Regulating Efficient and Selective Single‐atom Catalysts for Electrocatalytic CO2 Reduction

Anchoring transition metal (TM) atoms on suitable substrates to form single‐atom catalysts (SACs) is a novel approach to constructing electrocatalysts. Graphdiyne with sp−sp2 hybridized carbon atoms and uniformly distributed pores have been considered as a potential carbon material for supporting metal atoms in a variety of catalytic processes. Herein, density functional theory (DFT) calculations were performed to study the single TM atom anchoring on graphdiyne (TM1−GDY, TM=Sc, Ti, V, Cr, Mn, Co and Cu) as the catalysts for CO2 reduction. After anchoring metal atoms on GDY, the catalytic activity of TM1−GDY (TM=Mn, Co and Cu) for CO2 reduction reaction (CO2RR) are significantly improved comparing with the pristine GDY. Among the studied TM1−GDY, Cu1−GDY shows excellent electrocatalytic activity for CO2 reduction for which the product is HCOOH and the limiting potential (UL) is −0.16 V. Mn1−GDY and Co1−GDY exhibit superior catalytic selectivity for CO2 reduction to CH4 with UL of −0.62 and −0.34 V, respectively. The hydrogen evolution reaction (HER) by TM1−GDY (TM=Mn, Co and Cu) occurs on carbon atoms, while the active sites of CO2RR are the transition metal atoms . The present work is expected to provide a solid theoretical basis for CO2 conversion into valuable hydrocarbons.