Regulating Ag–Cu synergy effect via Cu doping numbers to boost CO2 electroreduction on Ag14 nanoclusters

An Ag14−xCux series (Ag14, (AgCu)14-1, (AgCu)14-2), was synthesized. Moderate Cu doping in (AgCu)14-1 leads to stronger Ag–Cu synergy and higher Cu valence states, which promote *CO adsorption and thereby improve CO 2 -to-CH 4 selectivity.