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

tAn efficient method to synthesize highly dispersed Pt/carbon xerogel catalysts for Proton ExchangeMembrane fuel cell applications is described. The synthesis proceeds via the Charge Enhanced DryImpregnation method (CEDI), which combines dry impregnation with the Strong Electrostatic Adsorp-tion technique (SEA). The samples prepared via CEDI or SEA techniques were dried and reduced underhydrogen 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 nanoparticlesare homogeneously distributed on the carbon support and highly dispersed (mean Pt nanoparticle sizeof ca. 2 nm). The CEDI method is ideally suited to avoid Pt losses during the catalyst preparation.