Synthesis and Characterization of PtCo Alloy Nanoparticles Supported on a Reduced Graphene Oxide/g-C₃N₄ Composite for Efficient Methanol Electro-Oxidation.

Abstract

In the development of direct methanol fuel cell (DMFC) the fabrication of an anode comprising of a Pt or Pt-based bi or tri-metallic alloys nanoparticles on a suitable support material having higher stability, higher surface area, electrical conductivity and strong interaction is very important. In the present work we have solved this problem by using a nanocomposite of reduced graphene oxide (rGO) and graphitic carbon nitride (g-C₃N₄) as the support material and deposited PtCo nanoparticles by in-situ chemical reduction. The electro-oxidation of methanol is carried out in an acidic medium. The electrochemical behaviour of as-synthesized PtCo/rGO-gC₃N₄ catalyst was found to be much superior to Pt/rGO-g-C₃N₄ catalysts towards electro-oxidation of methanol and is mainly due to the homogeneous dispersion of PtCo nanoparticles onto rGO-g-C₃N₄ nano composite, higher electrical conductivity and a strong interaction between metal nanoparticles and N group of the support material. By using the as-synthesized electro-catalyst the adsorption or poisoning of Pt due to CO is greatly reduced and more active Pt sites are created for the electro-oxidation of methanol. Thus, the as-synthesized electro-catalyst can be used as an efficient anode material in a direct methanol fuel cell.