Improvement of direct methanol fuel cell performance using a novel mordenite barrier layer

Abstract

The selective incorporation of a functionalised inorganic component at the interface between the Nafion membrane and the catalyst is demonstrated to increase the power density of a direct methanol fuel cell by 57% with no other change in operating conditions. The simple addition of 0.5 wt% zeolite (mordenite) in the Nafion ‘ink,’ which is used as a glue to fix the precast Nafion membrane onto the catalyst/gas diffusion layer, provides an organophobic quality to the MEA which enhances performance and durability. The targeted addition of such small amounts of the ‘organophobe’ at the interface where the chemical effect is required is a novel approach to improving DMFC MEA's and means that the usual trade-off between methanol permeability and proton conductivity is not observed as proton conductivity is maintained while methanol crossover is reduced.