Interface-Engineered ZIF-8-Derived ZnO@C/Bi/Bi2MoO6 Heterojunctions for Boosting Photo-Fenton-like Performance

In this work, a novel ZnO@C/Bi/Bi2MoO6 heterojunction is synthesized by assembling bismuth molybdate (Bi2MoO6) and ZIF-8-derived ZnO@C through a hydrothermal method for enhancing the photo-Fenton-like performance, where a tight interface contact is efficiently formed. The heterojunction not only improves the harvesting ability to visible light, but also promotes the separation and transfer of photogenerated electrons and holes. As a result, BZ400-2 achieves 69.8% degradation of tetracycline (TC) within 90 min under visible light irradiation (300 W Xe lamp; λ > 420 nm), with an apparent pseudo-first-order rate constant of 0.01081 min−1. Meanwhile, radical quenching experiments and ESR measurements confirm the involvement of·O2−, 1O2 and ·OH in the reaction system. Furthermore, the results of DFT theory demonstrate that the phenolic hydroxyl, ketone, and dimethylamine groups of tetracycline hydrochloride are more susceptible to free radical attack. Furthermore, the QSAR-based toxicity predictions suggest that most of the identified degradation intermediates exhibit lower acute toxicity than TC.