Efficient CO2 Electroreduction to Multi-Carbon Products by Nanoconfinement Strategy over Cu Catalyst at Industrial Current Density
The electrocatalytic reduction of carbon dioxide (CO2RR) to multi-carbon (C2+) products is of significant interest due to its implications for chemical manufacturing and carbon neutrality. However, the competitive hydrogen evolution reaction (HER) and sluggish C–C coupling kinetics impede selectivity at industrial current densities. Here, we report an interfacial nanoconfinement strategy using N-(2-acetamido)iminodiacetic acid (ADA) to engineer a series of capping layer-covered Cu catalysts (Cu@ADA-x). A volcano-type correlation between capping layer thickness and C2+ selectivity is observed. The optimized Cu@ADA-m catalyst achieves a maximum Faradaic efficiency for C2+ products (FE C2+) of 86.8% and maintains over 80% of its initial FE C2+ after 42 hours at 200 mA cm−2, with an energy efficiency of 38.5%. In-situ Raman spectroscopy and density functional theory (DFT) calculations reveal that the capping architecture stabilizes metastable Cu species and optimizes gas adsorption, enhancing *CO intermediate utilization and lowering C–C coupling energy barriers. This work provides a catalyst design principle for industrial-scale carbon-neutral electrochemical production of multi-carbon products.