Highly dispersed Pt nanoparticles on nitrogen-doped magnetic carbon nanoparticles and their enhanced activity for methanol oxidation

Pt nanoparticles dispersed nitrogen-doped magnetic carbon nanoparticles (N-MCNPs) were prepared by chemical method, conventional sodium borohydride reduction. Then, those probable applications were evaluated for a support material comparing with Vulcan XC-72 for polymer electrolyte membrane fuel cell. N-MCNPs-supported Pt nanoparticles show a better activity of methanol oxidation reaction compared to Vulcan XC-72-supported one in terms of both mass and electrochemical surface area (ESA) normalized current density. In particular, Pt/N-MCNPs show more enhanced activity based on the mass normalized specific activity rather than ESA normalized activity. For investigation of physical characterizations of Pt/N-MCNPs, and Pt/Vulcan XC-72, X-ray diffraction (XRD), high resolution-transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS) likes various experiments were performed. Especially, to identify the role of nitrogen in the N-MCNPs for Pt nanoparticles dispersion, specific investigation of N 1s XP spectra with peak deconvolution were performed on N-MCNPs support material of the before and after chemical reduction of Pt nanoparticles.