Electrochemical preparation and structural characterization of platinum thin film on a polypyrrole film modified ITO electrode.

Platinum nanostructures have been fabricated by electrochemical deposition of platinum onto indium tin oxide (ITO) glass substrate modified with thin polypyrrole film. The crystal size and the number density of the platinum nanoparticles have been examined by varying several deposition parameters, including the thickness of the PPy film and the current densities for platinum deposition. Optimal conditions for uniform growth of nanoparticles well-dispersed on the ITO have been determined, along with insight into the mechanism of crystal growth. The PPy film thickness principally affect the size and number density of the nanoparticles, while the platinum deposition current densities could be used to regulate the shape of the nanoparticles. In addition, the flower-like platinum nanoparticles showed high catalytic activity on electrochemical oxidation of methanol, and its activity was measured to be approximately 1.9 times that of bare platinum.