Preparation of CaZrO3 powders by a microwave-assisted molten salt method

Abstract

CaZrO3 powders were synthesized by a combined molten salt and microwave heating technique, i.e., microwaveassisted molten salt synthesis (MMSS) technique, using ZrO2 and CaCl2 as the main raw materials, and molten LiCl and Na2CO3 as a reaction medium. Phase pure CaZrO3 powders can be synthesized at 900°C for 3 h by using the MMSS method. This synthesis temperature was at least 100°C lower than that required by the conventional molten salt synthesis method. Microstructures and phase compositions of as-prepared CaZrO3 powders were examined by field emissionscanning electron microscopy (FESEM) and transmission electron microscope (TEM), revealing that the crystalline size of the as-prepared CaZrO3 powders was about 100300 nm, and the "template formation" mechanism played a dominant role in the synthesis process of MMSS.