TiO2 from colloidal dispersion as support in Pt/TiO2 nanocomposite for electrochemical applications

Abstract

TiO2 powder was synthesized by a forced hydrolysis process and used for the synthesis of Pt/TiO2 composite that is to be foreseen as an advanced electrode material. Pt was incorporated into the synthesized TiO2 from a Pt colloidal dispersion as a precursor prepared by a microwave-assisted polyol process. Physicochemical properties of TiO2 and TiO2-supported Pt were investigated by scanning electron micros-copy, dynamic light scattering and X-ray spectroscopy and diffraction techniques. The properties of Pt/TiO2 composite are correlated to the basic voltammetric response of its thin-layer form. It was found that subsequent thermal treatment of synthesized TiO2, which caused crystal-lization into mainly rutile phase, is required for appropriate Pt incorporation. Although being appropriately loaded by Pt, and the voltammetric response is typical for Pt-based material, the voltammetry of Pt/TiO2 corresponded to much lower loadings. The possibility for Pt particles to be trapped inside TiO2 agglomerates is indicated. The catalyst usage from the synthesized Pt/TiO2 was found quite moderate due to this trapping.