Platinum Decorated Nafion Functionalized Single-Wall Carbon Nanohorns As Catalyst for Proton Exchange Membrane Fuel Cell Applications

Electrode structure plays an important role in the performance of proton exchange membrane fuel cells. To get high electrochemical active area in the electrode, perfluorosulfonate-ionomer is loaded in stage wise. Single-wall carbon nanohorns (SWCNHs) are synthesized by DC arc-discharge method in Helium atmosphere and these synthesized SWCNHs were functionalized with Nafion. Platinum was reduced onto Nafion functionalized SWCNHs through colloidal method. Pt/Nafion-SWCNHs catalysts were prepared by varying deposition times. Detailed characterization of the catalyst was carried out using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), infrared spectroscopy (IR), and Thermo Gravimetric Analysis (TGA). TEM of Pt decorated SWCNHs revealed uniformly dispersed Pt nano particles with an average particle size of 3 nm in the SWCNHs. IR studies of catalyst confirm the presence of Nafion on Pt/Nafion-SWCNHs. Nafion membrane and Pt/Nafion-SWCNHs catalyst were used to construct fuel cell in decal method and tested in fuel cell testing facility. Cyclic voltammetry tests of the catalyst also confirm the high electrochemical active area of the catalyst. Pt reduction onto Nafion functionalized SWCNHs leads to an increase in electrochemically active surface area. High platinum utilization due to increased electrochemical surface area with efficient SWCNHs support of Pt/Nafion-SWCNHs catalyst makes it a promising electrocatalyst for fuel cells.