Fabrication of CuS-modified inverse opal g-C3N4 photocatalyst with enhanced performance of photocatalytic reduction of CO2

Abstract As a greenhouse gas, CO2 is also a rich carbon resource. Using sunlight to reduce CO2 to usable substances through photocatalysis can alleviate the greenhouse effect and realize energy recycling. Herein, CuS nanoparticles are grown in situ on the surface of inverse opal g-C3N4 by a one-step hydrothermal method. The inverse opal structure can increase the specific surface area of the material, and CuS can be used as the cocatalyst to accept photo-generated electrons on the conduction band of g-C3N4, thereby promoting the separation and transfer of photo-generated charges. And the interfacial charge transfer mechanism of CuS further improves the separation efficiency of photogenerated electrons and holes. The photocatalytic reduction of CO2 activity of the prepared catalyst is greatly improved. The CO yield reaches 13.24 μmol g−1 h−1. A new strategy is provided to develop artificial photosynthesis for reduction of CO2.