High performance of carbon nanowall supported Pt catalyst for methanol electro-oxidation

The performance of Pt catalyst supported on carbon nanowall (CNW) and vertically aligned carbon nanofiber (VACNF) for methanol electro-oxidation has been compared. Pt/CNW and Pt/VACNF electrodes were fabricated by growing CNW and VACNF on carbon papers with inductively coupled plasma enhanced chemical vapor deposition, followed by sputter deposition of Pt nanoparticles using a radio-frequency magnetron sputtering system. Scanning electron microscopy and transmission electron microscopy results show that the Pt nanoparticles are homogeneously dispersed on the surface of CNW and VACNF. The histograms of Pt nanoparticle diameter for both electrodes reveal that the Pt/CNW electrode shows a broader particle size distribution. Cyclic voltammetric measurements show that the Pt/CNW electrode has a better electrochemical activity and methanol oxidation property than Pt/VACNF electrode. The unique structure of CNW ensures that Pt/CNW electrode has a faster electron transport rate and shorter electron transport path, which lead to an obvious improvement of electro-catalysis activity compared to the Pt/VACNF electrode and show a further potential application in direct alcohol fuel cells. (C) 2012 Elsevier Ltd. All rights reserved.