Electrochemical CO2 reduction on graphdiyne: a DFT Study

Graphdiyne, a new member of the 2D carbon family, has exhibited interesting physiochemical properties attracting academic attention. Its π-conjugated structure with unique sp–sp2 bonding demonstrates a great potential for electrocatalysis. As electrochemical CO2 reduction reaction (CO2RR) has been recognized as a highly promising CO2 utilization technique, the search for active catalysts is critical for the development of CO2RR. Herein, using density functional theory calculations, we studied the activity and selectivity of graphdiyne towards CO2RR. The reaction free energy diagrams are thoroughly investigated, and the results show that the hybridization of sp–sp2 is crucial for high activity owing to the strong adsorption of the *COOH intermediate. Moreover, nitrogen-doping on graphdiyne further improves the activity and selectivity towards CH3OH and CH4 products. The lowest limiting potential of CH3OH on nitrogen-doped graphdiyne is reduced to −0.46 V. The current study predicts the high activity of graphdiyne towards CO2RR, and illustrates the key role of hybridization on the reactivity of the carbon catalysts.