Cold plasma-activated Cu-Co catalysts with CN vacancies for enhancing CO2 electroreduction to low-carbon alcohol

Abstract

Electrocatalytic CO₂ reduction reaction to low-carbon alcohol is a challenging task, especially high selectivity for ethanol, which is mainly limited by the regulation of reaction intermediates and subsequent C–C coupling. A Cu-Co bimetallic catalyst with CN vacancies is successfully developed by H₂ cold plasma toward a high-efficiency CO₂RR into low-carbon alcohol. The Cu-Co PBA-V_CN (Prussian blue analogues with CN vacancies) electrocatalyst yields methanol and ethanol as major products with a total low-carbon alcohol FE of 83.8% (methanol: 39.2%, ethanol: 44.6%) at −0.9 V vs. RHE, excellent durability (100 h) and a small onset potential of −0.21 V. ATR-SEIRAS (attenuated total internal reflection surface enhanced infrared absorption spectroscopy) and DFT (density functional theory) reveal that the steric hindrance of V_CN can enhance the CO generation from *COOH, and the C–C coupling can also be increased by CO spillover on uniformly dispersed Cu atoms. This work provides a strategy for the design and preparation of electrocatalysts for CO₂RR into low-carbon alcohol products and highlights the impact of catalyst steric hindrance to catalytic performance.