Large dipole moment induced efficient bismuth chromate photocatalysts for wide-spectrum driven water oxidation and complete mineralization of pollutants

Abstract

Herein, a wide-spectrum (∼678 nm) responsive Bi8(CrO4)O11 photocatalyst with a theoretical solar spectrum efficiency of 42.0% was successfully constructed. Bi8(CrO4)O11 showed highly efficient and stable photocatalytic water oxidation activity with a notable apparent quantum efficiency of 2.87% (420 nm), superior to many reported wide-spectrum driven photocatalysts. Most remarkably, its strong oxidation ability also enables the simultaneous degradation and complete mineralization for phenol, and its excellent performance is about 23.0 and 2.9 times higher than CdS and P25-TiO2, respectively. Its high activity is ascribed to the giant internal electric field induced by its large crystal dipole, which accelerates the rapid separation of photogenerated electron-hole pairs. Briefly, the discovery of wide-spectrum bismuth chromate and the mechanism of exponentially enhanced photocatalytic performance by increasing the crystal dipole throw light on improving solar energy conversion.