Synthesis of BaZrO3 by a solid-state reaction technique using nitrate precursors

High phase purity barium metazirconate powders have been synthesized from a modified solid-state reaction. Reactive powders consisting of submicron particles and narrow particle size distribution were obtained by heating a 1:1 molar mixture of barium nitrate and zirconyl nitrate at 800°C up to 8 h. Simultaneous thermal analysis (TG-DTA) assisted in elucidating the probable reaction pathways leading to the formation of the target compound in the BaO–ZrO2 system. Systematic structural and microstructural characterization on the green powders and the compacts sintered up to 1700°C were carried out. A two-stage sintering schedule consisting of a 6 h soak at 1600°C followed by slow heating up to 1700°C with no dwell, led to highly dense microstructural features.