碱性燃料电池用PFA 基季铵盐类阴离子交换膜的稳定性
摘要
Novel alkaline anion-exchange membranes were synthesized by grafting vinylbenzyl chloride onto pre-irradiated poly(tetrafluoroethylene-<italic>co</italic>-perfluoropropyl vinyl ether) film, followed by quaternization and alkalization. The mechanical stability, thermal stability and chemical stability of the anion-exchange membranes were investigated. The results show that the mechanical stability of the anion-exchange membrane is good enough for fuel cell applications. The anion-exchange membranes were stable when treated in water at 60 °C and in alkaline medium at room temperature. However, due to the direct nucleophilic substitution and Hofmann degradation, the ionic conductivity of the anion-exchange membrane is reduced when the anion-exchange membrane was treated in alkaline medium at 60 °C. Durability of 30 h for an “air-breathing” ethanol single cell at 30 mA cm<sup>-2</sup> was obtained at room temperature with the anion-exchange membrane as the electrolyte.