作者:Yun Sheng Ye、Ming Yao Cheng、Ji Yong Tseng、Gao-Wei Liang、John Rick、Yao Jheng Huang、Feng Chih Chang、Bing Joe Hwang
DOI:10.1039/c0jm02878a
日期:——
New proton conducting membranes, exhibiting a high proton conductivity (10−2 S cm−1, without humidification at 160 °C), based on the ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm-BF4) were investigated. The incorporation of a similar initial IL loading was found to reduce the proton conductivity loss of a sulfonated polydiacetylene based membrane, i.e. SPDA70-IL70 by 19.2% and IL-based Nafion by 64.6%; additionally, the SPDA70-IL70 was able to maintain a proton conductivity of more than 10−3 S cm−1 after centrifugation. The introduction of both a cross-linked structure and a high degree of sulfonation into the polymer matrix, resulted in significant improvements to the membranes' thermal properties, the dispersion of ionic domains, and the retention of IL—together with a reduction of proton conductivity loss. The membranes, which have a high degree of sulfonation with thermally cross-linkable diacetylene in the polymer's main chain, avoid the drawback of poor miscibility commonly associated with sulfonated polymers and cross-linking agents. When the composite membrane was used in a H2/O2 fuel cell without humidification at 100 °C, a power density > 250 mA cm−2 was achieved together with a maximum current denisty of 122 mW cm−2.
研究了基于离子液体(IL)1-丁基-3-甲基咪唑四氟硼酸盐(BMIm-BF4)的新型质子导电膜,该膜在160 °C下的质子导电率为10−2 S cm−1(无需湿润)。发现相似初始IL负载的引入能够减少磺化聚二乙炔膜(即SPDA70-IL70)的质子导电率损失19.2%,以及IL基Nafion的质子导电率损失64.6%;此外,SPDA70-IL70在离心后能够保持超过10−3 S cm−1的质子导电率。将交联结构和高程度的磺化引入聚合物基体,显著改善了膜的热性能、离子域的分散性以及IL的保持能力,同时降低了质子导电率的损失。这些膜具有高程度的磺化,且聚合物主链中含有热可交联的二乙炔,避免了磺化聚合物和交联剂常见的低相容性缺陷。在100 °C下,复合膜在无湿润条件下用于氢/氧燃料电池时,达到了超过250 mA cm−2的功率密度,以及最大电流密度为122 mW cm−2。