Pt-Rh alloy nanodendrites for improved electrocatalytic activity and stability in methanol electrooxidation reaction

Structure-controlled metallic catalysts have been well known to exhibit an improved electrocatalytic activity due to modulated surface structures favorable for electrochemical reactions. We have synthesized Pt-Rh nanodendritic catalyst for methanol electrooxidation by a polyol method in the presence of PVP and L-ascorbic acid in aqueous solution. The as-synthesized Pt-Rh alloy nanoparticles exhibited a dendritic structure with well-defined alloy formation between the Pt and Rh metallic phase, uniform particle size and shape, and high-index facets. Furthermore, we found remarkably improved electrochemical properties of the Pt-Rh alloy nanodendrites i.e. improved electrocatalytic activity and stability for methanol electrooxidation in comparison with spherical Pt-Rh and pure Pt nanoparticles. (C) 2014 Elsevier B.V. All rights reserved.