Novel Triple Tertiary Amine Polymer-Based Hydrogen Bond Network Inducing Highly Efficient Proton-Conducting Channels of Amphoteric Membranes for High-Performance Vanadium Redox Flow Battery
Novel Triple Tertiary Amine Polymer-Based Hydrogen Bond Network Inducing Highly Efficient Proton-Conducting Channels of Amphoteric Membranes for High-Performance Vanadium Redox Flow Battery
复制标题
新型三叔胺聚合物基氢键网络诱导高性能钒氧化还原液流电池的两性膜高效质子传导通道
DOI：
10.1021/acsami.8b18617
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发表时间：
2019
影响因子：
9.5
通讯作者：
Gaohong He
中科院分区：
文献类型：
--
作者：
Huaqing Zhang;Xiaoming Yan;Li Gao;Lei Hu;Xuehua Ruan;Wenji Zheng;Gaohong He
通过将三叔胺接枝的聚（2,6-二甲基-1,4-苯醚）（PPO-TTA）与磺化聚醚醚酮（SPEEK）共混，设计了一种用于钒氧化还原液流电池的新型两性膜。叔胺基与磺酸基结合形成“酸碱对”效应，多余的非键合胺基可被质子化。两者构成氢键网络，有利于质子传导，同时由于降低的溶胀比和唐南效应而阻碍钒的渗透性。所有这些都有助于提高膜的离子选择性，同时保持离子电导率。与其他两性和SPEEK基膜相比，该膜表现出优异的性能。含有 15% PPO-TTA 的两性膜具有 3.4 × 10–9cm2s–1 的超低钒渗透率和 0.39 Ω cm–2 的低面电阻。因此，用这种膜组装的电池表现出远优于SPEEK和Nafion 212的优异性能。电池的库仑效率和能量效率在40-200 mA cm-2时分别为94.3-98.3和90.3-77.1%，并且在200次循环后没有明显下降。这一性能在近年来报道的两性膜和SPEEK膜中处于较高水平。电池的开路电压可维持长达 165 小时。此外，通过有效阻挡钒离子，提高了膜的化学稳定性。
A novel amphoteric membrane was designed by blending triple tertiary amine-grafted poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-TTA) with sulfonated poly(ether ether ketone) (SPEEK) for vanadium redox flow batteries. An “acid–base pair” effect is formed by the combination of the tertiary amine group and sulfonic group, and extra nonbonding amine groups could be protonated. Both of them constitute a hydrogen bond network, which facilitates proton conduction and also hinders vanadium permeability because of the lowered swelling ratio and Donnan effect. All these contribute to improve the ion selectivity of the membrane while maintaining ionic conductivity. Compared with other amphoteric and SPEEK-based membranes, the membrane exhibits an excellent performance. The amphoteric membrane containing 15% PPO-TTA exhibits an ultralow vanadium permeability of 3.4 × 10–9cm2s–1and a low area resistance of 0.39 Ω cm–2. Consequently, the cell assembled with this membrane shows excellent performances far superior to SPEEK and Nafion 212. The Coulombic efficiency and energy efficiency of the cell are 94.3–98.3 and 90.3–77.1% at 40–200 mA cm–2, respectively, and have no significant reductions after 200 cycles. This performance is at a high level among the amphoteric and SPEEK-based membranes reported in recent years. The cell’s open circuit voltage is maintained for up to 165 h. In addition, the membrane’s chemical stability is improved by the effective barrier to the vanadium ion.