Modified Polymeric Membranes for Direct Alcohol Fuel Cell Applications

Effective membranes for Direct Alcohol Fuel Cell were prepared from two classes of materials. The first one is based on Sulphonated Polyetheretherketon (SPEEK) coated with Carbon Molecular Sieve (CMS) layers and the second class is based on SPEEK/Polyimide (PI) blends. Both approaches led a substantial reduction of Alcoholsol crossover through the membranes, when compared to plain SPEEK and to Nafion 117 membranes. The SPEEK/PI blends had better performance than CMS-coated SPEEK membranes in the DEFC tests. Particularly in DEFC experiments performed at 90 C the SPEEK/PI membranes had a better performance than Nafion 117 membranes due mainly to the effective reduction of ethanol crossover.