In situ X-ray absorption analysis of ∼1.8 nm dendrimer-encapsulated Pt nanoparticles during electrochemical CO oxidation.

We report an in situ X-ray absorption-fine structure (XAFS) spectroscopic analysis of ∼1.8 nm Pt dendrimer-encapsulated nanoparticles (DENs) during electrocatalytic oxidation of CO. The results indicate that Pt nanoparticles encapsulated within poly(amidoamine) (PAMAM) dendrimers and immobilized on a carbon electrode retain their electrocatalytic activity and are structurally stable for extended periods during CO oxidation. This is a significant finding, because nanoparticles in this size range are good experimental models for comparison to first-principles calculations if they remain stable.

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