Microwave hydrothermal synthesis of perovskite BiFeO3 nanoparticles: An insight into the phase purity during the microwave heating process

In this work, a facile method for the synthesis of pure phase BiFeO3 (BFO) nanoparticles with the microwave assistance was reported. BFO nanoparticles with high pure phase can be prepared in 20 min, which is much shorter than that of the traditional hydrothermal methods. The effect of microwave heating time on the phase purity of obtained samples was investigated in detail by using X-ray diffraction (XRD). An interesting phenomenon was observed that the pervoskite-type BFO with pure phase periodically appeared during the microwave heating process. The investigation of the magnetic properties of prepared samples also revealed the periodical formation of the pure phase BFO. The sample with a microwave heating time of 20 min shows a magnetization of 1.05 emu g−1 which is in accordance with the reported value. -- Highlights: ► Pure phase BiFeO3 nanoparticles were prepared with microwave assistance in 20 min ► Pure phase BiFeO3 formed, decomposed and reformed periodically during the microwave heating process. ► The special heating mechanism of microwave causes this phenomenon. ► The evolution of the magnetization testified the periodical formation of the pure phase BiFeO3.