Selective electrochemical CO2 conversion to multicarbon alcohols on highly efficient N-doped porous carbon-supported Cu catalysts

Abstract

The selective and efficient electrocatalytic transformation of carbon dioxide (CO₂) to multicarbon alcohols (e.g., C₂H₅OH and C₃H₇OH) is a challenge in renewable and sustainable energy research. Herein, a series of hybrid catalysts consisting of Cu nanoparticles supported on N-doped porous carbon (Cu/NPC) were prepared. It was demonstrated that the selectivity for C₂H₅OH or C₃H₇OH could be tuned by introducing N-doped porous carbon materials as cocatalysts with different pyridinic N contents, which could in situ produce a reactive CO intermediate from CO₂. By varying the pyridinic N content, highly selective production of multicarbon alcohols was achieved using the Cu/NPC hybrid catalysts with a high faradaic efficiency for one pot production of multicarbon alcohols up to 73.3% at −1.05 V (vs. RHE). The faradaic efficiency for C₂H₅OH and C₃H₇OH was 64.6% and 8.7%, respectively. The pyridinic N species were likely the CO-producing sites and together with Cu catalytic sites acted cooperatively to produce C₂H₅OH and C₃H₇OH via a two-site mechanism for efficient CO₂ reduction to multicarbon alcohols. These findings provide novel guidance for the rational design of electrocatalysts and for tuning the catalytic activity and selectivity for multicarbon alcohol production from CO₂.