Immobilized triatomic CuB2 clusters on 2D carbon nitride: highly selective conversion of CO to ethanol at low potentials

Abstract

A promising pathway for carbon usage and energy storage is electrocatalytic reduction of CO to form high-value multi-carbon products. Herein, the d–p coupled triatomic catalyst CuB₂@g-C₃N₄ with significant activity and selectivity for ethanol is presented for the first time. Density functional theory calculations elucidate that these spatially confined triatomic centers are capable of immobilizing multiple CO molecules, providing an exclusive reaction channel for direct C–C coupling. The CuB₂@g-C₃N₄ catalyst can effectively reduce the energy barrier of CO dimerization to 0.46 eV. The limiting potential is only −0.19 V, which is much smaller than that of other Cu-based catalysts. Additionally, the CuB₂@g-C₃N₄ catalyst can effectively inhibit the generation of competing C1 products and hydrogen evolution reactions. Excitingly, CuB₂ loading makes g-C₃N₄ more optically active in visible and even infrared light. This work provides important ideas for the atomically precise design of novel d–p coupled catalysts for the direct conversion of CO₂/CO into energetic fuels and high-value chemicals.