CO2 electrolysis to multi-carbon products in strong acid at ampere-current levels on La-Cu spheres with channels.

Achieving satisfactory multi-carbon (C₂₊) products selectivity and current density under acidic condition is a key issue for practical application of electrochemical CO₂ reduction reaction (CO₂RR), but is challenging. Herein, we demonstrate that combining microenvironment modulation by porous channel structure and intrinsic catalytic activity enhancement via doping effect could promote efficient CO₂RR toward C₂₊ products in acidic electrolyte (pH ≤ 1). The La-doped Cu hollow sphere with channels exhibits a C₂₊ products Faradaic efficiency (FE) of 86.2% with a partial current density of −775.8 mA cm⁻². CO₂ single-pass conversion efficiency for C₂₊ products can reach 52.8% at −900 mA cm⁻². Moreover, the catalyst still maintains a high C₂₊ FE of 81.3% at −1 A cm⁻². The channel structure plays a crucial role in accumulating K⁺ and OH^- species near the catalyst surface and within the channels, which effectively suppresses the undesired hydrogen evolution and promotes C–C coupling. Additionally, the La doping enhances the generation of *CO intermediate, and also facilitates C₂₊ products formation. Efficient electroreduction of CO2 to multi-carbon products under strong acidic condition is highly challenging. Here, the authors demonstrate that combining microenvironment modulation and La doping effect could promote multicarbon products generation in acidic electrolyte. [ABSTRACT FROM AUTHOR]