In-situ fabrication of Z-scheme CdS/BiOCl heterojunctions with largely improved photocatalytic performance

Abstract

In order to meet the needs of practical applications, it is indispensable to exploit novel Z-scheme-based heterojunctions with enhanced separation efficiency of photo-induced carries and photocatalytic activity. In this work, a series of Z-scheme CdS/BiOCl heterojunctions were synthesized by a facile hydrothermal method. The as-prepared samples were characterized by a series of analytic technique. The photocatalytic properties of the as-prepared samples were evaluated using rhodamine B (RhB) as model pollutant. The results imply that the CdS/BiOCl heterojunctions exhibit much higher photocatalytic decay abilities than the bare BiOCl and CdS under simulated sunlight irradiation. The boosted photocatalytic activities can be ascribed to the Z-scheme of separation property of photo-generated electron-hole pairs. The capture experiments and electron spin-resonance (ESR) results certify that the h+ and O2− radicals are the predominant active free species in the photocatalytic reaction system. In light of all the experimental results, we proposed a Z-scheme to elaborate the improved photocatalytic decontamination ability of CdS/BiOCl heterojunctions toward RhB.