Progress towards new materials for proton exchange membranes (pem)s in fuel cells (FC)s

摘要

Proton exchange membrane (PEM) fuel cells (FC)s are electrochemical devices that convert the chemical energy of a fuel directly and efficiently into electrical and thermal energy. The presently used Nafion* type perfluorosulfonic acid polymers have some excellent properties along with a few shortcomings. One of the most serious disadvantages preventing widespread use for PCs is the high cost of the material. Another is the unacceptable methanol permeability in the direct methanol FC application. We have been investigating several aspects of FC materials. The first aspect is an investigation of the polymer-solvent interactions that occur during film preparation. During PEM preparation from sulfonated polymer, thin uniform films are usually prepared by easting the polymer solutions from solvents. The literature reports large variations in the proton conductivities of similarly sulfonated polymers, depending on how the PEM was prepared. We have observed that chemical interactions with the various solvents used in the process of PHM preparation may be one of the reasons for He large discrepancies in proton conductivity data existing in the literature.