Synthesis and characterization of three amino-functionalized metal–organic frameworks based on the 2-aminoterephthalic ligand

Abstract

The incorporation of Lewis base sites and open metal cation sites into metal-organic frameworks (MOFs) is a potential route to improve selective CO 2 adsorption from gas mixtures. In this study, three novel amino-functionalized metal-organic frameworks ( solvothermal reactions of 2-aminoterephthalic acid (H 2 ABDC) with magnesium, cobalt and strontium metal centers, respectively. Single-crystal structure analysis showed that Mg-ABDC and Co-ABDC were isostructural compounds comprising two-dimensional layered structures. The Sr-ABDC contained a three-dimensional motif isostructural to its known Ca analogue. The amino-functionalized MOFs were characterized by powder X-ray diffraction, thermal gravimetric analysis and N 2 sorption. The CO 2 and N 2 equilibrium adsorption capacities were measured at different temperatures (0 and 25°C). The CO 2 /N 2 selectivities of the MOFs were 396 on Mg-ABDC, 326 on Co-ABDC and 18 on Sr-ABDC. Both Mg-ABDC and Co-ABDC exhibit high heat of CO 2 adsorption (>30 kJ mol −1 ). The Sr-ABDC displays good thermal stability but had a low adsorption capacity resulting from narrow pore apertures.

Calcium and Strontium Coordination Polymers Based on Rigid and Flexible Aromatic Dicarboxylates: Synthesis, Structure, Photoluminescence and Dielectric Properties

“…Solids 2 and 4 are isostructural and hence, only the crystal structure of 4 is reported here. Crystal structure of the solids 2 and 4 were similar to those reported by Liang et al and Zhu et al.…”

“…In all the cases, the emission bands of the compounds are dominantly from the free ligands, suggesting that the metal‐to‐ligand charge transfer (MLCT) or ligand‐to‐metal charge transfer (LMCT) are less pronounced in these solids. Thus, the emission from these solids are from a combined effect of intra‐ligand and ligand‐to‐ligand charge transition (LLCT), as reported for other similar coordination polymers ,. Photoluminescence excitation (PLE) and the emission spectra at different excitation wavelengths for both ligands and solids are given in supplementary information (Figure S12, 13 and 14).…”

Supramolecular cyclodextrin-based metal-organic frameworks as efficient carrier for anti-inflammatory drugs

“…Also, drug delivery systems need to be biocompatible; however, the vast majority of recently developed MOFs were non-renewable, which the metal nodes and organic linkers used were toxic, making these materials unsuitable for biomedical applications [10]. Thus, the development of MOFs using biologically acceptable metals, such as Ca, Fe, Zn, K, Na and Ti, and natural linkers such as peptides [8], carbohydrates [11] and amino acids [12] has recently increased.…”

Review of Recent Developments in CO2 Capture Using Solid Materials: Metal Organic Frameworks (MOFs)

“…and Sr, respectively) and a relatively low CO 2 uptake (1.4 mmol/g at 1 bar and 298 K), the prepared MOFs had exceptional selectivity toward CO 2 (396 was recorded for Mg-ABDC) and exhibited high heat of adsorption [148]. Shimizu and coworkers [149] used 3-amino-1,2,4triazole ligands to design a 3D structure MOF with 782 m 2 /g surface area and 0.19 cm 3 /g pore volume that is capable to achieve CO 2 uptake of 4.35 mmol/g at 1.2 bar and 273 K. Moreover, the as-synthesized MOF has shown enthalpy of adsorption of 40.8 kJ/mol at zero coverage which was comparable to the commercial zeolite NaX (48.2 kJ/mol).…”