One-pot fabrication of Cd_xZn_1-xS/ZnO nanohybrid using mixed sulfur sources for photocatalysis

Cd_xZn_1-xS/ZnO nanohybrids were fabricated by using mixed Na₂S and Na₂S₂O₃ as the sulfur source via a facile one-pot synthesis. Cd_xZn_1-xS/ZnO with x = 0.54, 0.58, 0.62, 0.68 and 0.75 was successfully tuned by altering the molar ratio of Na₂S and Na₂S₂O₃. Sole sulfur source Na₂S or Na₂S₂O₃ could only generate Cd_0.5Zn_0.5S or CdS/ZnO, respectively. The in-situ co-growth of Cd_xZn_1-xS and ZnO makes them combine penetratingly in Cd_xZn_1-xS/ZnO nanohybrids, giving them a highly intimate contact. The natural matched band-edge positions and highly intimate contacts between Cd_xZn_1-xS and ZnO are conductive to charge separation and transfer. Benefiting from the structural and compositional merits, the optimized Cd_xZn_1-xS/ZnO nanohybrid with sizes of about 5−8 nm exhibited outstanding performance for Cr(VI) reduction under visible-light illumination. The newly designed one-pot synthetic strategy in this work may provide a brand-new pathway in developing high-efficiency multi-component photocatalysts for practical use.