Synthesis of PtNFs/PANI/NG with enhanced electrocatalytic activity towards methanol oxidation

Abstract

A novel Pt nanoflowers/polyaniline/nitrogendoped graphene (PtNFs/PANI/NG) electrocatalyst was prepared by dispersing Pt nanoflowers (PtNFs) onto a polyaniline (PANI) grafted N-doped graphene (NG) matrix through a twostep electrochemical process. Firstly, NG was prepared by a hydrothermal reaction of graphene oxide (GO) with urea, and then electrochemical polymerization of aniline at NG was carried out. Secondly, PtNFs was dispersed onto the film of PANI/NG by electrochemical reduction of H 2 PtCl 6 . The asprepared composites were characterized by SEM, XRD, and Raman spectra. Compared with PtNFs/PANI/G, PtNFs/PANI, and PtNFs/NG catalysts, the novel PtNFs/PANI/NG catalyst exhibits more advantages such as high catalytic activity, excellent poisoning tolerance, and stability characteristic towards methanol electro-oxidation, which is attributed to not only the good dispersion of PtNFs on PANI/NG but also the strong interactions between metal particles and conducting polymer matrixes. The results suggest that the PtNFs/PANI/ NG catalyst can be a promising alternative for catalyst in direct methanol fuel cells (DMFCs).