Synthesis and characterization of zinc-organic frameworks with 1,4-benzenedicarboxylic acid and azobenzene-4,4′-dicarboxylic acid

Abstract

The solvothermal reactions of 1,4-bezenedicarboxylic acid (H 2 BDC) or azobenzene-4,4′-dicarboxylic acid (H 2 ABD) with zinc ions/clusters lead to the formation of four crystalline materials. All of these compounds were characterized by x-ray diffraction, optical microscopy, thermo-gravimetric analysis and nitrogen adsorption. Block-shaped crystals (BZ1) with various shapes and sizes were obtained at H 2 BDC:Zn mole ratio of 1:1 and H 2 BDC concentration of 0.1 M. At more dilute H 2 BDC concentration of 0.01 M and H 2 BDC:Zn mole ratio of 1 : 4, the reaction product was cubic crystals (BZ2) with a size of 250 μm. In the H 2 ABD system, flat-plate-like crystals (AZ1) were obtained at H 2 ABD:Zn mole ratio of 1 : 1 and H 2 ABD concentration of 0.01 M. Meanwhile, thick-block-like crystals (AZ2) were formed at the same H 2 ABD:Zn mole ratio but at 0.004 M H 2 ABD. The Langmuir surface area (S Lang ) of the materials was remarkable, enhanced by diluting the reaction solution. For the compounds synthesized in N , N′-dimethylformamide (DMF), S Lang increased from 304.6 m 2 g −1 for BZ1 to 2631 m 2 g −1 for BZ2 and from 475.8 m 2 g −1 for AZ1 to 3428 m 2 g −1 for AZ2. Meanwhile, BZ2 synthesized in N , N′-diethylformamide (BZ2/DEF) got the highest S Lang of 4330 m 2 g −1. Both AZ2 and BZ2 materials were stable up to 400 °C.

Functional Role of Metal Center and Doping on Tuning the Electrocatalytic Oxygen Evolution Activity of BioMIL-1: Experimental and Theoretical Approaches

“…12,13 The versatility of MOF composition by simply changing the metal ion (i.e., size, acidity, softness) and functional ligand (i.e., polarity, length, hydrophobicity) makes tuning their properties for OER possible. Various MOFs based on the 1,4 dicarboxylic acid benzene (1,4-BDC) linker, resulting in M-1,4-BDC, have been synthesized by changing the metal ion, such as Zn 2+ , 14 Cu 2+ , 15 Co 2+ , 16 La 3+ , 17 Mn 2+ , 16 Fe 3+ , 18 and Ni 2+ . 19 The effect on the catalytic activity by tuning the porosity, surface area, surface charge, acidity/basicity, and softness by choosing the suitable metal ion has been outlined.…”

“…Various MOFs based on the 1,4 dicarboxylic acid benzene (1,4-BDC) linker, resulting in M-1,4-BDC, have been synthesized by changing the metal ion, such as Zn 2+ , 14 Cu 2+ , 15 Co 2+ , 16 La 3+ , 17 Mn 2+ , 16 Fe 3+ , 18 and Ni 2+ . 19 The effect on the catalytic activity by tuning the porosity, surface area, surface charge, acidity/basicity, and softness by choosing the suitable metal ion has been outlined.…”

“…Compared to other porous materials, such as zeolites and porous carbons, MOFs are unique in terms of their exceedingly high porosities, tunable pores, and diverse functionalities. , MOFs with well-dispersed metal sites feature better electrocatalytic activity , than conventional metal oxides, , hydroxides, , metal sulfides, and metal phosphides. , The versatility of MOF composition by simply changing the metal ion (i.e., size, acidity, softness) and functional ligand (i.e., polarity, length, hydrophobicity) makes tuning their properties for OER possible. Various MOFs based on the 1,4 dicarboxylic acid benzene (1,4- BDC) linker, resulting in M-1,4-BDC, have been synthesized by changing the metal ion, such as Zn 2+ , Cu 2+ , Co 2+ , La 3+ , Mn 2+ , Fe 3+ , and Ni 2+ . The effect on the catalytic activity by tuning the porosity, surface area, surface charge, acidity/basicity, and softness by choosing the suitable metal ion has been outlined. , It remains challenging to completely balance the adsorption energetics of different oxo-intermediates for high-performance oxygen reduction reaction (ORR) and OER using MOFs, which resulted from the lack of understanding of active sites and catalytic mechanisms.…”

Gas Sorption Properties of a New Three-Dimensional In-ABDC MOF With a Diamond Net

“…There are several MOF systems containing a ditopic azobenzene-4,4'-dicarboxylate (ABDC 2− ) bridging ligand in which the azo group (-N=N-) can potentially act as Lewis basic sites (Nguyen et al, 2011;Zhuang et al, 2011;Lyndon et al, 2013;Gong et al, 2015;Liu et al, 2016;Zhao et al, 2016;Yuan et al, 2017;Xu et al, 2018;Yang et al, 2018). We expected that the assembly between In III ions with ABDC 2− bridging ligands could lead to a new In-MOF with openly accessible azogroup-based Lewis basic sites from the bridged ABDC 2− ligands.…”

Series of Mn(II)/Mg(II)/Zn(II) Coordination Polymers with Azo/Alkene Functionalized Ligands

“…This provides us with the opportunity to keenly select the precursors, keeping the application in mind. A large number of MOFs or CPs were reported using various carboxylate ligands with transition metal ions. , However, very few structures with azo-functionalized (ABDCA) or stilbene dicarboxylic (SDCA) ligands are reported. − The success of the formation of MOFs or CPs by using ABDCA ligand is limited. , It might be due to the instability of ABDCA under solvothermal methods at a higher temperature . Azobenzene derivatives have gained popularity due to their distinctive photophysical properties and immense utilization in photoresponsive materials, and nonlinear optics. − Azobenzene or stilbene and its derivatives can be used as potential functional materials due to the possibility of trans to cis photoisomerization that results in significant modification in properties, such as color, dielectric constant, dipole moment, etc. − ,− Here we have used ABDCA and SDCA as ligands to synthesize alkaline earth and transition metal ions based functional materials with a hierarchy of structures.…”