Single-Atom Catalysts Supported on the Graphene/Graphdiyne Heterostructure for Effective CO2 Electroreduction

Electrochemical reduction of CO2 to high-energy chemicals is a promising strategy for achieving carbon-neutral energy circulation. However, designing high-performance electrocatalysts for the CO2 reduction reaction (CO2RR) remains a great challenge. In this work, by means of density functional theory calculations, we systematically investigate the transition metal (TM) anchored on the nitrogen-doped graphene/graphdiyne heterostructure (TM-N-4@GRA/GDY) as a single-atom catalyst for CO2 electroreduction applications. The computational results show that Co-N-4@GRA/GDY exhibits remarkable activity with a low limiting potential of -0.567 V for the reduction of CO2 to CH4. When the charged Co-N-4@GRA/GDY system is immersed in a continuum solvent, the reaction barrier decreases to 0.366 eV, which is ascribed to stronger electron transfer between GDY and transition metal atoms in the GRA/GDY heterostructure. In addition, the GRA/GDY heterostructure system significantly weakens the linear scaling relationship between the adsorption free energy of key CO2 reduction intermediates, which leads to a catalytic activity that is higher than that of the single-GRA system and thus greatly accelerates the CO2RR. The electronic structure analysis reveals that the appropriate d-pi interaction will affect the d orbital electron distribution, which is directly relevant to the selectivity and activity of catalysis. We hope these computational results not only provide a potential electrocatalyst candidate but also open up an avenue for improving the catalytic performance for efficient electrochemical CO2RR.

Automated summary

Through density functional theory calculations, this study found that the transition metal single-atom catalyst Co-N-4@GRA/GDY anchored on nitrogen-doped graphene/graphdiyne heterostructure exhibits remarkable activity for CO2 reduction reaction, providing a potential avenue for improving catalytic performance and accelerating CO2RR.