Tuning CO2 electroreduction by facet-dependent metal-support interaction

Electrochemical carbon dioxide reduction reaction (CO2RR) helps to build a sustainable carbon cycle system. The selectivity and stability of CO2RR catalysts can be tuned by manipulating Metal-Support Interaction (MSI). Here, we conducted a theoretical and experimental research on the interaction between Ag nanoparticles and diverse crystal faces of Cu2O. It was found the strong electron transfer from Ag to (100) facet of hexahedral Cu2O enabled the formation of charge-redistributed interface with positively charged Ag and negatively charged Cu2O, which was more favorable to the stability of integrated structure and CO2-to-CO catalytic process compared to Ag-decorated octahedral and dodecahedral Cu2O with exposed (111) and (110) facets, respectively. Consequently, the composite of Ag on hexahedral Cu2O exhibited an impressive CO Faradaic efficiency of 93%, surpassing Ag on octahedral and dodecahedral Cu2O as well as individual Ag and Cu2O nanoparticles. This work provides an effective avenue to tune CO2RR process by interface engineering.