There are two technical obstacles impeding the development of direct methanol fuel cells. The first one is the non-availability of a less costly, but sufficiently electrochemically active, anodic catalyst as an alternative to the most commonly used Pt-Ru mixture. The second problem is that the polymers currently employed as proton exchange membranes, such as Nafion, have substantial methanol crossover resulting in an overall decline of fuel cell power. To overcome the first.problem, we tried to increase the operating temperature up to 200°C. Operating a fuel cell at elevated temperatures can accelerate the electrochemical reactions and depress the electrode poisoning. Thus, the quantity of precious alloys such as Pt/Ru loaded on the electrodes can be reduced, or nonprecious metals can be used instead of Pt/Ru. The use of polyphosphates for proton conduction allows the materials microstruclure to be tailored in order to stabilize water within the polymer framework and achieve high proton conductivity as well as low methanol permeability.
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