Controllable Cu0-Cu+ Sites for Electrocatalytic Reduction of Carbon Dioxide

Cu-based electrocatalysts facilitate CO2 electrochemical reduction (CO2ER) to produce multi-carbon products. However, the roles of Cu-0 and Cu+ and the mechanistic understanding remain elusive. This paper describes the controllable construction of Cu-0-Cu+ sites derived from the well-dispersed cupric oxide particles supported on copper phyllosilicate lamella to enhance CO2ER performance. 20 % Cu/CuSiO3 shows the superior CO2ER performance with 51.8 % C2H4 Faraday efficiency at -1.1 V vs reversible hydrogen electrode during the 6 hour test. In situ attenuated total reflection infrared spectra and density functional theory (DFT) calculations were employed to elucidate the reaction mechanism. The enhancement in CO2ER activity is mainly attributed to the synergism of Cu-0-Cu+ pairs: Cu-0 activates CO2 and facilitates the following electron transfers; Cu+ strengthens *CO adsorption to further boost C-C coupling. We provide a strategy to rationally design Cu-based catalysts with viable valence states to boost CO2ER.

Automated summary

This study aims to enhance the CO2ER performance by increasing the synergism of Cu-0-Cu+ pairs, where Cu-0 activates CO2 molecules and facilitates electron transfer, while Cu+ strengthens *CO adsorption to further promote C-C coupling.