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.