Characteristics of Platinum (Pt) on zeolite electrocatalysts have been experimentally studied to understand its potentials for direct methanol fuel cell (DMFC) applications. The Y zeolite was chosen as a Pt-supported substrate with 1.5 wt% Pt loading on zeolite. The Pt nanoparticle size and local atomic structure in both electrochemical and gas cell treatments were investigated by using X-ray absorption spectroscopy (XAS), in particular the extended X-ray adsorption fine structure (EXAFS) method, and the electrocatalytic activity of Pt nanoparticle on Y zeolite was determined by cyclic voltammetry (CV). Studies were focused primarily on the observation of hydrogen adsorption and desorption in the hydride region, where the presence of H+ ions was critical for such a process occurred. Analyses have shown that the Pt oxides can be electrochemically reduced, due to a hydrogen ‘spillover’ phenomenon throughout zeolite structures. Based on theoretical estimation and EXAFS data fitting, it was found that the Pt nanoparticle size was 1-1.1 nm from gas cell treatment and 0.7 nm from electrochemical cell treatment. For both scenarios, the number of atoms was estimated 147 and 55 respectively, with 13 atoms at the edge of a Pt cluster for an icosahedron structure. This study demonstrated that the Pt catalytic site on zeolite can be electronically accessible; despite that zeolite is a dc insulator. The Pt/Y zeolite as a new type of electrocatalyst has shown some promises for industrial-scale fuel cell applications, such as reducing higher electrode cost and/or overcoming the difficulty of electrolyte separation
