Boosting Formate Production in Electrocatalytic CO Reduction on Bimetallic Catalysts Enriched with In-Zn Interfaces.

We present an effective strategy for developing the dispersing strong-binding metal In on the surface of weak-binding metal Zn, which modulates the binding energy of the reaction intermediates and further facilitates the efficient conversion of CO to formate. The In-Zn interface (In-Zn2) benefits from the formation of active sites through favorable orbital interactions, leading to a Faradaic efficiency of 82.7% and a formate partial current density of 12.39 mA cm, along with stable performance for over 15 h at -1.0 V versus the reversible hydrogen electrode. Both Fourier transform infrared spectroscopy and density functional theory calculations show that the In-Zn bimetallic catalyst can deliver superior binding energy to the *OCHO intermediate, thereby fundamentally accelerating the conversion of CO to formate. In addition, the exposed bimetallic interface promotes efficient capture and activation of CO molecules and the dynamics within the In-Zn catalyst significantly reduce the energy barrier associated with the generation of HCOO, thus augmenting the selectivity and catalytic activity for formate generation.