Progress in the Construction of Metal Oxide Heterojunctions and Their Application in Photocatalytic CO2 Reduction

China has put forward the strategic goals o f "carbon emissions peak" in 2030 and "carbon neutrality" in 2060. It is of great significance to convert CO2 into high-value-added chemical products and liquid fuels,which can reduce the dependence on coal,oil and other traditional resources while achieving carbon emission reduction. Photocatalytic CO2 reduction is a very important way,and the design and preparation of efficient photocatalysts for CO2 reduction are the key. Well-defined heterojunction structures between metals and semiconductors or semi-conductors with matching electronic band structures can effectively promote charge transfer and inhibit the recombi. nation of photogenerated electrons and holes,thus improving the photocatalytic performance. This review focuses on the recent progress of oxide-based heterostructures for photocatalytic CO2 reduction,and systematically summarizes the types and components of the formation of heterostructures,and expounds the internal mechanism of improving the performance of CO2 photocatalysis. Furthermore,the direction of research in this field is also prospected.