Preparation and electrocatalytic oxidation performance of Pt/MnO2–graphene oxide nanocomposites

A simple and eco-friendly approach was developed to prepare manganese dioxide functionalized reduced graphene oxide supported Pt nanocomposites (Pt/MnO2–RGO) via chemical reduction process. The morphology and structure of as-prepared catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR) and X-ray diffraction (XRD). Subsequently, electrochemical properties of catalysts were systematically investigated by cyclic voltammetry (CV). As a result, the ultrafine Pt nanoparticles with an average diameter of 2.9 nm were uniformly dispersed on the MnO2–RGO surface. The Pt/MnO2–RGO catalysts exhibited the superior electrochemical active surface area (79.4 m2 g−1) and specific peak current density for methanol oxidation (24.7 mA cm−2), compared to Pt/reduced graphene oxide (Pt/RGO) and Pt/carbon black (Pt/CB). The improved electrocatalytic activity was mainly attributed to the better dispersion of Pt nanoparticles as well as the synergistic effect of the modified supports.

The synthesis route of Pt/MnO2–RGO is illustrated. First, the graphite oxide was prepared from natural flake graphite by a modified Hummers’ method. Subsequently, the MnO2 were anchored directly on the surface of GO using KMnO4 as MnO2 precursor and carbon atom of RGO as a reductant at heating condition. The catalytic property of the composite electrode had been analyzed.Figure optionsDownload as PowerPoint slide