Layered Heterostructures of Ultrathin Polymeric Carbon Nitride and ZnIn₂S₄ Nanosheets for Photocatalytic CO₂ Reduction

Abstract

Abstract The rational construction of heterostructures by using layered semiconductors with two‐dimensional (2D) nanosheet configurations is promising to improve the efficiency of CO 2 photoreduction. Herein, the fabrication of layered heterojunction photocatalysts (PCN/ZnIn 2 S 4 ) by in situ growth of 2D ZnIn 2 S 4 nanosheets on the surfaces of ultrathin polymeric carbon nitride (PCN) layers is presented for greatly enhanced CO 2 conversion with visible light. The solution‐processed self‐assembly strategy renders the building of uniform and intimate junctions between PCN layers and ZnIn 2 S 4 subunits, which remarkably accelerates the separation and transfer of photogenerated charge carriers. In addition, the layered composites can also promote CO 2 adsorption and strengthen the visible‐light absorption. Consequently, the optimized PCN/ZnIn 2 S 4 sheet‐shaped composite shows reinforced photoactivity for deoxygenative CO 2 conversion, affording a high CO‐production rate of 44.6 μmol h −1 , which is 223 times higher than that of the pristine PCN nanosheets. Moreover, the heterojunction photocatalyst also exhibits high stability during repeated runs for five cycles.