Efficient CO2 Electroreduction to CO on Chiral Nanostructured Au Films

The electroreduction of CO₂ to CO presents a promising strategy for converting CO₂ to value-added chemicals. However, achieving high Faradaic efficiency (FE) at elevated current densities is a persistent challenge, suffering from difficult activation of CO₂ and the high energy barrier for reaction intermediates. Herein, we propose that the spin-polarized chiral nanostructured Au films (CNAFs) can facilitate the activation of CO₂ over the surface with parallel electron spin alignment and utilize helical lattice distortions to reduce the energy barrier for the *COOH intermediate, leading to enhanced CO production. The CNAFs, characterized as helically twisted nanoflakes, were fabricated via electrodeposition using histidine as a symmetry-breaking agent. The CNAFs exhibited a maximum FE_CO of ∼99% at −0.19 V vs the reversible hydrogen electrode (RHE), and an FE_CO of ∼88% at a current density of ∼180 mA/cm² at −0.59 V vs RHE. Our findings elucidate the underlying mechanisms of CO₂ conversion, paving the way for the innovation of spin-polarized catalysts with specific defects.