Electrodeposition of platinum nanoparticles on polypyrrole-functionalized graphene

In this study, the new electrocatalyst of platinum support on polypyrrole-functionalized graphene (GNS–PPy/PtNPs) is reported. The polypyrrole-functionalized graphene (GNS–PPy) is constructed first with graphene nanosheets (GNS) and polypyrrole (PPy) particles by constant potential deposition. And then PtNPs are deposited on the surface of GNS–PPy by cyclic voltammetry. The as-prepared GNS–PPy/PtNPs is characterized by scanning electron microscopy, energy-dispersive spectroscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The prepared GNS–PPy/PtNPs catalyst is employed for methanol oxidation reactions. Compared with GNS/PtNPs and PPy/PtNPs, the GNS–PPy/PtNPs has higher catalytic activity (508 mA/mg), better stability, and stronger poisoning-tolerance (I _f/I _b = 4.18) due to high dispersion of PtNPs on large surface of GNS–PPy as well as synergic effect among the GNS, PPy particles, and PtNPs. The experimental results indicate that GNS–PPy/PtNPs may be an ideal candidate catalyst for direct methanol fuel cell.