The modification of surface, size and shape of barium zirconate powder via salt flux

Abstract

The “top‐down” process via direct conversion of the micro (μm)‐to‐submicroscale (sub‐μm) particle was applied in this work by using eutectic chloride salts to prepare BaZrO3. The particle size at optimum condition could be decreased by more than 10 times from 2.1 ± 0.9 μm to 168 ± 23 nm without destroying the 1:1 of Ba:Zr stoichiometry. The uniform sub‐μm‐BaZrO3 powder was sintered in order to obtain ~98% dense ceramic at 1400°C/10 h, which is significantly lower than the 1650°C in normal cases. The microwave dielectric constant, tan δ, and quality factor were also determined. Furthermore, this method also was applied to lead‐free piezoelectric material in the 0.87BaTiO3–0.13BaZrO3–CaTiO3 (0.87BT–0.13BZ–CT) system. The particle size of 0.87BT–0.13BZ–CT was reduced greatly from >10 µm to 2.8 ± 0.4 µm. It can be proved that salt flux dissolution method enables high‐purity with uniform sub‐micro/nanometer powder production in one step by using simple laboratory equipment and low‐cost raw materials.