PEMFC用PTFE-Nafion复合质子交换膜研究

Research of PTFE-Nafion composite membrane in PEMFC

采用喷涂方法将Nafion溶液与溶剂的混合溶液涂敷在微孔PTFE膜上,制备了PTFE-Nafion复合膜。用复合膜制备了"三合一"膜电极并组装了电池堆进行测试。使用SEM、交流阻抗仪等仪器对复合膜进行测试分析。结果表明:复合膜的氢气透过率在10-8～10-9kPa.cm.S之间;与Nafion212膜相比,复合膜具有更小的面电阻;PTFE基膜、Nafion载量以及表面活性剂等对复合膜性能有显著影响。采用复合膜制备"三合一"膜电极的电池在放电电压0.6V下电流密度达到1.1A/cm2,优于用Nafion212膜制备的膜电极。

PTFE-Nafion composite proton exchange membranes were prepared by spraying modified Nation solution on PTFE membranes. A catalyst coated membrane （CCM） prepared by coating catalyst on the composite membrane and a stack with these CCMs were tested. SEM and AC impedance instrument were used to analyse the composite membranes. The result shows that the PTFE-Nafion composite membrane has more less area resistance than Nation 212 membrane and its H2 permeation rate is about 10^-8 - 10^-9 kPa ocm .S. Moreover, influences of PTFE substrate, Nation loading and surfactant on the performance of composite membranes were studied in details. It is also found that the current density of a single fuel cell assembled with composite membrane reaches 1.1 A/cm^2 at 0.6 V, and this is much higher than that of cell with Nation 212 membrane.