Lattice Tuning of Copper Single‐Crystal Surface for Electrochemical Carbon Monoxide Coupling Reaction: A Density Functional Theory Simulation

Abstract

CO is a key intermediate of electrocatalytic CO2 reduction reaction, which determines the product species. Understanding the effect of metal electrode structure on the adsorption ability and reaction activity of CO is helpful for the design of high selective catalysts. Herein, the DFT calculations are used to investigate the relationship between lattice structure and reaction mechanism of CO, with copper electrode of various lattice constants used as catalysts. By analyzing the adsorption and reaction energies of CO at different lattice constants of Cu(111) and Cu(100) surfaces, we found that the CO adsorption ability is proportional to the increase in lattice, and *CO dimerization to *COCO is the main reaction pathway on Cu(100) surface. Furthermore, the forecasted possible reaction mechanism and products suggest that the coupling of *CO and *CHO to *COCHO and then to C2 products is the preferred pathway on Cu(111) surface for the lattice contraction. Alternatively, reduction of *CO to C1 products through *CHO intermediate is more beneficial for the normal and expanded lattice of Cu(111). This work offers an example of the geometrical influence factor on the CO adsorption ability and reaction activity, and helps to understanding the fundamental role of lattice expansion and contraction in catalysis.