Construction of a 2D/2D Crystalline Porous Materials Based S-Scheme Heterojunction for Efficient Photocatalytic H2 Production

Generally, the low electron-hole separation efficiency of covalent organic frameworks (COFs) prevents their catalytic performance from reaching satisfactory results. For this reason, the creation of heterojunctions is considered an effective strategy but usually suffers from dimensional mismatch of the integrated material, even at the expense of its redox capacity. To overcome these difficulties, a novel 2D/2D S-scheme heterojunction between H2N-Cu-MOF (NCM) and TpPa-1-COF (TP1C) is successfully constructed for efficient photocatalytic H-2 production. The matching dimensions of two crystalline porous materials enables the integrated materials with abundant surface reactive sites, strong interaction and optimized electronic structure. Moreover, the combination of two crystalline porous materials can also form a S-scheme heterojunction, which can not only promote the separation of electron-hole pair, but also preserve the redox ability, thus remarkably boosting the catalytic competence. Consequently, the rate of optimal 20% NCM/TP1C in photocatalytic H-2 production reaches 4.19 mmol g(-1) h(-1), which is 46.5 times higher than that of bare NCM, and 22.1 folds over that of pure TP1C. This research offers an innovative perspective for the formation of S-scheme heterojunctions based on porous crystal materials for efficient solar energy utilization.