Water vapour and gas induced phase transformations in an 8-fold interpenetrated diamondoid metal–organic framework

DOI: 10.1039/D3TA01574B

Authors: Aizhamal Subanbekova (University of Limerick) , Varvara I. Nikolayenko (University of Limerick) , Andrey A. Bezrukov (University of Limerick) , Debobroto Sensharma (University of Limerick) , Naveen Kumar (University of Limerick) , Daniel J. O'Hearn (University of Limerick) , Volodymyr Bon (Technische Universität Dresden) , Shi-Qiang Wang (University of Limerick; Agency for Science, Technology and Research (A*STAR)) , Kyriaki Koupepidou (University of Limerick) , Shaza Darwish (University of Limerick) , Stefan Kaskel (Technische Universität Dresden) , Michael J. Zaworotko (University of Limerick)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Materials Chemistry A , VOL 11 , PAGES 9691 - 9699

State: Published (Approved)
Published: May 2023
Diamond Proposal Number(s): 30456

Abstract: In this work, we report the synthesis, structural characterisation and sorption properties of an 8-fold interpenetrated diamondoid (dia) metal–organic framework (MOF) that is sustained by a new extended linker ligand, [Cd(Imibz)2], X-dia-2-Cd, HImibz or 2 = 4-((4-(1H-imidazol-1-yl)phenylimino)methyl)benzoic acid. X-dia-2-Cd was found to exhibit reversible single-crystal-to-single-crystal (SC–SC) transformations between four distinct phases: an as-synthesised (from N,N-dimethylformamide) wide-pore phase, X-dia-2-Cd-α; a narrow-pore phase, X-dia-2-Cd-β, formed upon exposure to water; a narrow-pore phase obtained by activation, X-dia-2-Cd-γ; a medium-pore CO2-loaded phase X-dia-2-Cd-δ. While the space group remained constant in the four phases, the cell volumes and calculated void space ranged from 4988.7 Å3 and 47% (X-dia-2-Cd-α), respectively, to 3200.8 Å3 and 9.1% (X-dia-2-Cd-γ), respectively. X-dia-2-Cd-γ also exhibited a water vapour-induced structural transformation to the water-loaded X-dia-2-Cd-β phase, resulting in an S-shaped sorption isotherm. The inflection point occurred at 18% RH with negligible hysteresis on the desorption profile. Water vapour temperature-humidity swing cycling (60% RH, 300 K to 0% RH, 333 K) indicated hydrolytic stability of X-dia-2-Cd and working capacity was retained after 128 cycles of sorbent regeneration. CO2 (at 195 K) was also observed to induce a structural transformation in X-dia-2-Cd-γ and in situ PXRD studies at 1 bar of CO2, 195 K revealed the formation of X-dia-2-Cd-δ, which exhibited 31% larger unit cell volume than X-dia-2-Cd-γ.

Diamond Keywords: Gas Separation

Subject Areas: Materials, Chemistry


Instruments: I11-High Resolution Powder Diffraction

Added On: 03/05/2023 08:35

Documents:
d3ta01574b.pdf

Discipline Tags:

Chemistry Materials Science Chemical Engineering Engineering & Technology Metal-Organic Frameworks Metallurgy Organometallic Chemistry

Technical Tags:

Diffraction X-ray Powder Diffraction