掺杂纳米SiO_2的PVDF-g-PSSA质子交换膜  

PVDF-g-PSSA and SiO_2 Composite Proton Exchange Membranes

作　　者：申益[1] 席靖宇[1] 邱新平[1] 朱文涛[1] 陈立泉[1] 

机构地区：[1]清华大学化学系有机光电子与分子工程重点实验室,北京100084

出　　处：《化学学报》2007年第14期1318-1324,共7页Acta Chimica Sinica

基　　金：国家973基础研究项目(No.2002CB211803);国家自然科学基金(No.50606021)资助项目

摘　　要：以聚偏氟乙烯(PVDF)为骨架,采用溶液接枝苯乙烯磺酸,合成了掺杂纳米SiO2颗粒的复合质子交换膜(PVDF/xSiO2-g-PSSA).利用红外光谱、热失重分析方法、扫描电镜,对膜的结构、热稳定性、表面及断面形态进行了表征.考察了膜的吸水率、电导率、甲醇渗透性等性质.结果表明,纳米SiO2颗粒能提高膜的阻醇性能,掺杂质量分数10%的适量SiO2颗粒所得的复合膜的甲醇渗透系数达1.0×10-7cm2/s,低于聚偏氟乙烯接枝苯乙烯磺酸(PVDF-g-PSSA)膜的1.7×10-7cm2/s,仅为Nafion-117的渗透系数的二十分之一.PVDF/10%SiO2-g-PSSA复合膜具有较高的选择性,在直接甲醇燃料电池中具有良好的应用前景.A novel kind of composite proton exchange membrane was prepared by doping the nano-SiO2 into poly（vinylidene fluoride） grafted polystyrene sulfonated acid （PVDF/xSiO2-g-PSSA）. The structure and stability of the membranes were characterized with the IR spectra and thermal gravity analysis （TGA）. The morphology of the surface and the dispersion of elements in the cross section of the membrane were observed by the scanning electron microscope （SEM）. The water-uptake, proton conductivity and methanol permeability of the membranes were measured. The results showed that the nano-SiO2 could slow the methanol permeation; the permeability coefficient of the composite membrane with SiO2 （w= 10%） was up to 1.0 × 10^-7 cm^2/s, which is lower than that of PVDF-g-PSSA and just one twentieth of that of Nafion-117. This kind of composite membranes has high selectivity and shows a promising practical value in direct methanol fuel cells （DMFC）.

关 键 词：直接甲醇燃料电池 质子交换膜 聚偏氟乙烯接枝苯乙烯磺酸 二氧化硅 甲醇渗透率 

分 类 号：TM911.4[电气工程—电力电子与电力传动]