Controllable Microwave Hydrothermal Synthesis of Bismuth Ferrites and Photocatalytic Characterization

摘要

The process, by which three kinds of bismuth ferrites (BiFeO_3, Bi_(25)FeO_(40), and Bi_(25)FeO_(40)-BiFeO_3) were synthesized for 1 h through a microwave hydrothermal method by changing the KOH concentration and the temperature, is summarized in this article. The as-prepared bismuth ferrite powders were characterized by the X-ray diffraction, the field emission scanning electron microscopy, and the transmission electron microscope, and the band gaps, specific surface areas, photocatalytic and magnetic properties were explored as well. The results showed that the degradation degree of methyl orange using BiFeO_3, Bi_(25)FeO_(40), and Bi_(25)FeO_(40)-BiFeO_3 as catalyst were 35%, 52%, and 90% at 2 h, respectively, and the magnetizations of the three powders were 0.07, 3.17, and 0.55 emu/g, respectively. This indicated that the porous cubic Bi_(25)FeO_(40)-BiFeO_3 powder has the best photocatalytic property of the three, making it useful as a new type of photocatalytic material which can be easily recycled by magnetic separation.