Positive Valent Metal Sites in Electrochemical CO 2 Reduction Reaction.

The discovery of high-performance catalysts for the electrochemical CO 2 reduction reaction (CO 2 RR) has faced an enormous challenge for years. The lack of cognition about the surface active structures or centers of catalysts in complex conditions limits the development of advanced catalysts for CO 2 RR. Recently, the positive valent metal sites (PVMS) are demonstrated as a kind of potential active sites, which can facilitate carbon dioxide (CO 2 ) activation and conversation but are always unstable under reduction potentials. Many advanced technologies in theory and experiment have been utilized to understand and develop excellent catalysts with PVMS for CO 2 RR. Here, we present an introduction of some typical catalysts with PVMS in CO 2 RR and give some understanding of the activity and stability for these related catalysts.