In Situ Synthesis of Bi0/Bi2MoO6/NH2-UiO-66 S-Scheme Heterojunction through Interfacial Regulation for Visible-Light-Driven Removal of Antibiotics from Wastewater

The rapid recombination of photogenerated carriers and high interfacial resistance severely limit the efficiency of photocatalytic wastewater treatment. Herein, an advanced interfacial-engineered S-scheme Bi0/Bi2MoO6/NH2-UiO-66 heterostructure photocatalyst was constructed by first fabricating a binary Bi2MoO6/NH2-UiO-66 S-scheme heterojunction photocatalyst, followed by the in situ growth of metallic Bi0 nanoparticles. An S-scheme mechanism successfully governs the fast spatial decoupling of photoinduced charge carriers. This efficient electron–hole segregation operates under the combined motivation stemming from a powerful internal electric field (IEF) alongside the low-resistance Ohmic contact established by metallic Bi0. At a catalyst dosage of 1.0 g/L and natural solution pH, the optimized photocatalyst achieved 96.58% degradation efficiency for 20 mg/L tetracycline hydrochloride (TCH), within 60 min of visible-light irradiation, and its photocatalytic activity was remarkably superior to those of single-component and binary catalysts. Furthermore, measurements utilizing liquid chromatography–mass spectrometry (LC-MS) techniques coupled with theoretical density functional theory (DFT) models accurately pinpointed reactive molecular targets, clarifying the intermediate decomposition routes of TCH. This research provides essential guidance toward engineering good plasmon-activated architectures intended for ecological wastewater remediation.