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 (CO₂ RR) relies on the simultaneous improvement of mass activity (usually lower than 10 mA mg^-1 _Au 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^-1 _Au with 97 % CO faradaic efficiency (FE_CO ) 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 CO₂ RR and beyond.