Functionalized zeolite A–nafion composite membranes for direct methanol fuel cells

A series of composite membranes based on zeolite A and Nafion 117 have been fabricated for direct methanol fuel cells. The external surface of zeolite A has been modified to enhance the interface bonding between inorganic zeolite crystals and Nafion ionomer. The modified zeolite samples have been characterised using a combination of thermal analysis and spectroscopic techniques. Methanol permeability of Nafion 117 could be reduced by as much as 86% by incorporating functionalised zeolite NaA crystals into the membrane. The effect of different functionalisation level is discussed.