Structural study of Ni- or Mg-based complexes incorporated within UiO-66-NH{sub 2} framework and their impact on hydrogen sorption properties
- Laboratory for Inorganic Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia)
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles Saint-Quentin-en-Yvelines, 78035 Versailles (France)
Nickel and magnesium acetylacetonate molecular complexes were post-synthetically incorporated into microporous zirconium-based MOF (UiO-66-NH{sub 2}) in order to introduce active open-metal sites for hydrogen sorption. Elemental analysis, nitrogen physisorption and DFT calculations revealed that 5 molecules of Ni(acac){sub 2} or 2 molecules of Mg(acac){sub 2} were incorporated into one unit cell of UiO-66-NH{sub 2}. {sup 1}H–{sup 13}C CPMAS and {sup 1}H MAS NMR spectroscopy showed that, although embedded within the pores, both Ni- and Mg-complexes interacted with the UiO-66-NH{sub 2} framework only through weak van der Waals bonds. Inclusion of metal complexes led to the decrease of hydrogen sorption capacities in Ni-modified as well as in Mg-modified samples in comparison with the parent UiO-66-NH{sub 2}. The isosteric hydrogen adsorption enthalpy slightly increased in the case of Ni-modified material, but not in the case of Mg-modified analogue. - Graphical abstract: A post-synthesis impregnation of Mg- and Ni-acetylacetonate complexes performed on zirconium-based MOF UiO-66-NH{sub 2} does influence the hydrogen sorption performance with respect to the parent matrix. The structural study revealed that Mg- and Ni-acetylacetonate molecules interact with zirconium-terephthalate framework only by weak interactions and they are not covalently bonded to aminoterephthalate ligand. Still, they remain confined into the pores even after hydrogen sorption experiments. - Highlights: • Mg- and Ni-acetylacetonate molecules embedded in the pores of UiO-66-NH{sub 2} by PSM. • Molecules of complexes interact with framework only by van der Waals interactions. • Type/structure of deposited metal-complex impact hydrogen enthalpy of adsorption.
- OSTI ID:
- 22475596
- Journal Information:
- Journal of Solid State Chemistry, Vol. 225; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
Efficient alkene epoxidation catalyzed by molybdenyl acetylacetonate supported on aminated UiO-66 metal−organic framework
Cu- and Zr-based metal organic frameworks and their composites with graphene oxide for capture of acid gases at ambient temperature
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ABSORPTION SPECTROSCOPY
ACETYLACETONE
ADSORPTION
CAPACITY
CARBON 13
COVALENCE
ENTHALPY
HYDROGEN 1
LIGANDS
MAGNESIUM COMPLEXES
MAGNESIUM COMPOUNDS
MOLECULES
NICKEL COMPOUNDS
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
SYNTHESIS
VAN DER WAALS FORCES
ZIRCONIUM COMPOUNDS