Bi2S3-Nanowire-Sensitized BiVO4Sheets for Enhanced Visible-Light Photoelectrochemical Activities

BiVO4is widely used for photoelectrochemistry and photocatalytic oxygen evolution under visible-light irradiation. To extend the range of visible-light absorption and reduce the recombination rate of photoexcited electrons and holes, a BiVO4sheet–Bi2S3nanowire heterostructure was fabricated through an easy in situ hydrothermal method. In this method, Bi2S3nanowires were uniformly coated onto the surface of BiVO4sheets. The heterostructure exhibits a wide visible-light absorption band ranging from 525 to 900 nm after coupling with Bi2S3nanowires. The BiVO4sheet–Bi2S3nanowire heterostructures were used for photoelectrochemical measurements and exhibited higher photocurrent intensity than those of BiVO4sheets and BiVO4particle–Bi2S3under visible-light irradiation. The optimized amount of Bi2S3in the heterostructure was approximately 2.4 at. %. The remarkable enhancements in the photoelectrochemical property were attributed mainly to the solid sensitization of Bi2S3nanowires providing a number of photoexcited electrons, shortening transport distance in BiVO4sheets, smoothening migration along Bi2S3nanowires, and enhancing the synergistic effect between BiVO4and Bi2S3.