Highly dispersed Pt/C catalysts prepared by the Charge Enhanced Dry Impregnation method

An efficient method to synthesize highly dispersed Pt/carbon xerogel catalysts for Proton Exchange Membrane fuel cell applications is described. The synthesis proceeds via the Charge Enhanced Dry Impregnation method (CEDI), which combines dry impregnation with the Strong Electrostatic Adsorption technique (SEA). The samples prepared via CEDI or SEA techniques were dried and reduced under hydrogen to obtain supported Pt nanoparticles. In order to increase the Pt mass fraction up to 10. wt.%, two successive impregnation-drying-reduction cycles were performed. The synthesized Pt nanoparticles are homogeneously distributed on the carbon support and highly dispersed (mean Pt nanoparticle size of ca. 2. nm). The CEDI method is ideally suited to avoid Pt losses during the catalyst preparation.