Fig. 3: Palladium–silver intermixing during reduction by hydrogen.

a Palladium–silver intermixing occurs after reduction of PdOx on Ag(111) as evidenced by the increased Ag1−xPdx alloy peak in the Ag3d5/2 region (green) using AP-XPS. Spectra are for (i) as-deposited 0.10 ML palladium on Ag(111), (ii) after reduction of PdOx on Ag(111), and (iii) the difference trace (ii−i) to better illustrate the increase in the PdAg alloy signal. b The formation of PdOx on Ag(111) decreases the palladium–silver interface area because of palladium dewetting while the reduction of PdOx on Ag(111) induces palladium–silver intermixing as illustrated by the increase in the Ag1−xPdx alloy peak.