High Pressure and Temperature Synthesis of Bi-based Perovskite (Bi_0.5Na_0.5-xLi_x)TiO₃

Abstract

High-pressure synthesis of bismuth based perovskite (Bi_0.5Na_0.5-xLi)TiO₃ (BNLT) (=0.1, 0.15, 0.2, 0.25, 0.4, 0.5) was demonstrated. Single phase BNLTs with perovskite structure were successfully synthesized for x≤0.1 by the solid state reaction method. The solid phase reaction occurred in the pressure range of 6–10 GPa, and in the temperature range of 800–1200°C. Two thermal anomalies were observed in single phase perovskite BNLT(x=0.1) as well as (Bi,Na)TiO₃. The cusp like anomaly at 210°C was assigned to a rhombohedral-tetragonal structural phase transition. The finished products of x≥0.2 included three kinds of impurities, which were affected by the selection of starting materials.