Photocatalytic reduction of CO2 to useful fuel has been identified as a promising strategy to address the energy and environmental issues.Development of well-defined photocatalysts toward CO2 reduction has attracted increasing interest to gain insight into the reactive mechanism.Herein,by post-synthetic ligand exchange,a bifunctional Re-based metal-organic framework (MOF)was successfully prepared.It not only serves as a photosensitizer but also acts as a catalyst for photochemical reduction of CO2.Furthermore,it is found that a Re-based MOF containing 30％ Re-based ligands displays improved activity compared to MOF with 100％ Re-based ligands.This work provides clues to the design and synthesis of bifunctional MOFs toward photocatalytic CO2 reduction.