BiFeO_3 Powders Synthesized by Different Sol-gel Methods

摘要

The multiferroic BiFeO_3 powders with perovskite structure were synthesized by sol-gel auto-combustion and conventional sol-gel methods, respectively. As-prepared powders were characterized by XRD, SEM and VSM techniques to investigate phase structure, microstructure and magnetic properties. The results show that the pure phase BiFeO_3 powders are obtained successfully by sol-gel auto-combustion after calcining at 650°C for 2h and leaching by HNO_3. Compared with conventional sol-gel method which got pure phase BiFeO_3 powders at 800°C for 3h, the sol-gel auto-combustion technique can get more pure powders at low temperature, short time and low cost. The particle sizes of the BiFeO_3 powders are smaller and well distributed by the sol-gel auto-combustion method than that of the conventional sol-gel method. Furthermore, the magnetic properties at room temperature prepared by the sol-gel auto-combustion methods are significant higher than that of conventional sol-gel method.