Fabrication of CdS/BiOI heterostructure with enhanced photocatalytic performance under visible-light irradiation

A series of CdS/BiOI (Cd-Bi) heterojunction photocatalysts with different CdS loading were prepared by a simple ultrasonic-assisted calcination method. All samples were characterized by XRD (X-ray powder diffraction), N2 physisorption isotherms and other techniques to investigate the impact of heterostructure. Among them, Cd-Bi-0.30 (0.30 represents the mass ratio of CdS to BiOI) shows a significantly improved photocatalytic oxidation capacity under LED lamp irradiation due to heterojunction construction and a suitable additive amount, leading to photogenerated electron-hole pairs separation promoting, so that more charge carriers can participate in the photoreaction. Finally, the mechanism of photocatalytic oxidation of Hg0 by the as-prepared CdS/BiOI photocatalyst was discussed in detail.