Enhanced photocatalytic activity by loading Zn0.5Cd0.5S quantum dots onto flower-like BiOI under visible light

Solar photocatalytic has evolved into a highly promising technology purification. In this study, S-type heterojunction photocatalyst comprising Zn0.5Cd0.5S (ZCS) and BiOI is successfully prepared with hydrothermal process. When ZCS accounts for 1%, the prepared Zn0.5Cd0.5S/BiOI exhibits superior photocatalytic behavior, with a degradation rate of Rhodamine B (RhB) reaching 99.2% under visible light for 75 minutes, and the reaction rate is 4.5 and 3.3 times higher than that of single ZCS and BiOI. The excellent photocatalytic property is related with the S-type heterojunction architecture, promoting the charge separation and suppressing carrier recombination. In the degradation process, O2– is the primary active ingredient, while OH and h+ assume a subordinate position. Furthermore, the composite has remarkable photocatalytic stability during the circulation, with over 90% RhB degradation maintained after four cycles. The current work offers a viable S-type heterojunction photocatalyst for the treatment of dyeing wastewater.