Manipulating Au-CeO2 Interfacial Structure Toward Ultrahigh Mass Activity and Selectivity for CO2 Reduction

Deploying the application of Au-based catalysts directly on CO2 reduction reactions (CO2RR) relies on the simultaneous improvement of mass activity (usually lower than 10 mA mg(Au)(-1) at -0.6 V) and selectivity. To achieve this target, we herein manipulate the interface of small-size Au (3.5 nm) and CeO2 nanoparticles through adjusting the surface charge of Au and CeO2. The well-regulated interfacial structure not only guarantees the utmost utilization of Au, but also enhances the CO2 adsorption. Consequently, the mass activity (CO) of the optimal AuCeO2/C catalyst reaches 139 mA mg(Au)(-1) with 97 % CO faradaic efficiency (FECO) at -0.6 V. Moreover, the strong interaction between Au and CeO2 endows the catalyst with excellent long-term stability. This work affords a charge-guided approach to construct the interfacial structure for CO2RR and beyond.