Transition metal doped C3N monolayer as efficient electrocatalyst for carbon dioxide electroreduction: A computational study

Recently, two-dimensional graphitic carbon nitrides have emerged as potential electrocatalysts for CO2 electroreduction (CO2ER). Herein, a series of transition metal (M = Mn-Cu, Ru-Ag) doped C3N monolayer (M-C3N) as a novel CO2ER catalyst has been investigated by employing the density functional method. By a careful computational screening, Mn-C3N is identified as the best catalyst for CO2ER, due to its high catalytic activity and high selectivity. HCOOH is the final product with a low overpotential of 0.04 V and a low kinetic energy barrier of 0.75 eV. The hydrogen evolution is also suppressed on Mn-C3N surface. Therefore, the CO2ER activity could be tuned by adjusting the metal atom in the C3N monolayer, which may shed new light on designing novel C3N-based CO2ER catalyst.