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Nature

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Reconstructed covalent organic frameworks

Published:6 April 2022 DOI: 10.1038/s41586-022-04443-4
Weiwei Zhang, Linjiang Chen, Sheng Dai, Chengxi Zhao, Cheng Ma, Lei Wei, Minghui Zhu, Samantha Y. Chong, Haofan Yang, Lunjie Liu, Yang Bai, Miaojie Yu, Yongjie Xu, Xiao-Wei Zhu, Qiang Zhu, Shuhao An, Reiner Sebastian Sprick, Marc A. Little, Xiaofeng Wu, Shan Jiang, Yongzhen Wu, Yue-Biao Zhang, He Tian, Wei-Hong Zhu, Andrew I. Cooper

Abstract

Covalent organic frameworks (COFs) are distinguished from other organic polymers by their crystallinity1–3, but it remains challenging to obtain robust, highly crystalline COFs because the framework-forming reactions are poorly reversible4,5. More reversible chemistry can improve crystallinity6–9, but this typically yields COFs with poor physicochemical stability and limited application scope5. Here we report a general and scalable protocol to prepare robust, highly crystalline imine COFs, based on an unexpected framework reconstruction. In contrast to standard approaches in which monomers are initially randomly aligned, our method involves the pre-organization of monomers using a reversible and removable covalent tether, followed by confined polymerization. This reconstruction route produces reconstructed COFs with greatly enhanced crystallinity and much higher porosity by means of a simple vacuum-free synthetic procedure. The increased crystallinity in the reconstructed COFs improves charge carrier transport, leading to sacrificial photocatalytic hydrogen evolution rates of up to 27.98?mmol?h?1?g?1. This nanoconfinement-assisted reconstruction strategy is a step towards programming function in organic materials through atomistic structural control. A protocol in which monomers are pre-organized using a reversible and removable urea linkage enables the production of covalent organic frameworks with higher crystallinity and porosity than those produced using standard approaches with randomly aligned monomers.

Substances (2)

Materials
Procduct Name CAS Molecular Formula Supplier Price
2,4,6-Triformylphloroglucinol 34374-88-4 C9H6O6 149 suppliers $105.00-$743.00
2,4,6-Triformylphloroglucinol 34374-88-4 C9H6O6 149 suppliers $105.00-$743.00

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