Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 21, 2020
Previous Article Next Article

Impact of dehydration and mechanical amorphization on the magnetic properties of Ni(ii)-MOF-74

Author affiliations

Abstract

Mechanically responsive metal–organic frameworks (MOFs) came very recently into the spotlight of material science for their unique properties and potential new fields of application. We present here a clarification of the magnetic properties of prototypical magnetic MOF-74 material, Ni(II)-MOF-74, using magnetization measurements, X-band electron spin resonance (ESR), multi-frequency high-field ESR (HF-ESR), and theoretical model. It was established that the guests populating the honeycomb channels have little influence on the magnetism of Ni-MOF-74, whereas magnetic properties change significantly upon mechanical amorphization. Amorphous material (am-Ni-MOF-74), which can be readily prepared by the mechanochemical treatment of dehydrated Ni-MOF-74 (deh-Ni-MOF-74), as shown by in situ monitoring methods, displays significantly lower bulk magnetization compared to Ni-MOF-74 and deh-Ni-MOF-74. This decline in magnetization is established to be a consequence of the spin-crossover from high-spin to a low-spin state of nickel(II) ions. The observed spin-crossover was rationalized by an insight into the changes of the nickel coordination sphere during the amorphization, which was provided by solid-state nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. Additionally, it was found that am-Ni-MOF-74 behaves differently than its zinc analogue when exposed to vapors or liquid-additives in the milling process, indicating that the nature of the metal node plays a substantial role in the mechanical properties of this modular family of MOF materials.

Graphical abstract: Impact of dehydration and mechanical amorphization on the magnetic properties of Ni(ii)-MOF-74

Back to tab navigation

Supplementary files

Article information


Submitted
18 Feb 2020
Accepted
20 Apr 2020
First published
20 Apr 2020

J. Mater. Chem. C, 2020,8, 7132-7142
Article type
Paper

Impact of dehydration and mechanical amorphization on the magnetic properties of Ni(II)-MOF-74

S. Muratović, B. Karadeniz, T. Stolar, S. Lukin, I. Halasz, M. Herak, G. Mali, Y. Krupskaya, V. Kataev, D. Žilić and K. Užarević, J. Mater. Chem. C, 2020, 8, 7132
DOI: 10.1039/D0TC00844C

Social activity

Search articles by author

Spotlight

Advertisements