Monometallic Catalytic Models Hosted in Stable Metal–Organic Frameworks for Tunable CO₂ Photoreduction

The photocatalytic reduction of CO 2 to energy carriers has emerged as one of the most promising strategies to alleviate the energy crisis and CO 2 pollution, for which the development of catalyst was considered as the determining factor for the accomplishment of this conversion process. In this study, three stable and isostructural metal–organic frameworks (denoted as MOF-Ni, MOF-Co, and MOF-Cu ) have been synthesized and used as heterogeneous catalysts in photocatalytic CO 2 reduction reaction (CO 2 RR). It is worth noting that the MOF-Ni exhibited very high selectivity of 97.7% for photoreducing CO 2 to CO, which has exceeded most of the reported MOF-based catalysts in the field. Significantly, the MOFs associated with a monometallic catalytic center offer a simple and precise structural model which allows us to understand more definitively the specific effects of different metal-ion species on photoreduction of CO 2 as well as the reactive mechanism.