The　electrocatalytic　CO2　or　CO　reduction　reaction　is　a　complex　proton-coupled　electron　transfer　reaction,　in　which　protons　in　the　electrolyte　have　a　critical　effect　on　the　surface　adsorbed　*H　species　and　the　multi-carbon　oxygenate　products　such　as　ethanol.　However,　the　coupling　of　*H　and　carbon-containing　intermediates　into　C2+　oxygenates　can　be　severely　hampered　by　the　inappropriate　distributions　of　those　species　in　the　catalytic　interfaces.　In　this　work,　the　controlled　distribution　of　highly　dispersed　CeOx　nanoclusters　is　demonstrated　on　Cu　nanosheets　as　an　efficient　CO　electroreduction　catalyst,　with　Faradaic　efficiencies　of　ethanol　and　total　oxygenates　of　35%　and　58%,　respectively.　The　CeOx　nanoclusters　(2−5　nm)　enabled　efficient　water　dissociation　and　appropriate　distribution　of　adsorbed　*H　species　on　the　Cu　surface　with　carbon-containing　species,　thus　facilitating　the　generation　of　C2+　oxygenate　products.　In　contrast,　pristine　Cu　without　CeOx　tended　to　form　ethylene,　while　the　aggregated　CeOx　nanoparticles　promoted　the　surface　density　of　*H　and　subsequent　H2　evolution.　©　2024　Wiley-VCH　GmbH.