Boosting Formate Production in Electrocatalytic CO2 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 CO₂ 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^-2, along with stable performance for over 15 h at -1.0 V versus the reversible hydrogen electrode. Both in situ 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 CO₂ to formate. In addition, the exposed bimetallic interface promotes efficient capture and activation of CO₂ 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.