Highly Dispersed Platinum Nanoparticles Anchored on Polypyrrole Nanospheres as Anode Catalyst for Methanol Oxidation Reaction

A novel catalyst of platinum nanoparticles (PtNPs) decorated on poly-diallyldimethylammonium chloride (PDDA) functionalized polypyrrole nano-spheres (PNS) has been prepared by simple wet-chemical method. PNS with large surface area and high dispersion was prepared by chemical polymerization of pyrrole. PtNPs with uniformed size and high dispersion have been successfully decorated on PDDA functionalized PNS via a sodium borohydride reduction process. The PNS/PtNPs is characterized by transmission electron microscopy, high resolution transmission electron microscopy, energy-dispersive X-ray, X-ray diffraction, X-ray photoelectron spectroscopy and inductively coupled plasma spectrum instrument. The results show that the PtNPs with sizes of approximate 5-6 nm are uniformly dispersed on the surface of PNS. Compared to Vulcan XC-72 carbon black supported same mass PtNPs (XC-72/PtNPs), PNS/PtNPs show larger mass activity (374 mA mg(-1)) and stronger poisoning-tolerance (I-f/I-b = 2.85) due to high dispersion of PtNPs on large surface of PNS. The performance indicates that PNS/PtNPs may be an excellent anode catalyst for methanol oxidation reaction.