The Roles of Polyoxometalates in Photocatalytic Reduction of CO2

Abstract As is well known, CO2 reduction reaction (CO2RR) by photocatalytic technology is a means with great promise to alleviate the crisis of energy and the environment. It is significantly critical to design and construct photocatalysts with high performance as catalysts in the core of the photocatalytic process. Recently, polyoxometalates (POMs) have aroused wide concern as CO2 photoreduction-related catalysts because they possess tunable compositions, thermal stability, redox and tailorable light-absorption abilities. This review has discussed the recent progress of POMs and POM-based photocatalysts for CO2 reduction focusing on the roles of POMs as photocatalysts, co-catalysts, photocatalytic hosts (photosensitizers), and multi-electron donors in systems of CO2 photoreduction, which can provide important guides for the design of high-efficiency photocatalysts. In the end, based on summarizing the previous work, we make a prospect to the future research direction, key challenges, and possible solutions in this field.