- The electrolyte membrane for low temperature fuel cells used by most R&D groups is Nafion or one of its relatives, i.e., a teflon-based sulfonated polymer that transports protons from the anode to the cathode.
- Disadvantages of Nafion:
- must remain well-hydrated (wet) to maintain reasonable protonic conductivity i.e. it limits its operating temperature to a maximum of about 80°C at ambient pressure
- low physical strength of the polymer limits how thin it can be in practical applications, thus also limiting the membrane conductance
- soluble in methanol, so in methanol fuel cells, the fuel must be diluted to only about 5% or below when it reaches the membrane to avoid membrane breakdown.
- At CFCI our goal is to systematically vary organic-inorganic hybrid membrane structure with respect to morphology and interaction between the constituents at the interface.
- We will establish connections between microscopic structure and macroscopic properties through synthesis of new organic ionomeric block co-polymers.
- This will enable us to deliberately modulate conductivity and mechanical properties.
- Combining block copolymers with nanoparticles
- will produce high-active surface area catalysts on an electronically-conducting polymeric backbone.
- Addition of the appropriate precursors to a triblock copolymer could produce a high structured electrode. Some ideas of how this may be done are illustrated below
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