Establishing Covalent Organic Framework "A&B" Gel via Hydrogen Bond Exchange-Induced Microphase Separation

Rapid and controllable gelation of covalent organic framework (COF) materials with ordered accessible nanochannels is conducive to their use in versatile applications. However, challenges arise from intricate high-rate polymerization processes and unregulated phase separation, which complicate the fine management on equilibrium morphology and crystallinity in COFs. Herein, inspired by prevalent hydrogen bonding interactions in nature, a hydrogen bond exchange (HBE)-induced microphase separation (termed HBEiMS) pathway is proposed for the facile preparation of hydrazone-linked COF "A&B" gels. The split-prepared Glue A and Glue B avoid aggregation formation and precipitation of the powdered products after non-homogeneous phase nucleation following the rapid reaction of monomers in a one-pot manner. The phase transformation induced by HBE enables homogeneous separation of bulk materials, resulting in successful preparation of highly crystalline COF gels in seconds at room temperature. Furthermore, the charge transport of oxygen atoms within the robust COF pores is better controlled by modifying the distal group of the monomer side chains, resulting in a high cycling stability of the gel electrolyte beyond 1600 h. Collectively, findings in this study can fuel future development of COF materials and their possible commercial use.