Chen Yalan, Fang Mingwei, Ding Shaosong, Liu You, Wang Xingpu, Guo Yumeng, Sun Xiang, Zhu Ying
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology Ministry of Education, School of Chemistry, Beihang University, Beijing 100191, China.
Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China.
ACS Appl Mater Interfaces. 2022 May 11. doi: 10.1021/acsami.2c04307.
The waste organic solvents containing inorganic salts have been considered sustainable resources, which can effectively capture salinity gradient energy using ion-selective membranes. However, it still remains a great challenge to fabricate the ion-selective membranes with high conversion efficiency and stability in an organic system. Here, the bioinspired nacre-like layered MXene/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) (MP) composite membranes for capturing salinity gradient energy from an organic solvent are fabricated via filtration method, in which PEDOT:PSS molecules are introduced into MXene interlayers. Accordingly, the MP membrane exhibits high mechanical property and wonderful stability in common organic solvents. As expected, the power generation of the MP membrane reaches up to 3216 ± 603 nW in a 2/0.001 M methanol (Met)-LiCl solution and a record high power generation of 6926 ± 959 nW after adding NaOH into the Met-LiCl solution, which is superior to the previous report. Both experimental and theoretical studies confirm that the MP membrane has excellent cation selectivity and fast ion transport performance. The results are attributable to an increased interlayer spacing between MXene layers and an improved cation selectivity due to the insertion of PEDOT:PSS chains and the enhanced dissociation of negative charges by NaOH. The ultrastable two-dimensional (2D) nanochannel membrane provides practical application for harvesting energy from waste organic solvents.
含有无机盐的废弃有机溶剂被视为可持续资源，其可利用离子选择性膜有效捕获盐度梯度能。然而，在有机体系中制备具有高转换效率和稳定性的离子选择性膜仍然是一个巨大的挑战。在此，通过过滤法制备了受生物启发的类珍珠母层状MXene/聚（3,4-乙撑二氧噻吩）-聚（苯乙烯磺酸盐）（PEDOT:PSS）（MP）复合膜，用于从有机溶剂中捕获盐度梯度能，其中PEDOT:PSS分子被引入MXene层间。相应地，MP膜在常见有机溶剂中表现出高机械性能和出色的稳定性。正如预期的那样，MP膜在2/0.001 M甲醇（Met）-LiCl溶液中的发电量高达3216±603 nW，在向Met-LiCl溶液中加入NaOH后，发电量达到创纪录的6926±959 nW，优于先前的报道。实验和理论研究均证实，MP膜具有优异的阳离子选择性和快速的离子传输性能。这些结果归因于MXene层间间距的增加以及由于PEDOT:PSS链的插入导致的阳离子选择性提高，以及NaOH对负电荷解离的增强。这种超稳定的二维（2D）纳米通道膜为从废弃有机溶剂中收集能量提供了实际应用。
