题 目: Controllable Synthesis and Ultrahigh Anisotropic Single-Crystal Proton Conduction
of a Hydrogen-Bonded Organic Framework
作 者: Wen-Wen Wu, Beibei Li, Meng-Meng Wang, Jun-Jie Cai, Swetha Andra, Hui-Jie Lun,* Yan Bai, Dong-Bin Dang,* and Ya-Min Li*
刊 名: Chem. Mater.
年卷页: 2023, 35, 6549-6556.
摘 要：Hydrogen-bonded organic frameworks (HOFs) with inherent well defined hydrogen-bond networks are promising proton conduction materials. Herein, four three-dimensional HOFs were controllably assembled from 1,2,4,5-benzenete tracarboxylic acid and guanidinium of different chain lengths with certain ratios, in which GC-1 has undergone a water-induced single-crystal-to-single-crystal (SCSC) transformation to a more stable GC-2 with successive π-π stacking interactions.
Notably, the ideal single-crystal sample of GC-2 exhibits an ultrahigh proton conductivity of 1.78 × 10−2 S cm−1 along the [100] direction at ambient temperature and 98% RH. This sample is highly anisotropic with 3-5 orders of magnitude higher than those along the [010] and [001] directions, which is closely related to favorable proton-transfer paths of 1D highly hydrophilic channels formed by the consecutive hydrogen-bonded network between protonated guanidinium cations and carboxylic acid anions along the a-axis direction. Compared with the pelletized samples of GC-2, GC-3, and GC-4, their composite membranes with Nafion show significant enhancement of proton conduction with remarkable values of 1.33 × 10−1, 1.92 × 10−1, and 1.98 × 10−1 S cm−1 at 338 K and 98% RH, indicating great application potential.
文章链接：https://doi.org/10.1021/acs.chemmater.3c01669
