Development of Polymer Polyelectrolyte Membranes for Direct Methanol Fuel Cell Application

Abstract

Fuel cells are environmental friendly devices for energy conversion, power generation, and one of the most promising candidates as zero-emission power sources. One of the main drawbacks of the fuel cells is related to the use of the liquid electrolyte. Using a polymer membrane as an electrolyte can solve some limiting requirements of fuel cells. In the resent study, new cheaper polyelectrolyte complex membranes based on renewable natural polymer (chitosan and alginate) was prepared by physically and chemically crosslinking for direct methanol fuel cell (DMFC). Four sets of membranes were prepared. Two of them based on physically crosslinking of chitosan/alginate and sulfonated chitosan/ alginate, and the others based on chemically crosslinking of the same pairs using glutaraldehyde. The membranes were characterized by FTIR to verify complex formation, XRD to observe the effects of modification on crystallinity, TGA to assess the thermal stability, SEM for morphological structure and tensile testing for mechanical stability. Absorption studies were carried out to evaluate the interaction with water and methanol. Finally, methanol permeability of membranes was tested and compared with that published for commercial fuel cell membrane (i.e.; Nafion) Keywords: Fuel cells; Polyelectrolyte membranes; Ion exchange capacity; Chitosan; Alginate; Methanol permeability.