在设计聚电解质膜(PEM)材料方面的复兴已经提出了网格规模的电化学储能装置。在这里,我们报告了证实离子域微观结构修饰和远爪双哌啶官能化氧化石墨烯(GO)的插层的协同影响的研究,以从磺化的聚(2,6-二甲基-1,4-亚苯基醚)(sPPE)制造稳定的双功能膜,用于高效的蒽环类碱性氧化还原液流电池。通过双功能离子导电基质,精心解决了对基于碳氢化合物的PEM中的碱性稳定性和-OH电导率困境的持久追求。对sPPE中亲水结构域分布的优先研究表明,具有高微相均匀性,在恒电流充放电(GCD)分析过程中可以实现更高的比容量保留。此外,通过改善包含双哌啶鎓的氧化石墨烯(bis-QGO)的氧化还原电解质-膜界面亲和力来克服低容量问题。因此,在双QGO的1.0和2.0重量%插层下,双功能聚电解质膜(BFPM)赋予最低的过电位93mV(对于BFPM-1.0)和〜100mV(对于BFPM-2.0),比Nafion-117低43和40%(即,~164mV)。此外,BFPM的效率,viz.,库仑,电压,和能源效率,是95-98%,85%,在20mAcm-2时分别≥80%。在长时间循环操作中,GCD曲线证明在450个循环中保持了99%的效率,并说明了可重复的速率能力。最后,BFPM的极化研究显示,峰值功率密度(87.5mWcm-2)比Nafion-117(~57mWcm-2)高54%。我们相信,这种战略设计方法可以提供更新和简单的途径,在低插层负载下利用高性能BFPM,用于碱性电化学储能和相关应用。
The resurgence in designing polyelectrolyte membrane (PEM) materials has propound grid-scale electrochemical energy storage devices. Herein, we report on studies corroborating the synergistic influence of ionic domain microstructure modification and intercalation of telechelic bis-piperidinium-functionalized graphene oxide (GO) to fabricate stable bifunctional membranes from sulfonated poly(2,6-dimethyl-1,4-phenylene ether) (sPPE) for efficient anthrarufin-based alkaline redox flow batteries. A critically long-lasting quest on alkaline stability and -OH conductivity dilemma in hydrocarbon-based PEMs is meticulously resolved via a bifunctional ion-conducting matrix. Preferential studies on hydrophilic domain distribution in sPPE suggest that, with high microphase homogeneity, higher specific capacity retentions are achievable during galvanostatic charge-discharge (GCD) analysis. Moreover, the low-capacity issues were overcome by improving the redoxolyte-membrane interface affinities incorporating bis-piperidinium-bearing graphene oxide (bis-QGO). Consequently, at 1.0 and 2.0 wt % intercalation of bis-QGO, the bifunctional polyelectrolyte membranes (BFPMs) impart lowest overpotentials of 93 mV (for BFPM-1.0) and ∼100 mV (for BFPM-2.0) which are ∼43 and 40% lower than that of Nafion-117 (i.e., ∼164 mV). Furthermore, the efficiency of BFPMs, viz., the Coulombic, voltage, and energy efficiencies, was ∼95-98%, ∼85%, and ≥80% at 20 mA cm-2, respectively. In long-cycling operations, the GCD profile evidenced ∼99% efficiency retention over 450 cycles and illustrated reproducible rate capability. Finally, the polarization studies of BFPMs revealed ∼54% higher peak power density (87.5 mW cm-2) delivery than Nafion-117 (∼57 mW cm-2). We believe that this strategic designing approach could offer newer and simple avenues to avail high-performance BFPMs at low intercalation loads for alkaline electrochemical energy storage and related applications.