Preparation of CoS2/g-C3N4 composite catalyst and its application in 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 not only alleviate the increasingly serious greenhouse effect, but also is a promising method to achieve energy recycling to solve the problem of energy shortage. Herein, the CoS2 promoter was grown on g-C3N4 nanosheets by a simple in-situ growth method and the composite catalyst was applied for the photocatalytic reduction of CO2. In the catalyst, CoS2 nanoparticles were uniformly distributed on g-C3N4 nanosheets. The g-C3N4 nanosheet structure increased the specific surface area of the material, thereby facilitating the exposure of CoS2 sites. Moreover, as a non-precious metal promoter, CoS2 can replace some precious metal promoters to improve the separation efficiency of photo-generated charges in g-C3N4. The prepared catalyst exhibited an efficient and stable photocatalytic performance for reduction of CO2 and had a high selectivity for CO generation. This work provides a new idea for designing a low-cost and high-performance photocatalyst for photocatalytic reduction of CO2.