A Series of Metal–Organic Frameworks: Syntheses, Structures and Luminescent Detection, Gas Adsorption, Magnetic Properties

Abstract

Six metal–organic frameworks of [Cd2­(L)2­(mmpa)2]·6H2O (1), [Mn2(L)2(mmpa)2]·L·2H2O (2), [Zn­(L)­(NO2 mbda)]·H2O (3), [Cu­(L)­(NO2 mbda)] (4), [Co3­(L)2­(BTC)2­(H2O)4]·H2O (5), and [Co3­(L)2­(OBTC)2­(H2O)2] (6) were prepared based on different metal salts and the mixed ligands including the N-heterocyclic 1-(4-(1H-imidazol-5-yl)­phenyl)-1H-1,2,4-triazole (L) ligand and auxiliary carboxylic acids of 5-methylisophthalic acid (H2 mmpa), 5-nitroisophthalic acid (H2NO2 mbda), trimesuc acid (H3BTC), and 1,2,3-benzenetricarboxylic acid (H3OBTC). MOFs 1 and 2 are isomorphous and isostructural, and both are binodal 4-connected CdS network based on Cd2(COO)2 binuclear secondary building unit (SBU). Compound 3 is a 2D → 3D “polycatenated network” because of its mutual interpenetration between two-dimensional (2D) corrugated (4, 4) layers, while 4 is a sql network on the basis of binuclear [Cu2(COO)2] SBUs. Compound 5 is a trinodal (3, 4)-connected rare nor-3,4-C2/m 3-fold interpenetrated net, while 6 is a 4-connected 3D frl/Ferey ladder net based on L and two isomers of benzenetricarboxylic acids. Photoluminescent properties were determined for the corresponding d10 MOFs. Microporous crystalline material 1 can selectively sense nitroaromatic compounds by fluorescence quenching and show a rare luminescent sensing property for Ag+ ions in H2O solution. Also, the activated microporous material 1 can selectively adsorb CO2 over N2 and undergo H2O vapor adsorption. Furthermore, magnetostructural analyses have also shown that MOFs 2, 4, 5, and 6 consisting of the paramagnetic ions Mn­(II), Cu­(II)/Co­(II), and carboxylate or N-heterocyclic organic molecules exhibit meaningful magnetic-exchange coupling properties.

The Structure and Property of Two Different Metal-Organic Frameworks Based on N/O-Donor Mixed Ligands

“…As the single 3D framework has 1D square channels with a pore diameter approximately 5.8 Å, it allows other two similar framework to interpenetrate in the channels, and as a result, the 3D networks of 2 interlock each other, forming a 3-fold interpenetration networks (Figure 7). It should be mentioned that both of the MOF 2 and the reported structure of [Co 3 (L) 2 (BTC) 2 (H 2 O) 4 ]•H 2 O crystallize in the same monoclinic C2/c space group with similar cell parameters (Table 1), they are isomorphous and isostructural as confirmed by X-ray crystallographic analysis [21]…”

“…Recently, Chen group have designed the multi-N donor ligand 1-(4-(1H-imidazol-5-yl)phenyl)-1H-1,2,4-triazole, which potentially have diverse coordination modes due to the favorable multi-N coordination ability with metal atoms. Moreover, considering their good compatibility for the mixed multi-N and carboxylic acid ligands, the group have synthesized a series of various MOFs with good properties [21]. As…”

“…Certainly, the different composition can affect the resulting structures. The reported MOF of [Co 3 (L) 2 (OBTC) 2 (H 2 O) 2 ] built from AZN and the isomer H 3 OBTC of H 3 btc[21], the quite different coordination modes of OBTC 3− make distinct structures for these two Co-based compounds.…”

A Cu2I2-Based Coordination Framework as the Selective Sensor for Ag+ and the Effective Adsorbent for I2

“…has resulted in the discharge of massive pollutants such as heavy metal ions into the natural environment, which brings a significant threat to human beings and living bodies. − For instance, the existence of Ag + in water may cause irreversible argyria and even lead to the liver injury, kidney damage, and epilepsy when an excessive silver ingestion occurs in humans. − Therefore, it is highly essential to design a facile and effective method for the fast recognition of targeted species. At present, though several detecting means, such as atomic absorption spectrometry, gas chromatography, and ion mobility spectrometry, have been developed, they suffer from inconvenience and a high-cost nature. , By contrast, luminescent chemosensors have been in high demand for contaminant monitoring recently, owing to their inexpensiveness, high accuracy, quick response, and excellent selectivity. − Consequently, pursuit of original and appropriate luminous materials for the specific metal sensing is of great importance and high urgency. On the other hand, developing nuclear industry brings about the emission of radioactive iodine, further causing a series of environment issues. − Apart from some strategies during iodine removal processes such as ion-exchange resin, extraction, and sodium filtration, the sorption method featuring ecofriendliness and high efficiency is regarded as a more competitive one.…”

Syntheses, crystal structures, and fluorescent properties of three coordination polymers with 5-sulfoisophthalic acid anion and 4-phenylpyridine

“…[1][2][3][4][5][6] It is well-known that many factors such as synthetic methods, central metals, ligands, and pH can influence the final structures of CPs. [7][8][9][10] There is no doubt that organic ligands and the metal center play a significant role in the design and synthesis of CPs, while selecting the coordination geometry of the metal centers and organic ligands containing appropriate functional groups (such as polycarboxylic acid or multipyridine ligands) are also key for constructing CPs. Due to the high coordination numbers and flexible coordination geometries of transition-metal ions, they are able to produce a variety of structures.…”