Bimetallic (Cu, Zn) ZIF-derived S-scheme heterojunction for efficient remediation of aqueous pollutants in visible light/peroxymonosulfate system

The design of suitable catalyst is the bottleneck in the photo-assisted Fenton-like reaction system. Here we constructed a S-scheme heterojunction consisted of CuO and Cu doped ZnO using Cu-ZIF-8 as precursor. The as-prepared composite catalyst possesses outstanding catalytic activation performance and broad-spectrum degradation capacity. To clearly fit and describe the overall reaction, a pseudo-third-order kinetic model was developed based on the second-order peroxymonosulfate (PMS) consumption and first-order methylene blue removal. The catalyst/visible light/ PMS composite reaction system provides remarkable mineralization and anti-interference ability, and is environmental friendliness. The interaction of Cu/Zn bimetallic sites realized the effective utilization of PMS, accelerated the PMS activation and promoted the formation of the highly oxidative SO5•−. Overall, this work provides new systematic insights on PMS activation by Cu/Zn bimetallic oxide S-scheme heterojunction and is of significance for sewage purification. [Display omitted] •A S-scheme heterojunction was constructed by using Cu-ZIF-8 as precursor.•The as-prepared CuZnO-3 exhibited superior catalytic activation capability.•A pseudo-third-order kinetic model was developed involving the reacted MB and PMS.•The CuZnO-3/vis/PMS reaction system was evaluated to be environmentally friendly.•The catalytic activation mechanism of Cu/Zn bimetallic sites was proposed.