Highly dispersed platinum nanoparticles on carbon nanocoils and their electrocatalytic performance for fuel cell reactions

Highly graphitic carbon nanocoils (GCNC) were synthesized through the catalytic graphitization of carbon microspheres obtained by the hydrothermal carbonization of different saccharides (sucrose, glucose and starch) and were used as a support for Pt nanoparticles. The Pt nanoparticles were deposited by means of a polymer mediated-polyol method. The Pt catalysts were characterized both physically (XRD. TEM, HRTEM and XPS) and electrochemically (electrooxidation of methanol in an acid medium). The electrocatalysts thus prepared show a high dispersion of Pt nanoparticles, with diameters in the 3.0-3.3 nm range and a very narrow particle size distribution. These catalytic systems possess high electroactive Pt surface areas (up to 85 m(2) g(-1) Pt) and they exhibit large catalytic activities towards methanol electrooxidation (up to 201 A g-1 Pt). Moreover, they have a high resistance against oxidation, which is considerably greater than that of the Pt/Vulcan system. (C) 2008 Elsevier Ltd. All rights reserved.