FUEL 21 |
| Recent research has shown layer-by-layer (LBL) assembly to be a robust technique for the fabrication of proton exchange membranes (PEMs). The LBL method allows the formation of ultrathin films that have tunable compositions, perm-selective properties and high ionic conductivity values. This work describes the optimization of multilayer systems to develop PEMs for use in low temperature (25°C to 60°C) and low-cost fuel cells. We have recently started to investigate using multilayer technology for direct methanol fuel cells (DMFCs). For optimum performance, PEMs should effectively minimize liquid methanol crossover while maintaining high ion transport. Here we report multilayer systems comprised of a hydrogen-bonding polymers poly(ethylene oxide) (PEO) and poly(acrylic acid) (PAA) assembled over a range of pH values from 2.5 to 3.25. Initial results show ionic conductivity values of ~10-4 S/cm at 25°C and 98% RH. |
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Fuel Cell Technology: Polymer Electrolyte Membrane Fuel Cell Systems
8:25 AM-12:00 PM, Sunday, August 19, 2007 Boston Park Plaza -- Cambridge Rm, Oral
Division of Fuel Chemistry |