Pt deposited polypyrrole coated graphite oxide and graphene nanosheets as potential fuel cell electrodes

Abstract

Platinum (Pt) deposited polypyrrole (PPy) coated graphite oxide (GO) sheets and graphene nanosheets (GNS) in the present study were an original attempt for the fabrication of fuel cell electrodes. The shortest and most effective impregnation technique of Pt catalysts on the surface of GO sheets and GNS based nanocomposites was achieved by sonication process about 2 hr. The characterization results of different deposition techniques showed that the presence of oxygen surface groups and the amount of PPy in nanocomposites favored the Pt dispersion and hindered the aggregation of Pt particles on the support surface. As the amount of PPy increased, catalyst dispersion on the surface of nanocomposite could be maximized due to the electronic properties of PPy but catalyst-particle size range increased. On the other hand, as the amount of oxygen functional groups on the surface of GO sheets increased, smaller size catalyst particles dispersed on the surface. Therefore, smaller catalyst size enhanced the specific surface area and thus a more efficient catalyst was provided by tailoring the amount of surface oxygen groups and PPy in nanocomposite structure.