3D covalent organic framework membrane with fast and selective ion transport

• Published in: Nature communications Vol. 14; no. 1; p. 5926
• Main Authors: Zhu, Tianhao, Kong, Yan, Lyu, Bohui, Cao, Li, Shi, Benbing, Wang, Xiaoyao, Pang, Xiao, Fan, Chunyang, Yang, Chao, Wu, Hong, Jiang, Zhongyi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 22.09.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/131; 147/135; 147/143; 147/3; 639/301/299/1013; 639/301/357/537; 639/638/298/923/1028; Acids; Conductivity; Covalence; Energy conversion; Energy conversion efficiency; Fabrication; Humanities and Social Sciences; Ion exchange; Ion transport; Ions; Membranes; multidisciplinary; Polymerization; Science; Science (multidisciplinary); Selectivity; Sulfonic acid; Tradeoffs
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-41555-5

3D ionic covalent organic framework (COF) membranes, which are envisioned to be able to break the trade-off between ion conductivity and ion selectivity, are waiting for exploitation. Herein, we report the fabrication of a 3D sulfonic acid-functionalized COF membrane (3D SCOF) for efficient and selective ion transport, using dual acid-mediated interfacial polymerization strategy. The 3D SCOF membranes possess highly interconnected ion transport channels, ultramicroporous pore sizes (0.97 nm), and abundant sulfonate groups (with a high ion exchange capacity of 4.1 mmol g −1 ), leading to high proton conductivity of 843 mS cm −1 at 90 °C. When utilized in osmotic energy conversion, a high power density of 21.2 W m −2 , and a remarkable selectivity of 0.976 and thus an exceptional energy conversion efficiency of 45.3% are simultaneously achieved. This work provides an alternative approach to 3D ionic COF membranes and promotes the applications of 3D COFs in ion transport and separation. 3D ionic covalent organic frameworks (iCOF) are used in the fabrication of membranes breaking the trade-off between ion conductivity and ion selectivity is challenging. Here, the authors report the fabrication of a 3D sulfonic acid-functionalized iCOF membrane for efficient and selective ion transport, using dual acid-mediated interfacial polymerization