Construction of a flower-like S-scheme Bi2WO6/BiOCl nano-heterojunction with enhanced visible-light photocatalytic properties
Abstract
A novel flower-like S-scheme Bi2WO6/BiOCl nano-heterojunction is successfully fabricated by a simple one-pot hydrothermal method. With the construction of the flower-like structure and S-scheme heterojunction, the Bi2WO6/BiOCl-3 nano-heterojunction displays an excellent photocatalytic activity with a 98.6% degradation rate for rhodamine B (RhB) solution under visible light illumination, which is 2.51 and 2.91 times higher than those of Bi2WO6 and BiOCl catalysts, respectively. In order to interpret the photocatalytic process, pure Bi2WO6 and BiOCl are investigated by optical and electrochemical measurements, which obtained the band gap of Bi2WO6 (2.92 eV) and BiOCl (3.35 eV), the conduction band potential (0.07 eV) of the n-type semiconductor Bi2WO6 and the valence band potential (0.34 eV) of p-type semiconductor BiOCl. According to the radical species trapping experiments, a probable photocatalytic mechanism is discussed in detail. For the development and design of S-scheme heterojunction photocatalysts in wastewater treatment, the Bi2WO6/BiOCl nano-heterojunction is a promising photocatalytic material.