Synthesis of SrBi2Ta2O9 nanocrystalline powder by a modified sol–gel process using bismuth subnitrate as bismuth source

Abstract Steady sol and gel of SrBi 2 Ta 2 O 9 (SBT) was prepared using pentaethoxy tantalum, strontium acetate, and bismuth subnitrate as raw materials and ethylene glycol as a solvent. After a dried gel was pretreated at 350 °C for 30 min and then it was calcined at 800 °C for 1 h, the perovskite phase SBT ferroelectric powder was obtained. The formation mechanism of the sol and gel was proposed. In the baking process perovskite phase SBT forms via a reaction between bismuth oxide (cubic phase) and strontium tantalate (orthorhombic phase).