Wang Fei, Qu Ting, Yang Huiyu, Yang Haiyang, Ou Ying, Zhang Quanyuan, Cheng Fan, Hu Fuqiang, Liu Hai, Xu Zushun, Gong Chunli
Hubei Engineering & Technology Research Center for Functional Materials from Biomass, School of Chemistry and Material Science, Hubei Engineering University, Xiaogan, Hubei 432000, China.
Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Key Laboratory of Polymer Materials, School of Materials Science and Engineering, Hubei University, Wuhan 430062, China.
ACS Appl Mater Interfaces. 2024 Jan 17;16(2):2751-2762. doi: 10.1021/acsami.3c15643. Epub 2024 Jan 5.
Anion exchange membranes (AEMs) are increasingly becoming a popular research area due to their ability to function with nonprecious metals in electrochemical devices. Nevertheless, there is a challenge to simultaneously optimize the dimensional stability and ionic conductivity of AEMs due to the "trade-off" effect. Herein, we adopted a novel strategy of combining filling and cross-linking using functionalized bacterial cellulose (PBC) as a dual-functional porous support and brominated poly(phenylene oxide) (Br-PPO) as the cross-linking agent and filler. The PBC nanofiber framework together with cross-linking can provide a reliable mechanical support for the subsequent filled polymer, thus improving the mechanical properties and effectively limiting the size change of the final quaternized-PPO (QPPO)-filled PBC composite membrane. The composite membrane showed a very low swelling ratio of only 10.35%, even at a high water uptake (81.83% at 20 °C). Moreover, the existence of multiple -NR groups in the cross-link bonds between BC and Br-PPO can provide extra OH- ion transport sites, contributing to the increase in ionic conductivity. The final membrane demonstrated a hydroxide ion conductivity of 62.58 mS cm, which was remarkably higher than that of the pure QPPO membrane by up to 235.93% (80 °C). The successful preparation of the PBC/QPPO membrane provides an effective avenue to tackle the trade-off effect through a dual-functional strategy.
阴离子交换膜（AEMs）因其在电化学装置中能够与非贵金属一起发挥作用，正日益成为一个热门的研究领域。然而，由于“权衡”效应，要同时优化AEMs的尺寸稳定性和离子电导率存在挑战。在此，我们采用了一种新颖的策略，即将填充和交联相结合，使用功能化细菌纤维素（PBC）作为双功能多孔支撑体，溴化聚亚苯基氧化物（Br-PPO）作为交联剂和填充剂。PBC纳米纤维框架与交联作用一起，可以为后续填充的聚合物提供可靠的机械支撑，从而改善机械性能并有效限制最终季铵化-PPO（QPPO）填充PBC复合膜的尺寸变化。该复合膜即使在高吸水率（20℃时为81.83%）下，也显示出仅10.35%的极低溶胀率。此外，BC和Br-PPO之间的交联键中多个-NR基团的存在可以提供额外的OH-离子传输位点，有助于提高离子电导率。最终的膜表现出62.58 mS cm的氢氧根离子电导率，在80℃时比纯QPPO膜显著高出235.93%）。PBC/QPPO膜的成功制备通过双功能策略为解决权衡效应提供了一条有效途径。
