Ampere-Level Current Density CO₂ Reduction with High C₂₊ Selectivity on La(OH)₃-Modified Cu Catalysts

The carbon dioxide reduction reaction (CO₂RR) driven by electricity can transform CO₂ into high-value multi-carbon (C₂₊) products. Copper (Cu)-based catalysts are efficient but suffer from low C₂₊ selectivity at high current densities. Here La(OH)₃ in Cu catalyst is introduced to modify its electronic structure towards efficient CO₂RR to C₂₊ products at ampere-level current densities. The La(OH)₃/Cu catalyst has a remarkable C₂₊ Faradaic efficiency (FE_C2+) of 71.2% which is 2.2 times that of the pure Cu catalyst at a current density of 1,000 mA cm^-2 and keeps stable for 8 h. In situ spectroscopy and density functional theory calculations both show that La(OH)₃ modifies the electronic structure of Cu. This modification favors *CO adsorption, subsequent hydrogenation, *CO─*COH coupling, and consequently increases C₂₊ selectivity. This work provides a guidance on facilitating C₂₊ product formation, and suppressing hydrogen evolution by La(OH)₃ modification, enabling efficient CO₂RR at ampere-level current densities.