High dispersion and electrocatalytic properties of platinum nanoparticles on graphitic carbon nanofibers (GCNFs)

摘要

Highly dispersed platinum nanoparticles were electrodeposited on graphitic carbon nanofibers (GCNFs) by cyclic voltammetry (CV) in 7.7mM H_2PtCl_6+0.5 M HCl aqueous solutions.The graphitic carbon nanofibers (GCNFs) used in this paper were grown directly on a graphite disk by chemical vapor deposition (CVD).The micrographs and element composition of Pt/GCNFs/graphite electrode were characterized by scanning electron microscopy (SEM) and electron diffraction spectroscopy (EDS).The electrocatalytic properties of Pt/GCNFs/graphite electrode for methanol oxidation have been investigated by CV and excellent electrocatalytic activity can be observed even at very low platinum loading (m_d=8.79mug cm~(-2)).The highest mase activity (MA) for methanol oxidation reaches 323 Ag~(-1) when Pt/GCNFs/graphite electrode was cycled at a sweep rate of 50 mVs~(-1) by CV in 2M CH_3OH+1MH_2SO_4 aqueous solutions.This may be attribued to the small particle size and high dispersion of platinum particles coated on GCNFs and shows good potential application in direct methanol fuel cell (DMFC).Additionally,the long-term cycling stability of platinum catalysts was also investigated.