Phase character and structural anomaly of Bi_4Ti_3O_12 nanoparticles prepared by chemical coprecipitation

摘要

Nanoparticles of Bi_4Ti_3O_12 have been prepared by chemical coprecipitation. The phase structure was investigated by X-ray diffraction (XRD) and refined using the Rietveld method. Orthorhombic Bi_4Ti_3O_12 particles were obtained after heating at 700 and 800℃; however, for the particles calcined at 500-650℃, the results suggested the presence of a high-temperature tetragonal phase at room temperature. This structural anomaly was further confirmed by differential thermal analysis (DTA).