| 摘要 |
<p>Membrane electrode assemblies (MEA) comprise an asymetric membrane composite, a cathode and an anode in electrical contact with the composite to form solid polymer electrolytes. The asymetric membrane composites comprise a thin, continuous, nonporous, but water and proton permeable polymeric film layer, an adjacent thicker stratum or layer consisting of a porous support backing and a catalyst impregnated mainly in the porous support region. The catalyst may be one, for example, that is suitable for the oxidation ofunreacte alcohol. The MEAs may be employed in both energy producing electrochemical cells, e.g. fuel cells and energy consuming electrochemical cells for the synthesis of chemicals. The MEAs may be adapted for direct feed methanol fuel cells and are especially useful in eliminating crossever of unreacted methanol to the cathode and unwanted voltage reduction.</p> |
