Magnetic control of MOF crystal orientation and alignment

Cheng, Fei; Marshall, Ellis S.; Young, Adam J.; Robinson, Peter J.; Bouillard, Jean Sebastien G.; Adawi, Ali M.; Vermeulen, Nicolaas A.; Farha, Omar K.; Reithofer, Michael R.; Chin, Jia Min

Abstract

Most metal-organic frameworks (MOFs) possess anisotropic properties, the full exploitation of which necessitates a general strategy for the controllable orientation of such MOF crystals. Current methods largely rely upon layer-by-layer MOF epitaxy or tuning of MOF crystal growth on appropriate substrates, yielding MOFs with fixed crystal orientations. Here, the dynamic magnetic alignment of different MOF crystals (NH2-MIL-53(Al) and NU-1000) is shown. The MOFs were magnetized by electrostatic adsorption of iron oxide nanoparticles, dispersed in curable polymer resins (Formlabs 1+ clear resin/ Sylgard 184), magnetically oriented, and fixed by resin curing. The importance of crystal orientation on MOF functionality was demonstrated whereby magnetically aligned NU-1000/Sylgard 184 composite was excited with linearly polarized 405 nm light, affording an anisotropic fluorescence response dependent on the polarization angle of the excitation beam relative to NU-1000 crystal orientation.

Citation

Cheng, F., Marshall, E. S., Young, A. J., Robinson, P. J., Bouillard, J. S. G., Adawi, A. M., …Chin, J. M. (2017). Magnetic control of MOF crystal orientation and alignment. Chemistry: a European journal, 23(62), 15578-15582. https://doi.org/10.1002/chem.201703812

• Journal Article Type: Article
• Acceptance Date: Sep 14, 2017
• Online Publication Date: Oct 4, 2017
• Publication Date: Nov 7, 2017
• Deposit Date: Oct 4, 2017
• Publicly Available Date: Oct 4, 2017
• Journal: Chemistry - A European journal
• Print ISSN: 0947-6539
• Electronic ISSN: 1521-3765
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 23
• Issue: 62
• Pages: 15578-15582
• DOI: https://doi.org/10.1002/chem.201703812
• Keywords: Anisotropy; Fluorescence; Magnetic alignment; Metal-organic framework; Polymer composites
• Public URL: https://hull-repository.worktribe.com/output/455423
• Publisher URL: http://onlinelibrary.wiley.com/doi/10.1002/chem.201703812/full
• Additional Information: This is a description of an article published in Chemistry - A European journal, 2017.