Nafion®/mordenite composite membranes for improved direct methanol fuel cell performance

Composite polymer proton exchange membranes (PEM) were prepared by solution recasting. The composite membranes formed are based on Nafion incorporating a silane functionalized zeolite, mordenite, as an additive. The composite membranes were placed within a single cell DMFC and compared to an MEA featuring a standard Nafion 125 μm membrane. The impact of mordenite particle size, the choice of the silane functionalizing agent and the membrane preparation procedure are investigated. A composite ion exchange membrane which featured Nafion and a ground mordenite which was functionalized using glycidoxypropyltrimethoxysilane achieved a power density that outperformed a standard Nafion MEA under all conditions.