Pt–Ru/multi-walled carbon nanotubes as electrocatalysts for direct methanol fuel cell

Abstract

Multi-walled carbon nanotubes (MWNTs) have been synthesized by hemical vapour deposition technique using AB 3 alloy hydride catalyst and platinum supported MWNT (Pt/MWNT) and platinum–ruthenium supported MWNT (Pt–Ru/MWNT) electrocatalysts have been prepared by chemical reduction method. MWNT and electrocatalysts have been characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and energy dispersive X-ray analysis (EDX). The anode and cathode electrodes of direct methanol fuel cells (DMFC) have been fabricated using Pt–Ru/MWNT and 1:1 Pt / MWNT + Pt / C electrocatalyst, respectively. Performances of DMFC with these electrodes have been studied at different temperatures and the results have been discussed. A maximum power density of 39.3 mW / cm 2 at a current density of 130 mA / cm 2 has been obtained, which could be attributed to dispersion and accessibility of MWNT support and Pt–Ru in the electrocatalyst mixture for methanol oxidation reaction.