Anomalous C‐C coupling on under‐coordinated Cu(111) – a case study of Cu nanopyramids for CO2 reduction reaction by molecular modelling

Abstract

Converting CO2 to high value‐added C2 hydrocarbons by CO2 reduction reaction attracted attention due to higher energy density, readiness for transportation, and established utilization infrastructure. Herein, it was demonstrated that tailoring the copper catalyst morphology by forming nanopyramids offers alternative routes to promote C2 production. Using density functional theory calculations, five polycrystalline Cu nanopyramids with various orientations, shapes, and exposing facets were investigated. Three investigated nanopyramids favored the C2 production to different extents due to anomalous C−C coupling behaviors. The underlying reason for such C−C coupling was the pyramidal effect on under‐coordinated Cu (111) surface from the nanopyramids. The pyramidal effect includes improved *CO adsorption, geometrically preferable sites for C−C coupling, and enhanced electron transfer. Based on these results, a C2 active site screening principle was developed: an extended “square” principle, which can serve as a new morphology design rule for efficient catalyst development.