Potentials and reaction mechanisms of metal-free B/g-C3N4/graphene catalyst for reducing carbon monoxide to ethylene

The electrocatalytic reduction of carbon monoxide (CO) to high-value multicarbon chemicals represents an effective strategy for achieving a sustainable carbon cycle. In recent years, researchers have developed a variety of highly efficient catalysts for the reduction of CO. Among these materials, non-metallic catalysts demonstrate considerable energy application due to their environmentally friendly, low-cost and compositionally tunable properties. In this study, we innovatively designed a non-metallic catalyst (B/g-C₃N₄/GN) by introducing boron (B) atoms to the heterostructure of graphitic carbon nitride (g-C₃N₄) and graphene (GN) to reduce CO through first-principle calculations. The catalyst effectively promotes the conversion of CO to ethylene (CH₂CH₂) with a free energy increase of 0.22 eV for the potential-determining step (PDS), and the energy barrier for C–C coupling is only 0.37 eV, which demonstrates the efficient and stable catalytic performance. The design of the B/g-C₃N₄/GN material provides a new approach in the field of electrocatalysis.