Novel visible-light-driven CdIn2S4/mesoporous g-C3N4 hybrids for efficient photocatalytic reduction of CO2 to methanol

Photocatalytic conversion of CO 2 into hydrocarbon fuels using semiconductor photocatalysts has attracted great attention, which is considered as a promising approach to resolve the energy shortage and greenhouse effect. In this work, ordered mesoporous g-C 3 N 4 (mpg-C 3 N 4 ) nanosheets supported CdIn 2 S 4 nanocomposites were successfully fabricated by a hard-template combinated with hydrothermal method. The hybrids showed highly efficient photocatalytic activities for the reduction of CO 2 to CH 3 OH under visible-light irradiation. The optimized CdIn 2 S 4 /mpg-C 3 N 4 photocatalyst exhibited a high CH 3 OH-production rate of 42.7   μmol   g −1   h −1 at a mpg-C 3 N 4 content of 20   wt%. This rate was 1.8 times higher than that of pure CdIn 2 S 4 . The significant enhancement of photocatalystic activity was mainly ascribed to the increased CO 2 adsorption capacity and the improved separation and transfer of photogenerated electron-hole pairs at the intimate interface of CdIn 2 S 4 /mpg-C 3 N 4 heterojunctions. Furthermore, the hybrid photocatalysts displayed excellent stability under visible-light. A possible mechanism of enhanced photocatalytic activity of CdIn 2 S 4 /mpg-C 3 N 4 composite on photocatalytic reduction of CO 2 was also proposed. This work may provide some useful information for the future design and practical application of multifunctional hybrid photocatalysts in photocatalytic reduction of CO 2 .