Enhanced electrocatalytic performance for methanol oxidation on Pt-TiO2/ITO electrode under UV illumination

Pt is one of the most important electrode materials employed in direct methanol fuel cell, and many efforts have been directed to improving its electrocatalytic performance. In this work, Pt-TiO2 nanocomposites are successfully prepared by a sol-gel method. As revealed by TEM, Pt nanoparticles with an average size of 2.6 nm are well uniformly dispersed on porous TiO2. XRD structural characterization indicates that Pt possesses a face centered cubic crystal structure while TiO2 is in the format of both rutile and anatase phases. The electrochemical performance of as-prepared nanocomposite electrode (Pt-TiO2/ITO) is evaluated by studying the electrocatalytic oxidation of methanol in an alkaline medium with or without UV illumination. Comparative experiments evince that the electrochemical performance of Pt-TiO2/ITO for methanol electrooxidation is markedly improved under UV illumination. Under UV illumination, moreover, the poisoning resistance of Pt-TiO2/ITO for methanol electrooxidation is significantly improved, as supported by the results of time-coursed current measurements. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.