Ampere-Level Current Density CO Reduction with High C Selectivity on La(OH)-Modified Cu Catalysts.

The carbon dioxide reduction reaction (CORR) driven by electricity can transform CO into high-value multi-carbon (C) products. Copper (Cu)-based catalysts are efficient but suffer from low C selectivity at high current densities. Here La(OH) in Cu catalyst is introduced to modify its electronic structure towards efficient CORR to C products at ampere-level current densities. The La(OH)/Cu catalyst has a remarkable C Faradaic efficiency (FE) of 71.2% which is 2.2 times that of the pure Cu catalyst at a current density of 1,000 mA cm and keeps stable for 8 h. In situ spectroscopy and density functional theory calculations both show that La(OH) modifies the electronic structure of Cu. This modification favors *CO adsorption, subsequent hydrogenation, *CO─*COH coupling, and consequently increases C selectivity. This work provides a guidance on facilitating C product formation, and suppressing hydrogen evolution by La(OH) modification, enabling efficient CORR at ampere-level current densities.