Design of Thin-layered membrane electrode assembly prepared by sputtering method for Direct Methanol Fuel Cells

摘要

Superior performance of direct methanol fuel cells (DMFCs) may be obtained by localized catalyst loading on reaction sites and reduction of charge transfer and diffusion resistances. These may be realized by thin-layered membrane electrode assemblies (MEAs) for which new component materials and a new catalyzed method are used. In this study, gas diffusion electrodes consisted of sputter-deposited Pt as a catalyst layer and "carbon silk" as a diffusion layer are evaluated as cathodes for DMFCs. A cathode prepared by sputter-deposited Pt on spreading the mixture of Nafion, carbon and butyl acetate (NCB) solution showed an increase in current density and mass activity for the oxygen reduction reaction. Consequently, effects of NCB on cathodic polarization are explained by supplying protonic and electronic conduction paths to electrochemically inactive Pt with oxygen diffusion path. Mass activities using NCB were found about five times higher than a sputter-deposited Pt Cathodes without NCB.