Microporous Metal–Organic Frameworks with High Gas Sorption and Separation Capacity

Abstract

The design, synthesis, and structural characterization of two microporous metal–organic framework structures, [M(bdc)(ted)0.5]·2 DMF·0.2 H2O (M = Zn (1), Cu (2); H2bdc = 1,4‐benzenedicarboxylic acid; ted = triethylenediamine; DMF: N,N‐dimethylformamide) is reported. The pore characteristics and gas sorption properties of these compounds are investigated at cryogenic temperatures, room temperature, and higher temperatures by experimentally measuring argon, hydrogen, and selected hydrocarbon adsorption/desorption isotherms. These studies show that both compounds are highly porous with a pore volume of 0.65 (1) and 0.52 cm3 g– 1 (2). The amount of the hydrogen uptake, 2.1 wt % (1) and 1.8 wt % (2) at 77 K (1 atm; 1 atm = 101 325 Pa), places them among the group of metal–organic frameworks (MOFs) having the highest H2 sorption capacity. [Zn(bdc)(ted)0.5]·2 DMF·0.2 H2O adsorbs a very large amount of hydrocarbons, including methanol, ethanol, dimethylether (DME), n‐hexane, cyclohexane, and benzene, giving the highest sorption values among all metal–organic based porous materials reported to date. In addition, these materials hold great promise for gas separation.

Molecular Simulation Study of CH4/H2 Mixture Separations Using Metal Organic Framework Membranes and Composites

“…18,44 Studies on adsorption and diffusion of gases in Zn(bdc)(ted) 0.5 are limited; Liu et al 18 reported the adsorption isotherms for H 2 in this MOF at 77 and 298 K using both experiments and molecular simulations. They also assessed the self-diffusivities and transport diffusivities of H 2 in Zn-(bdc)(ted) 0.5 using molecular dynamics and concluded that diffusion properties of H 2 in this MOF are comparable to those of H 2 in IRMOF-1 at room temperature.…”

Water adsorption in hydrophobic MOF channels

“…1,2 Though a very large number of materials with varying structures and chemistry have been synthesised, and the adsorption of a handful of gases is routinely performed along with structure characterisation, little data is available on water adsorption in MOFs. [3][4][5][6][7][8][9] Some MOFs, such as MOF-5 (also known as IRMOF-1), HKUST-1 and DUT-4, are unstable in the presence of water vapour. 10 Others, however, are stable even when left in liquid water for long periods of time.…”

Stability and Hydrolyzation of Metal Organic Frameworks with Paddle-Wheel SBUs upon Hydration

“…M(bdc)(ted) 0.5 has been shown to be an excellent absorbent for a variety of gases (H 2 , CO 2 , CH 4 and other hydrocarbons). [29][30][31] The paddle wheel binuclear metal clusters within M(bdc)(ted) 0.5 can be found in a large number of reported nanoframeworks materials with high microporosity, thermal stability, good sorption properties and other advanced functional properties such as magnetic property. [32][33][34][35][36][37] Using new pillaring or mixed ligands, it is possible to prepare a variety of functionalized and flexibly tuned 3D architectures by altering the nature of carboxylate and pillaring ligands.…”