Synthesis and Electrochemical Characterization of Platinum and Ruthenium Nanoparticles Encapsulated in PAMAM-G4OH Dendrimers for Oxygen Reduction in the Presence of Methanol

摘要

In this work, we describe the preparation of composites of Pt, Ru and bimetallic Pt-Ru nanoparticles encapsulated in generation-four hydroxyl-terminated dendrimers (PAMAM-G4OH). The absorption of the metal ions and their chemical reduction were followed by UV-vis spectroscopy. Subsequently, the dendrimers encapsulating the Pt, Ru or Pt-Ru particles were immobilized on the oxidized surface of a glassy carbon electrode (GCE). Cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements were used to determine the oxygen reduction reaction (ORR) kinetics on this surface in aqueous sulfuric acid media and in sulfuric acid solution containing methanol. Preliminary results show that the nanoelectrocatalyst exhibits good stability in these media and good electrocatalytic activity for the ORR in the presence of methanol.