Interdisciplinary Graduate School of Medicine and Engineering, ‡Fuel Cell Nanomaterials Center, and §Clean Energy Research Center, University of Yamanashi , 4 Takeda, Kofu 400-8510, Japan.
ACS Appl Mater Interfaces. 2014 Oct 8;6(19):17044-52. doi: 10.1021/am5046586. Epub 2014 Sep 25.
A novel series of aromatic block copolymers composed of fluorinated phenylene and biphenylene groups and diphenyl ether (QPE-bl-5) or diphenyl sulfide (QPE-bl-6) groups as a scaffold for quaternized ammonium groups is reported. The block copolymers were synthesized via aromatic nucleophilic substitution polycondensation, chloromethylation, quaternization, and ion exchange reactions. The block copolymers were soluble in organic solvents and provided thin and bendable membranes by solution casting. The membranes exhibited well-developed phase-separated morphology based on the hydrophilic/hydrophobic block copolymer structure. The membranes exhibited mechanical stability as confirmed by DMA (dynamic mechanical analyses) and low gas and hydrazine permeability. The QPE-bl-5 membrane with the highest ion exchange capacity (IEC = 2.1 mequiv g(-1)) exhibited high hydroxide ion conductivity (62 mS cm(-1)) in water at 80 °C. A noble metal-free fuel cell was fabricated with the QPE-bl-5 as the membrane and electrode binder. The fuel cell operated with hydrazine as a fuel exhibited a maximum power density of 176 mW cm(-2) at a current density of 451 mA cm(-2).
一种新型的芳香族嵌段共聚物，由氟化的联苯和联苯基团以及二苯醚（QPE-bl-5）或二苯硫醚（QPE-bl-6）基团作为季铵基团的支架组成。嵌段共聚物通过芳族亲核取代缩聚、氯甲基化、季铵化和离子交换反应合成。嵌段共聚物可溶于有机溶剂，并通过溶液浇铸提供薄而柔韧的膜。该膜具有基于亲水/疏水嵌段共聚物结构的良好分离相形态。DMA（动态机械分析）和低气体和联氨渗透性证实了膜具有机械稳定性。具有最高离子交换容量（IEC=2.1 mequiv g(-1))的 QPE-bl-5 膜在 80°C 的水中表现出 62 mS cm(-1)的高氢氧根离子电导率。使用 QPE-bl-5 作为膜和电极粘合剂制造了无贵金属燃料电池。以联氨为燃料的燃料电池在 451 mA cm(-2)的电流密度下表现出 176 mW cm(-2)的最大功率密度。
