TY - JOUR

T1 - Structural Transitions of the Metal-Organic Framework DUT-49(Cu) upon Physi- and Chemisorption Studied by in Situ Electron Paramagnetic Resonance Spectroscopy

AU - Polyukhov, Daniil M.

AU - Krause, Simon

AU - Bon, Volodymyr

AU - Poryvaev, Artem S.

AU - Kaskel, Stefan

AU - Fedin, Matvey V.

N1 - Funding Information: This work was supported by RFBR (18-29-04013). A.S.P. thanks the Ministry of Science and Higher Education (MSHE) of the Russian Federation (Grant 14.W03.31.0034). We thank MSHE for access to the EPR equipment. Publisher Copyright: Copyright © 2020 American Chemical Society. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/8/6

Y1 - 2020/8/6

N2 - Flexible metal-organic frameworks (MOFs) exhibit a variety of phenomena attractive for basic and applied science. DUT-49(Cu) is one of the remarkable representatives of such MOFs, where phase transitions are coupled to pressure amplification and "negative gas adsorption". In this work we report important insights into structural transitions of DUT-49(Cu) upon physi- and chemisorption of gases and volatile liquids obtained by in situ electron paramagnetic resonance (EPR) spectroscopy. In this method, phase transitions are detected via the zero-field splitting in dimeric copper(II) units. First, a new approach was validated upon physisorption of n-butane. Then, using diethyl ether, we for the first time demonstrated that chemisorption can also trigger phase transition in DUT-49(Cu). On the basis of the EPR results, the transition appears completely reversible. The developed EPR-based approach can also be extended to other flexible MOFs containing paramagnetic metal paddlewheels, where high sensitivity and spectral resolution allow in situ studies of stimuli-induced structural variability.

AB - Flexible metal-organic frameworks (MOFs) exhibit a variety of phenomena attractive for basic and applied science. DUT-49(Cu) is one of the remarkable representatives of such MOFs, where phase transitions are coupled to pressure amplification and "negative gas adsorption". In this work we report important insights into structural transitions of DUT-49(Cu) upon physi- and chemisorption of gases and volatile liquids obtained by in situ electron paramagnetic resonance (EPR) spectroscopy. In this method, phase transitions are detected via the zero-field splitting in dimeric copper(II) units. First, a new approach was validated upon physisorption of n-butane. Then, using diethyl ether, we for the first time demonstrated that chemisorption can also trigger phase transition in DUT-49(Cu). On the basis of the EPR results, the transition appears completely reversible. The developed EPR-based approach can also be extended to other flexible MOFs containing paramagnetic metal paddlewheels, where high sensitivity and spectral resolution allow in situ studies of stimuli-induced structural variability.

UR - http://www.scopus.com/inward/record.url?scp=85089611758&partnerID=8YFLogxK

U2 - 10.1021/acs.jpclett.0c01705

DO - 10.1021/acs.jpclett.0c01705

M3 - Article

C2 - 32615766

AN - SCOPUS:85089611758

VL - 11

SP - 5856

EP - 5862

JO - Journal of Physical Chemistry Letters

JF - Journal of Physical Chemistry Letters

SN - 1948-7185

IS - 15

ER -