Theoretical insights into CO2 reduction reaction on a CuPc/graphene single-atomic catalyst

Abstract

Excessive CO₂ emission has caused severe greenhouse problems. CO₂ reduction reaction (CO₂RR) is considered to be a promising strategy to effectively reduce CO₂ emission, which not only captures CO₂ in large quantity, but also produces high value-added chemicals. Herein, CO₂RR on the CuPc/graphene single-atomic catalyst has been studied via density functional theory (DFT) calculations. It shows that CO₂ is inclined to convert to CH₃OH, followed by HCOOH and CH₄. The most favored pathway to produce CH₃OH is *CO₂ → *COOH → *CO → *CHO → *OCH₂ → *OCH₃ → *OHCH₃, for which the potential-limiting step is *CO₂ → *COOH (endothermic by 1.41 eV). Both density of states and differential charge further indicate the high reactivity of single atomic Cu, and uncover the effect of electrostatic interaction on the hydrogenation pathway. This study can provide an insight into the structure–reaction relationship for CO₂RR on CuPc/graphene, and help guide the design of highly effective catalysts.