Chen Yuning, Zhang Shouhai, Liu Qian, Jian Xigao
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, High Performance Polymer Engineering Research Center Dalian 116024 China
RSC Adv. 2019 Aug 20;9(45):26097-26108. doi: 10.1039/c9ra05111b. eCollection 2019 Aug 19.
Novel poly(phthalazinone ether ketone)-based amphoteric ion exchange membranes with improved ion selectivity, stability and water transport resistance were prepared for vanadium redox flow battery (VRB) applications. The preparation method ensured the absence of electrostatic interaction. A small amount of sulfonated poly(phthalazinone ether ketone) (SPPEK) with different ion exchange capacity (IEC) values was mixed with brominated poly(phthalazinone ether ketone) (BPPEK) to prepare base membranes with the solution casting method, and they were aminated in trimethylamine to obtain the resulting membranes (Q/S-, represents the IEC value of SPPEK). Compared with the AEM counterpart (QBPPEK) prepared from the amination of the BPPEK membrane, Q/S-1.37 showed lower swelling ratio and area resistance (). The value of Q/S-1.37 (0.58 Ω cm) was close to that of Nafion115. The VO and V permeability values of Q/S- were 96.7-97.6% and 98.5-99.2% less than those of Nafion115, respectively, demonstrating the excellent ion selectivity of Q/S-. Compared with Nafion115 and QBPPEK, Q/S-1.37 displayed 90.0% and 92.1% decrease in the static water transport volume and 93.2% and 66.7% decrease in the cycling transport rate, respectively, revealing good water transport resistance. Compared with Nafion115, Q/S-1.37 exhibited an increase of 1.0-5.7% in the coulombic efficiency (CE) and an increase of 2.5-8.7% in the energy efficiency (EE) at 20-200 mA cm. Q/S- showed better chemical stability in VO solutions than QBPPEK. VRB with Q/S-1.37 could be steadily operated for 400 h without sudden capacity and efficiency drop, while VRB with QBPPEK could hold for only around 250 h. Q/S-1.37 retained higher CE, EE and capacity retention than Nafion115, displaying good long-term stability. Thus, the Q/S- are promising for use in commercial VRBs.
制备了具有改进的离子选择性、稳定性和抗水传输性能的新型聚（酞嗪酮醚酮）基两性离子交换膜，用于钒氧化还原液流电池（VRB）。该制备方法确保不存在静电相互作用。将少量具有不同离子交换容量（IEC）值的磺化聚（酞嗪酮醚酮）（SPPEK）与溴化聚（酞嗪酮醚酮）（BPPEK）混合，采用溶液浇铸法制备基膜，并在三甲胺中进行胺化以获得所得膜（Q/S-，代表SPPEK的IEC值）。与由BPPEK膜胺化制备的AEM对应物（QBPPEK）相比，Q/S-1.37显示出更低的溶胀率和面积电阻（）。Q/S-1.37的 值（0.58 Ω·cm）接近Nafion115的值。Q/S-的VO和V渗透率值分别比Nafion115低96.7 - 97.6%和98.5 - 99.2%，表明Q/S-具有优异的离子选择性。与Nafion115和QBPPEK相比，Q/S-1.37的静态水传输体积分别降低了90.0%和92.1%，循环传输速率分别降低了93.2%和66.7%，显示出良好的抗水传输性能。与Nafion115相比，Q/S-1.37在20 - 200 mA/cm²时的库仑效率（CE）提高了1.0 - 5.7%，能量效率（EE）提高了2.5 - 8.7%。Q/S-在VO 溶液中比QBPPEK表现出更好的化学稳定性。使用Q/S-1.37的VRB可以稳定运行400小时而不会突然出现容量和效率下降，而使用QBPPEK的VRB只能维持约250小时。Q/S-1.37比Nafion115保留了更高的CE、EE和容量保持率，显示出良好的长期稳定性。因此，Q/S-有望用于商业VRB。
