The 2D/2D p–n heterojunction of ZnCoMOF/g‐C 3 N 4 with enhanced photocatalytic hydrogen evolution under visible light irradiation

Construction of heterojunction is an important means to improve photocatalytic performance. In this work, 2D/2D ZnCoMOF/g‐C 3 N 4 heterojunction photocatalyst was designed and successfully obtained by electrostatic assembly. Combing the complementary advantages of two‐dimensional MOFs and g‐C 3 N 4 , the obtained composite samples showed superior photocatalytic hydrogen evolution performance. By optimizing the composite ratios and metal centers of MOFs, g‐C 3 N 4 composited with 5 wt% bimetallic ZnCoMOF (CNZnCo5) was obtained and exhibited the highest hydrogen production rate of 1,040.1 μmol/g/h, which was 33.2 times of bulk g‐C 3 N 4 and 3.5 times of 2D g‐C 3 N 4 . Besides, the reasons for the improvement of photocatalytic hydrogen production were analyzed by a series of optical and photoelectrochemical measurements. The formation of ZnCoMOF/g‐C 3 N 4 p–n heterojunction enhanced the absorption of visible light, and the 2D/2D heterojunction shortened the distance of charges migration to the surface, thus accelerating the charges separation and transfer. This work may provide some insights into design and preparation of specific 2D/2D heterojunction with enhanced photocatalytic performance.