Low content Pt based catalysts (Pt-Mx, Mx: SnO2, Sn) were prepared by microwave assisted-thermal synthesis. Pt-SnO2/C catalyst showed good performance for methanol oxidation reaction. Besides, Pt1Sn1/C showed good performance for catalyzing the oxygen reduction reaction. The catalysts were characterized structurally by X-ray diffraction and transmission electron microscopy techniques. It was possible to observe the presence of nanoparticles obtained by the synthesis method used in this work. The chemical composition of every material was determined by energy dispersive spectroscopy analysis. The electrochemical characterization of the electrocatalytic materials was carried out in acid medium by cyclic voltammetry and rotating disk electrode techniques. Pt-SnO2/C and Pt1Sn1/C were compared with commercial PtRu/C and Pt/C catalysts respectively. Pt-SnO2/C showed better electrochemical characteristics than commercial PtRu/C for performing the methanol oxidation reaction (MOR). Pt1Sn1/C showed an exchange current density two orders of magnitude higher than commercial Pt/C for performing the oxygen reduction reaction (ORR). The materials were evaluated in an experimental direct methanol fuel cell (DMFC) operating during 10 hours. The electric power density loss showed by the DMFC made with commercial catalysts (PtRu/C and Pt/C) was 67% while the DMFC made with Pt-SnO2/C and Pt1Sn1/C showed an electric power loss ca. 16%. It means that the catalysts synthesized in this work can be considered as good candidates for experimental direct methanol fuel cells.
TiO2 Nanotube-Carbon (TNT-C) as Support for Pt-based Catalyst for High Methanol Oxidation Reaction in Direct Methanol Fuel Cell
