PDF《SPES/PWA/SiO2 复合质子交换膜的性能》

[Article] www.

whxb.pku.edu.cn 物理化学学报(Wuli Huaxue Xuebao) Acta Phys. 鄄Chim. Sin., 2010, 26(11): 2967-2974 November Received: June 2, 2010;

Revised: August 25, 2010;

Published on Web: October 8, 2010. 鄢Corresponding author. Email: [email protected];

Tel: +86鄄712鄄2345464. The project was supported by the Natural Science Foundation of Hubei Province, China (2009CDZ016). 湖北省自然科学基金(2009CDZ016)资助项目 Editorial office of Acta Physico鄄Chimica Sinica SPES/PWA/SiO2 复合质子交换膜的性能 龚春丽

1 周毅1闫礼成

2 文胜1,2,鄢 郑根稳

1 (1 孝感学院化学与材料科学学院, 湖北 孝感 432000;

2 湖北大学材料科学与工程学院, 武汉 430062) 摘要: 以磺化聚醚砜(SPES)为基体, 以不同比例的 SiO2 溶胶与磷钨酸(PWA)为掺杂物, 制备了一种有望用于直 接甲醇燃料电池(DMFC)的新型 SPES/PWA/SiO2 有机鄄无机复合膜, 并经热失重分析(TGA)、 差示扫描量热仪 (DSC)、 扫描电镜(SEM)鄄X 射线能谱分析(EDX)等对膜的结构和性能进行了表征, 探讨了复合膜用作质子交换膜 的可能性. 结果表明: 复合膜较纯 SPES 膜具有更高的热稳定性、 玻璃化转变温度和吸水率;

虽然在室温和电池 操作温度(80 益)下, 复合膜的拉伸强度均低于纯 SPES 膜, 但即使当 SiO2 含量高达 20%(w)时, 复合膜的拉伸强度 仍高于 Nafion

112 膜的;

SEM 图片显示 SiO2 和PWA 在膜中分布均匀, 这将有利于连续质子传输通道的形成. 对于 SiO2 含量为 15%(w), PWA 含量为 6%(w)的复合膜, 其室温质子传导率达到了 0.034 S ・ cm-1 , 与Nafion

112 膜的相当, 但其甲醇渗透率明显降低, 仅为商用 Nafion

112 膜的七分之一左右, 这表明该复合膜在直接甲醇燃料 电池中具有良好的应用前景. 关键词: 直接甲醇燃料电池;

磺化聚醚砜;

二氧化硅;

磷钨酸;

复合膜 中图分类号: O646 Properties of SPES/PWA/SiO2 Composite Proton Exchange Membranes GONG Chun鄄Li1 ZHOU Yi1 YAN Li鄄Cheng2 WEN Sheng1,2,鄢ZHENG Gen鄄Wen1 (1 Faculty of Chemistry and Materials Science, Xiaogan University, Xiaogan 432000, Hubei Province, P. R. China;

2 Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062, P. R. China) Abstract: Novel sulfonated poly(ether sulfone) (SPES)/phosphotungstic acid (PWA)/silica organic鄄inorganic composite membranes for application in direct methanol fuel cells (DMFCs) were prepared by doping SiO2 sol and PWA into SPES matrix. The structure and performance of the obtained membranes were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy鄄energy dispersive X鄄ray spectroscopy (SEM鄄EDX), etc. Compared with the pure SPES membrane, SiO2 and PWA doping led to higher thermal stabilities, a higher glass transition temperature (Tg), and higher water uptake. At

20 益and a fuel cell operating temperature of

80 益, the tensile strength of all the composite membranes was lower than that of the SPES membrane. However, even when the content of SiO2 was as high as 20% (w), the composite membrane still possessed a higher strength than a Nafion

112 membrane. The morphology of the composite membranes indicated that SiO2 and PWA were uniformly distributed throughout the SPES matrix, which may facilitate proton transport. The proton conductivity of the composite membrane (SPES鄄P鄄S 15%: 15% (w) SiO2 and 6% (w) PWA) reached 0.034 S ・ cm-1 , which was similar to that of the Nafion