Effects of varying water adsorption on a Cu3(BTC)2 metal–organic framework (MOF) as studied by 1H and 13C solid-state NMR spectroscopy

Abstract

The process of water adsorption on a dehydrated Cu(3)(BTC)(2) (copper (II) benzene 1,3,5-tricarboxylate) metal-organic framework (MOF) was studied with (1)H and (13)C solid-state NMR. Different relative amounts of water (0.5, 0.75, 1, 1.5, 2, and 5 mole equivalents with respect to copper) were adsorbed via the gas phase. (1)H and (13)C MAS NMR spectra of dehydrated and water-loaded Cu(3)(BTC)(2) samples gave evidence on the structural changes due to water adsorption within the MOF material as well as information on water dynamics. The analysis of (1)H spinning sideband intensities reveals differences in the (1)H-(63/65)Cu hyperfine coupling between dehydrated and water-loaded samples. The investigation was continued for 60 days to follow the stability of the Cu(3)(BTC)(2) network under humid conditions. NMR data reveal that Cu(3)(BTC)(2) decomposes quite fast with the decomposition being different for different water contents.

Tuning the nitric oxide release behavior of amino functionalized HKUST-1

“…Additionally, the intensity of the alkyl proton signal is increasing with respect to the aromatic proton signal due to the higher number of protons with increasing alkyl chain length. The large line width, which is due to interaction with the unpaired electron at the copper site [39] prevents resolution of all signals for the individual functional groups. By signal deconvolution of the full spectrum including spinning sidebands, quantification of the final incorporation of the two linkers inside the MOFs was possible.…”

Mapping the Cu-BTC metal–organic framework (HKUST-1) stability envelope in the presence of water vapour for CO2 adsorption from flue gases

“…Sensitivity to water vapour is widely considered to be a major weakness of MOFs as adsorption materials that could destroy their potential advantages from an application perspective [27]. HKUST-1 is hydrophilic and both theoretical [28][29][30] and experimental [31] investigations have shown the strong affinity of water molecules to copper centres in the HKUST-1 framework. Therefore, understanding the moisture stability of MOFs under the appropriate conditions for the CO 2 capture from flue gases (50-75°C and 0-1 barG) is necessary.…”

Synthesis, Crystal Structure, and Solid-State NMR Investigations of Heteronuclear Zn/Co Coordination Networks — A Comparative Study

“…Solid-state NMR is a versatile tool for studying the different interactions present in porous co-ordination frameworks, which is increasingly used for the characterization of structure and dynamics in these materials. [20][21][22][23][24] NMR spectra of solid samples provide information on the detailed local electronic structure of each nucleus reflected as chemical shift without the need of long-range order. Therefore, non-crystalline materials can be characterized with solid-state NMR which is increasingly used for the characterization of structure and dynamics in these materials.…”