Modulating Skeletons of Covalent Organic Framework for High‐Efficiency Gold Recovery

Liu, Minghao; Jiang, Di; Fu, Yubin; Zheng Chen, George; Bi, Shuai; Ding, Xuesong; He, Jun; Han, Bao‐Hang; Xu, Qing; Zeng, Gaofeng

Abstract

Covalent organic frameworks (COFs) have attracted considerable attention as adsorbents for capturing and separating gold from electronic wastes. To enhance the binding capture efficiency, constructing hydrogen-bond nanotraps along the pore walls was one of the most widely adopted approaches. However, the development of absorbing skeletons was ignored due to the weak binding ability of the gold salts (Au). Herein, we demonstrated skeleton engineering to construct highly efficiently absorbs for Au capture. The strong electronic donating feature of diarylamine units enhanced the electronic density of binding sites (imine-linkage) and thus resulted in high capacities over 1750 mg g−1 for all three COFs. Moreover, the absorbing performance was further improved via the ionization of diarylamine units. The ionic COF achieved 90 % of the maximal adsorption capacity, 1.63 times of that from the charge-neutral COF within ten minutes, and showed remarkable uptakes of 1834 mg g−1, exceptional selectivity (97.45 %) and cycling stability. The theoretical calculation revealed the binding sites altering from imine bonds to ionic amine sites after ionization of the frameworks, which enabled to bind the AuCl4− via coulomb force and contributed to enhanced absorbing kinetics. This work inspires us to design molecular/ionic capture based on COFs.

Citation

Liu, M., Jiang, D., Fu, Y., Zheng Chen, G., Bi, S., Ding, X., He, J., Han, B., Xu, Q., & Zeng, G. (2024). Modulating Skeletons of Covalent Organic Framework for High‐Efficiency Gold Recovery. Angewandte Chemie International Edition, 63(1), Article e202317015. https://doi.org/10.1002/anie.202317015

• Journal Article Type: Article
• Acceptance Date: Nov 20, 2023
• Online Publication Date: Nov 20, 2023
• Publication Date: Jan 2, 2024
• Deposit Date: Nov 30, 2023
• Publicly Available Date: Nov 21, 2024
• Journal: Angewandte Chemie International Edition
• Print ISSN: 1433-7851
• Electronic ISSN: 1521-3773
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 63
• Issue: 1
• Article Number: e202317015
• DOI: https://doi.org/10.1002/anie.202317015
• Keywords: Skeleton Engineering, Binding Sites Conversion, Ionic Modification, Gold Ions Recovery, Covalent Organic Frameworks
• Public URL: https://nottingham-repository.worktribe.com/output/27867421
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1002/anie.202317015