Heteroatom-induced tensile strain in copper lattice boosts CO₂ electroreduction toward multi-carbon products

Abstract

Strain engineering on metal-based catalysts has been utilized as an efficacious strategy to regulate the mechanism and pathways in various electrocatalytic reactions. However, controlling strain and establishing the strain-activity relationship still remain significant challenges. Herein, three different and continuous tensile strains (CuPd-1.90%, CuAu-3.37%, and CuAg-4.33%) are successfully induced by introducing heteroatoms with different atomic radius. The catalytic performances of CuPd-1.90%, CuAu-3.37%, and CuAg-4.33% display a positive correlation against tensile strains in electrochemical CO₂ reduction reaction (CO₂RR). Specifically, CuAg-4.33% exhibits superior catalytic performance with a 77.9% Faradaic efficiency of multi-carbon products at –300 mA cm^–2 current density, significantly higher than those of pristine Cu (Cu-0%). Theoretical calculations and in situ spectroscopies verify that tensile strain can affect the d-band center of Cu, thereby altering the binding energy of *CO intermediates and Gibbs free energies of the C–C coupling procedure. This work might highlight a new method for precisely regulating the lattice strain of metallic catalysts in different electrocatalytic reactions.

Keywords

CO₂ electroreduction / copper catalysts / heteroatoms doping / multi-carbon products / tensile strain