A CuI Cluster‐Based Covalent Metal‐Organic Framework as a Photocatalyst for Efficient Visible‐Light‐Driven Reduction of CO2

Abstract The application of solar energy to convert CO 2 into high‐value chemicals and fuels has been considered a highly desirable approach to relieving the greenhouse effect and energy crisis. However, the exploration of appropriate photocatalysts remains a major challenge. Combining the respective advantages of covalent organic frameworks and metal−organic frameworks to construct covalent metal−organic frameworks (CMOFs) can be a valid strategy to provide efficient, reliable, and eco‐friendly photocatalysts. In this study, a Cu I cluster‐based CMOF (JNM‐2) is used as a photocatalyst for CO 2 photoreduction under visible‐light irradiation. JNM‐2 exhibits remarkable efficiency in photocatalytic CO 2 reduction with high production rates of HCOOH (9019 μmol g −1 h −1 ) and CO (835 μmol g −1 h −1 ). The active center, reaction intermediates, and product generation pathways are elucidated by in situ DRIFTS and DFT calculations. This work demonstrates the tremendous possibilities of CMOFs as photocatalysts for CO 2 reduction and provides profound insights into the mechanism of CO 2 conversion into HCOOH/CO by using a molecularly accurate structural model.