The role of adsorbed oleylamine on gold catalysts during synthesis for highly selective electrocatalytic reduction of CO2 to CO

Abstract

The low-coordinated sites of electrocatalysts favour hydrogen evolution, while the edge sites are active for CO₂ reduction. Oleylamine is used to stabilize nanoparticles by adsorbing on the low-coordinated sites. The hydrogen evolution reaction was dramatically suppressed and the FE_CO remained >93% from −0.4 to −0.8 V (vs. RHE) when oleylamine ligands existed on the surface of a gold catalyst. More H⁺ and electrons were involved in the CO evolution reaction, which changed the rate-limiting step from single-electron transfer to the chemical reaction step. The results establish that the surface-adsorbed surfactants during catalyst synthesis have an important effect on CO₂ electrocatalytic reduction.