Ball-like Pt nanoparticles on GO-modified carbon fiber cloth with high electrocatalytic activity for methanol oxidation

Abstract

A direct methanol fuel cell (DMFC) electrode based on the carbon fiber cloth (CFC) modified with wrap-like graphene oxide (GO) decorated with platinum nanoparticles was prepared by multicycle CV method. Also, the Pt/CFC composite and GO/CFC composite were prepared by multicycle CV and potentiostatic method, respectively. The four electrodes (GO-Pt/CFC, Pt/CFC, GO/CFC and CFC) were tested in a fuel cell for electro-oxidation of methanol and were analyzed by scanning electron microscopy (SEM) and X-Ray powder diffraction (XRD). The SEM image indicated that the surface of CFC was covered by a wrap-like graphene oxide (GO) film completely, which increased the contact area with methanol solution and provided more load points. And the Pt nanoparticles supported GO/CFC electrode possessed the ball-like morphology. The electrochemical measurements showed that the electrocatalytic peak current density of methanol oxidation of GO-Pt/CFC electrode (218 mA/cm2) was about 27% higher than Pt/CFC electrode (172 mA/cm2) and the steady-state current density of GO-Pt/CFC electrode was 57.6%, 114.5% and 497.9% higher than that of Pt/CFC, GO/CFC and CFC electrodes, respectively. And this date revealed that the ball-like morphology of Pt nanoparticles and a wrap-like GO film coated on CFC surface were favorable to improve the electrocatalytic oxidation activity of methanol.