Boosting electrochemical conversion of CO2 to ethanol through the confinement of pyridinic N-B layer on copper nanoparticles

Abstract

Developing efficient electrocatalysts for CO2 reduction has gained significant attention in the field of sustainable energy, especially the Cu-based catalysts for CO2 conversion to valuable alcohols. In this study, we developed Cu nanoparticles supported on pyridinic N-B doped graphene nanoribbons/amorphous carbon (Cu/BNC-1) as an electrocatalyst for CO2 reduction, exhibiting substantially improved ethanol (EtOH) conversion rate in terms of activity, selectivity, and stability. The Cu/BNC-1 achieved a remarkable 58.64 % Faradaic efficiency (FE) for producing EtOH at −1.0 V vs. RHE with a current density of 20.4 mA cm−2 in 0.5 M KHCO3 electrolyte. In-situ Raman, FT-IR, and density functional theory (DFT) calculations demonstrated that the high C2+ product selectivity of Cu/BNC-1 attributed to the pyridinic N-B modulation, lowering the CO dimerization barrier. Moreover, the synergistic confinement effect of Cu and BNC can stabilize the C-O bond of the *HOCCH intermediate, thereby increasing the yield of EtOH.