MOF-templated core–shell CoSx@BiOBr Z-type heterojunction degradation of multiple antibiotics

Abstract

Hollow dodecahedral amorphous CoSx was prepared by solvothermal method using ZIF-67 as a sacrificial template, and then BiOBr nanosheets was grown on the surface of CoSx by in-situ growth method to form a CoSx@BiOBr Z-type heterojunction. This special hollow core–shell structure and oxygen vacancies work together, not only can promote the absorption of visible light, increase the specific surface area, improve the surface active sites, but also make the photogenerated electrons and holes easier to separate and migrate. Therefore, CoSx@BiOBr-5 showed excellent degradation effect on three antibiotics, namely carbamazepine, sulfamethoxazole and tetracycline hydrochloride. Furthermore, the possible catalytic mechanism of CoSx@BiOBr-5 was analyzed by quenching experiments and electrochemical characterization. The stable catalytic activity of CoSx@BiOBr-5 in harsh environments was confirmed by different initial pH, inorganic salt and cycling experiments. Therefore, the heterojunction CoSx@BiOBr-5 proposed in this study is a reusable, low-cost, and efficient catalyst for practical treatment of pollutant degradation.