Enhanced visible-light photocatalytic CO2 reduction performance of ZnIn2S4 microspheres by using CeO2 as cocatalyst

ZnIn2S4 flower-like microspheres decorated with CeO2 as cocatalyst have been successfully fabricated through a microwave-assisted hydrothermal method for visible-light carbon dioxide (CO2) photoreduction to produce methanol (CH3OH). All the composite photocatalysts exhibited a more excellent photocatalytic performance than bare CeO2 and ZIS, and reached the highest with a CH3OH evolution rate of 0.542 mu mol g(-1) h(-1) when the content of CeO2 was 5 wt%. In the composites, the CeO2 with oxygen vacancies acted as a significant cocatalyst to efficiently trap the photogenerated electrons from ZIS and thus boosted the separation of photoinduced charge carriers, while the unique 3D structure of ZIS made it with a relatively large specific area, which could provide abundant active reaction sites and render the reactants and products diffuse more easily. This study verified the CeO2 as one of the ideal cocatalyst candidates for ZnIn2S4 in the application of photocatalytic CO2 reduction, and gave rise to an increasing interest in expanding potential applications of ZnIn2S4 based materials in the field of energy conversion.