Hollow direct Z‒Scheme CdS/BiVO4 composite with boosted photocatalytic performance for RhB degradation and hydrogen production

Abstract

The hollow direct Z–scheme photocatalyst CdS/BiVO4 with tunable loading amount of CdS was successfully fabrication by means of hydrothermal method. The photocatalytic experiment results show that CdS/BiVO4 heterostructure possessed superior photocatalytic activity toward RhB degradation and water splitting in comparison with bare BiVO4 and CdS. Under UV–vis light irradiation, 94.7% of RhB (15 mg/L, 100 mL) was degraded and 197.2 mmol g−1 of hydrogen production rate was obtained in the present of CdS/BiVO4 with 25% CdS content within 1 h. Based on the density functional theory calculation, PL spectra testing and electrochemical analysis, it is found that the internal electric field established between BiVO4 and CdS greatly suppressed the combination of photoinduced carriers, prolonged the lifetime of electron–hole pairs and maintained sufficient redox reaction driving force for photocatalytic reaction, which endowed admirable photocatalytic performance to the CdS/BiVO4 heterostructure.