Imaging defects and their evolution in a metal–organic framework at sub-unit-cell resolution

Liu, Lingmei; Chen, Zhijie; Wang, Jianjian; Zhang, Daliang; Zhu, Yihan; Ling, Sanliang; Huang, Kuo Wei; Belmabkhout, Youssef; Adil, Karim; Zhang, Yuxin; Slater, Ben; Eddaoudi, Mohamed; Han, Yu

Abstract

© 2019, The Author(s), under exclusive licence to Springer Nature Limited. Defect engineering of metal–organic frameworks (MOFs) offers promising opportunities for tailoring their properties to specific functions and applications. However, determining the structures of defects in MOFs—either point defects or extended ones—has proved challenging owing to the difficulty of directly probing local structures in these typically fragile crystals. Here we report the real-space observation, with sub-unit-cell resolution, of structural defects in the catalytic MOF UiO-66 using a combination of low-dose transmission electron microscopy and electron crystallography. Ordered ‘missing linker’ and ‘missing cluster’ defects were found to coexist. The missing-linker defects, reconstructed three-dimensionally with high precision, were attributed to terminating formate groups. The crystallization of the MOF was found to undergo an Ostwald ripening process, during which the defects also evolve: on prolonged crystallization, only the missing-linker defects remained. These observations were rationalized through density functional theory calculations. Finally, the missing-cluster defects were shown to be more catalytically active than their missing-linker counterparts for the isomerization of glucose to fructose.

Citation

Liu, L., Chen, Z., Wang, J., Zhang, D., Zhu, Y., Ling, S., …Han, Y. (2019). Imaging defects and their evolution in a metal–organic framework at sub-unit-cell resolution. Nature Chemistry, 11(7), 622-628. https://doi.org/10.1038/s41557-019-0263-4

• Journal Article Type: Article
• Acceptance Date: Mar 26, 2019
• Online Publication Date: May 13, 2019
• Publication Date: 2019-07
• Deposit Date: Jul 31, 2019
• Publicly Available Date: Nov 14, 2019
• Journal: Nature Chemistry
• Print ISSN: 1755-4330
• Electronic ISSN: 1755-4349
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 7
• Pages: 622-628
• DOI: https://doi.org/10.1038/s41557-019-0263-4
• Keywords: General Chemistry; General Chemical Engineering
• Public URL: https://nottingham-repository.worktribe.com/output/2360943
• Publisher URL: https://www.nature.com/articles/s41557-019-0263-4
• Additional Information: Received: 4 July 2018; Accepted: 26 March 2019; First Online: 13 May 2019; : The authors declare no competing interests.