Diffusion of adsorbed CO on platinum (100) and (111) oriented nanosurfaces

Platinum nanocubes exhibiting oriented surface domains were used to study the electrooxidation of chemisorbed CO (COchem.). The amount of oriented surface nanodomains was characterized by hydrogen underpotential deposition (Hupd), bismuth and germanium spontaneous adsorption/oxidation. The surface diffusion of COchem toward low coordination sites, where oxidation is expected to take place, is more rapid on (111) than on (100) nanodomains and no diffusion of CO from (100) domains toward (111) nanodomains seems to occur.

► COchem oxidation on Pt particles exhibiting (100) and (111) oriented surface nanodomains ► Difference in COchem diffusion rates on (111) and (100) nanosurface ► No diffusion of COchem from (100) to (111) nanosurfaces ► Edges act as active oxidation sites and diffusion barriers.