Interfacial Charge Transfer between Silver Phosphate and W2N3 Induced by Nitrogen Vacancies Enhances Removal of β‐Lactam Antibiotics

Abstract Constructing heterojunctions has been demonstrated as an important approach to improve the catalytic performance of photocatalysts, but how to regulate the transfer and separation of photogenerated carriers at the interface is still a great challenge. Herein, W 2 N 3 ‐NV, a two‐dimensional transition metal nitride containing nitrogen vacancies, is synthesized by a molten salt‐assisted atmosphere calcination method. A novel composite photocatalyst Ag 3 PO 4 @W 2 N 3 ‐NV with good photocatalytic activity and photostability is prepared for the first time and applied to the efficient removal of β‐lactam antibiotics. The composite catalyst shows much superior photocatalytic degradation performance of penicillin and amoxicillin, and the apparent rate constant of which is 77.7 and 42.9 times than that of pure Ag 3 PO 4 , respectively. Experimental results and density functional theory calculations confirm that the presence of nitrogen vacancies can drive the formation of defects and dangling bonds on the W 2 N 3 ‐NV surface, which make it easy to combine with Ag 3 PO 4 and form new chemical bonds at the interface. The WO chemical bonds formed at the interface provide a fast transfer channel for the interfacial photogenerated charge, resulting in the boosted carriers transfer and separation ability of Ag 3 PO 4 @W 2 N 3 ‐NV composite. This study provides a new strategy for the interface engineering of highly efficient heterogeneous photocatalysts.