In order to improve the selectivity of porous membrane for vanadium redox flow battery (VRB). A polypyrrole (PPy) thin film composite (TFC) membrane was prepared via interfacial polymerization (IP) method and investigated for VRB application. The optimized PPy TFC membrane has shown both low VO²⁺ permeability and low area resistance compared to that of commercial Nafion 115 membrane. The VRB cell assembled with PPy TFC membrane shows a coulombic efficiency (CE) of 98.1% and energy efficiency of 81.0% at 80 mA cm⁻², which is 2.0% and 6.3% higher than that of Nafion 115 membrane, respectively. Furthermore, 93 cycles charge-discharge test proves that the PPy TFC membrane is very stable and the CE decrease rate is only 0.4% for per-cycle on average. Considering the high selectivity, facile preparation procedure and high stability of PPy TFC membrane, it is thus an ideal system for VRB application to overcome the trade-off between vanadium ions permeability and proton conductivity.

为了提高多孔膜对钒氧化还原液流电池（VRB）的选择性。通过界面聚合（IP）方法制备了聚吡咯（PPy）薄膜复合材料（TFC）膜，并研究了其在VRB中的应用。与商用Nafion 115膜相比，优化的PPy TFC膜显示出低VO ²⁺渗透性和低面积电阻。组装有PPy TFC膜的VRB电池在80 mA cm ^-2下的库仑效率（CE）为98.1％，能量效率为81.0％分别比Nafion 115膜高2.0％和6.3％。此外，93个循环的充放电测试证明PPy TFC膜非常稳定，平均每个循环的CE降低率仅为0.4％。考虑到PPy TFC膜的高选择性，简便的制备程序和高稳定性，因此，它是VRB应用中克服钒离子渗透性和质子传导性之间折衷方案的理想系统。