Synthesis and dielectric properties of BiFeO3 derived from molten salt method

BiFeO3 powder was synthesized in NaCl media at temperature range from 700 to 800 °C, using Bi2O3 and Fe2O3 as raw materials. Effects of calcining temperature and salt ratios on the synthesis of BiFeO3 powder had been investigated. It was found that NaCl effectively promoted the formation of BiFeO3. Almost pure BiFeO3 phase with a very small amount of Bi2Fe4O9 phase was synthesized at 750 °C with salt weight ratios of 1:1. A large amount of BiFeO3 phase decomposed to Bi2Fe4O9 and Bi25FeO39 phase when the temperature was up to 800 °C. In the present method, the calcining temperature played an important role in the formation of BiFeO3 phase. BiFeO3 ceramics derived from molten salt method were prepared and exhibited the higher dielectric constant.