2D–2D SnS₂/Covalent Organic Framework Heterojunction Photocatalysts for Highly Enhanced Solar-Driven Hydrogen Evolution without Cocatalysts

Abstract

Covalent organic frameworks (COFs) are a category of promising materials in the field of solar-driven hydrogen (H2) evolution, but their applications are limited by the speedy recombination of photoinduced charge carriers and the absorption of marginal visible light. Herein, a 2D–2D SnS2/TpPa-1-COF heterojunction photocatalyst was prepared via a one-step hydrothermal route to relieve the abovementioned shortcomings. The results show that the obtained 2D–2D SnS2/TpPa-1-COF heterojunctions not only speed up the separation of photogenerated charge carriers but also facilitate the H2 production kinetics and expand the range of visible light response to orange light (600 nm). Especially, the maximum photocatalytic H2 production rate of the 2D–2D SnS2/TpPa-1-COF heterojunction without the addition of cocatalyst Pt reaches 37.11 μmol h–1, which is 21.7-fold and 2-fold higher than those of individual TpPa-1-COF and 3 wt % Pt/TpPa-1-COF, respectively. This work indicates that the synthesis of cheap COF-based photocatalysts for high-efficiency solar energy utilization is a feasible approach to boost the photocatalytic H2 performance.