Hydrothermal synthesis of novel BiFeO3/BiVO4 heterojunctions with enhanced photocatalytic activities under visible light irradiation

Abstract

BiFeO₃/BiVO₄ heterojunction photocatalysts were synthesized by a hydrothermal method. The structures and optical properties of the as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field-emission transmission electron microscopy (TEM), and UV-vis absorption spectroscopy, respectively. The photocatalytic performances of the as-synthesized products were thoroughly evaluated via the degradation of Rhodamine B (RhB) under visible light irradiation. Experimental results showed that 50% mole ratio of BiFeO₃ to BiFeO₃/BiVO₄ photocatalyst exhibited the highest photocatalytic activity compared to other as-prepared products. Moreover, the stability of the as-prepared photocatalyst during the photocatalytic process was also investigated. In addition, the enhanced photocatalytic activity of the as-prepared products could be probably ascribed to the high separation efficiency of the photogenerated electron–hole pairs generated at the heterojunction between BiFeO₃ and BiVO₄.