Graphical abstract

Electrochemical CO₂ reduction reaction (CO₂RR) is a promising method to convert CO₂ into high value carbon products. For commercial applications, the energy efficiency of CO₂RR needs enhancement. Designing superior electrocatalysts is important to increase energy efficiency. This paper reports that the catalytic properties of Au can be enhanced by metal-support interaction (MSI) through CeO₂ and a multi-walled carbon nanotube (MWCNT). A heterostructure for MSI is constructed by matching work function using CeO₂ and MWCNT to modify the electronic structure of Au via cascade electron transfer. Through MSI, the Au/CeO₂/MWCNT heterostructure exhibits 4.2 times higher CO selectivity than Au/CB, and 1.6 times higher CO selectivity than Au/CeO₂ at 200 mA cm⁻². As a result, the energy efficiency of CO production from CO₂RR can be significantly increased using Au/CeO₂/MWCNT. These findings show the importance of MSI in designing high-performance catalysts for CO₂RR.