Improved electrochemical performance of composite anion exchange membranes for fuel cells through cross linking of the polymer chain with functionalized graphene oxide
Improved electrochemical performance of composite anion exchange membranes for fuel cells through cross linking of the polymer chain with functionalized graphene oxide
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DOI：
10.1016/j.memsci.2020.118385
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发表时间：
2020-10-01
影响因子：
9.5
通讯作者：
Yoo, Dong Jin
中科院分区：
文献类型：
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作者：
Chu, Ji Young;Lee, Kyu Ha;Yoo, Dong Jin
通过在季铵化聚芳醚（QPAE）无规共聚物中引入季铵功能化氧化石墨烯（Q-GO），制备了具有优异的氢氧化物导电性和碱性化学稳定性的新型阴离子导电纳米复合膜。以（3-氨丙基）三乙氧基硅烷（APTS）和（3-溴丙基）三甲基溴化铵（PTMA）为主要季铵化试剂，合成了含有氨基硅烷单元的Q-GO，该氨基硅烷单元可在聚合物基体中诱导离子簇的形成。采用H-1 NMR、FT-IR、FE-SEM、XPS和SAXS等手段对聚合物和无机纳米填料的化学结构和形态进行了表征。GO-（APTS-c-PTMA），即Q-GO，用于扩大离子转移位点和改善膜的物理化学稳定性。研究了GO-（APTS-c-PTMA）含量对阴离子交换膜电化学性能、热/机械性能和化学稳定性的影响。聚合物基质和Q-GO之间的π-π键导致复合膜中改进的尺寸稳定性和机械性能。QPAE/GO-（APTS-c-PTMA）0.7wt%膜在90 ° C下显示出114.2mS cm（-1）的最高氢氧化物电导率和1.45mmol g（-1）的离子交换容量，这是原始膜（在90 ° C下为55.1mS cm（-1））的2.07倍。此外，QPAE/GO-（APTS-c-PTMA）0.7重量%作为AEM的单电池性能显示出在70 ℃下135.8 mW cm-2的优异的最大功率密度。
Novel anion conductive nanocomposite membranes with superb hydroxide conductivity and chemical durability in alkaline conditions were prepared by the introduction of quaternary ammonium functionalized graphene oxide (Q-GO) into quaternized poly(arylene ether) (QPAE) random copolymer. Q-GO containing amino silane units, which induce ion cluster formation in the polymer matrix, was synthesized using (3-aminopropyl)triethoxysilane (APTS) and (3-bromopropyl)trimethyl ammonium bromide (PTMA) as the main quaternization reagents. The chemical structures and morphologies of the polymers and inorganic nanofillers were characterized by H-1 NMR, FT-IR, FE-SEM, XPS, and SAXS. GO-(APTS-c-PTMA), the so called Q-GO, was used to expand the ion transfer sites and improve the physicochemical stability of the membrane. The electrochemical properties, thermal/mechanical properties, and chemical stabilities of the anion exchange membranes (AEMs) were investigated in accordance with different contents of GO-(APTS-c-PTMA). The pi-pi bonds between the polymer matrix and the Q-GO resulted in improved dimensional stability and mechanical properties in the composite membrane. The QPAE/GO-(APTS-c-PTMA) 0.7 wt% membrane showed the highest hydroxide conductivity of 114.2 mS cm(-1) at 90 degrees C with an ion exchange capacity of 1.45 mmol g(-1), which is 2.07 times higher than the pristine membrane (55.1 mS cm(-1) at 90 degrees C). Furthermore, the single-cell performance of the QPAE/GO-(APTS-c-PTMA) 0.7 wt% as an AEM showed an excellent maximum power density of 135.8 mW cm(-2) at 70 degrees C.