Synthesis And Characterization Of Platinum Nanoparticles On In Situ Grown Carbon Nanotubes Based Carbon Paper For Proton Exchange Membrane Fuel Cell Cathode

摘要

Multi-walled carbon nanotubes (MWCNTs) based micro-porous layer on the carbon paper substrates was prepared by in situ growth in a chemical vapor deposition setup. Platinum nanoparticles were deposited on in situ grown MWCNTs/carbon paper by a wet chemistry route at <100℃. The in situ MWC-NTs/carbon paper was initially surface modified by silane derivative to incorporate sulfonic acid-silicate intermediate groups which act as anchors for metal ions. Platinum nanoparticles deposition on the in situ MWCNTs/carbon paper was carried out by reducing platinum (II) acetylacetonate precursor using glacial acetic acid. High resolution TEM images showed that the platinum particles are homogeneously distributed on the outer surface of MWCNTs with a size range of 1-2nm. The Pt/MWCNTs/carbon paper electrode with a loading of 0.3 and 0.5 mg Ptcm~(-2) was evaluated in proton exchange membrane single cell fuel cell using H_2/O_2. The single cells exhibited a peak power density of 600 and 800mWcm~(-2) with catalyst loadings of 0.3 and 0.5 mg Ptcm~(-2), respectively with H_2/O_2 at 80℃, using Nafion-212 electrolyte. In order to understand the intrinsically higher fuel cell performance, the elec-trochemically active surface area was estimated by the cyclic voltammetry of the Pt/MWCNTs/carbon paper.