Abstract
The sol-gel synthesis represents a versatile platform to fabricate ceramic inorganic membranes. However, it is still a grand challenge to push the boundary of sol-gel chemistry towards high-quality organic membrane construction. Herein, a facile and controlled nanocrystal suturing strategy in sol-gel solutions is developed to afford highly crystalline and free-standing covalent organic framework membranes. The key chemistry design lies in deploying tiny threads (1 mol% dual-NH2-tail linear polymer) to efficiently suture the highly charged covalent organic framework nanocrystals stabilized and confined in sol-gel solutions, creating a continuous and intact membrane surface. A subsequent treatment heals the sutured covalent organic framework nanocrystals, yielding a free-standing membrane with high crystallinity and ordered pores. The structure evolution and role of the thread linker are elucidated via operando spectroscopy and microscopy. The as-afforded covalent organic framework membranes demonstrate attractive proton transport performance in high temperature and anhydrous fuel cell applications.
| Original language | English |
|---|---|
| Article number | 5712 |
| Journal | Nature Communications |
| Volume | 16 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2025 |
Funding
The research was supported financially by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences, US Department of Energy. The DLS experiments were performed at the Center for Nanophase Materials Sciences (CNMS), which is a US Department of Energy, Office of Science User Facility at Oak Ridge National Laboratory. SAXS measurements were enabled by the Major Research Instrumentation program of the National Science Foundation under Award No. DMR-1827474 (E.L.). AFM measurements were performed on a Park NX20-AFM of the Center for Functional Nanomaterials (CFN), which is a U.S. Department of Energy Office of Science User Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704 (X.T.).