Effects of Uniaxial Lattice Strain and Explicit Water Solvation on CO<sub>2</sub> Electroreduction over a Cu Electrode: A Density Functional Theory Perspective
Yuanyuan Du, Wei An
Abstract
Strain engineering of metal-based catalysts has emerged as an efficient solution to breaking of scaling relations of adsorbed species in a catalytic reaction. However, many aspects of the fundamental origin are still yet to be addressed at the atomic scale. Herein, we have simulated applying uniaxial lattice strain to two Cu facets with explicit water solvation for their CO2 electroreduction (CO2RR) performance. It is revealed that C1 key reaction intermediates of CO2RR follow a reverse linear scaling relation that *COOH and *CHO are enhanced in binding strength with weaker *CO adsorption on Cu(211) and Cu(100) facets as a consequence of uniaxial lattice strain. The coupling between intrinsic lattice strain and adsorbate-induced strain to the surface site is responsible for such a relation critically determined by strain nature (i.e., compressive or tensile) and adsorption mode. The CO2RR toward CH4 production is predicted to yield the lowest limiting potential from *CO + (H+ + e–) → *CHO on Cu(211) under 12.1% of tensile strain, but from CO2 + (H+ + e–) → *COOH on Cu(100) under 6.3% of tensile strain. The water solvation effect on CO2RR is also discussed.