Sputter deposition of highly dispersed platinum nanoparticles on carbon nanotube arrays for fuel cell electrode material

Vertically aligned carbon nanotube (VACNT) arrays were synthesized using a microwave-plasma-enhanced chemical vapor deposition (MPECVD) system for polymer electrolyte fuel cell (PEMFC) electrode applications. Platinum nanoparticles (Pt NPs) were deposited on as grown VACNT arrays by a DC sputtering system. Pt NPs in the size range of 3-5 nm were formed on the CNT surfaces. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and electron microscopy were employed to study the structural and chemical bonding changes post deposition of Pt NPs. Variable particle density along the nanotube length was observed with cluster formation on tip ends and individual Pt NPs forming farthest away from tip ends. Change observed in the C1s and N1s core level spectra and its possible implications on the Pt/VACNT properties were also discussed. (C) 2009 Elsevier B.V. All rights reserved.