Electrocatalytic O2 reduction at glassy carbon electrodes modified with dendrimer-encapsulated Pt nanoparticles.

Platinum dendrimer-encapsulated nanoparticles (DENs) were prepared within fourth-generation, hydroxyl-terminated, poly(amidoamine) dendrimers and immobilized on glassy carbon electrodes using an electrochemical coupling strategy. X-ray photoelectron spectroscopy, electron microscopy, and electrochemical experiments confirmed that the Pt DENs were about 1.4 nm in diameter and that they remained within the dendrimer following surface immobilization. The resulting Pt DEN films were electrocatalytically active for the oxygen reduction reaction. The films were also robust, surviving up to 50 consecutive cyclic voltammograms and sonication.