectric measurements were used to provide an explanation of the phase transition in the composite particles.