Alkaline O₂ reduction on oxide-derived Au: high activity and 4e¯ selectivity without (100) facets.

Gold films produced from gold oxide precursors ("oxide-derived Au") were compared to polyhedral Au nanoparticles for electrocatalytic alkaline O2 reduction. Despite having no detectable abundance of (100) facets, oxide-derived Au exhibited 4e(-) selectivity and surface-area-normalized activity that rivaled cubic Au nanoparticles with high (100) abundance. The activity of oxide-derived Au likely arises from active sites at the surface terminations of defects that are trapped during gold oxide reduction.