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Reduction of atmospheric carbon dioxide, which is one of the main components affecting global warming, and hydrogen storage as a renewable energy source by effective sorbents are considered to be vital challenges. In this work, a nanoporous pillared-layered metal–organic framework of [Zn2(TDC)2(DABCO)]·(DMF)4(1) (TDC2–= thiophene-2,5-dicarboxylate, DABCO = 1,4-diazabicyclo[2.2.2]octane, and DMF = N,N-dimethylformamide) as a sorbent was synthesized by several methods, and its structure was determined by single-crystal X-ray analysis. Then, its physicochemical characteristics were investigated by using a set of analyses. The potential of 1in capturing nitrogen, hydrogen, and carbon dioxide gases at different temperatures showed that the product made by the sonochemical method has a higher capacity for adsorption due to a larger surface area compared to the products of other methods. The maximum capacity of carbon dioxide adsorption is 1.97 mmol·g–1at 273 K and 1 bar, displaying good MOF performance at low pressures. Also, the hydrogen storage capacity of 1is higher than several well-known MOFs, such as ZIF-8, MOF-508, and PCN-13, under similar conditions. Moreover, the isosteric heat of carbon dioxide adsorption was calculated at low coverage, revealing the interaction nature between the sorbent surface and gas molecules and the resulting dependence of sorption on the temperature. The better performance of 1in adsorbing CO2and H2molecules compared to some reported MOFs may be related to the surface of the pores decorated with hetero atoms of sulfur.

Today, due to the momentary release of carbon dioxide and increasing global heat, solutions that prevent the release of this greenhouse gas into the atmosphere are very important. In this work, a nanoporous sorbent with a 3D framework and chemical formula of [Ca1.5(FDC)1.5(DMF)] (MUT-13) (FDC2–= furan-2,5-dicarboxylate, DMF= N,N-dimethylformamide) was prepared in different synthetic routes. Single crystal of MUT-13was identified by X-ray crystallographic analysis and other physicochemical analyses. Then, with the help of GCMC, the performance of MUT-13was simulated in the adsorption of various gases (CO2, H2, C2H2, CH4, and N2) under different temperature and pressure conditions. Also, the potential of MUT-13in separating carbon dioxide from binary mixtures (CO2/CH4, CO2/N2, CO2/H2and CO2/C2H2) was investigated. The results indicated that the sorption structure has a high capacity to adsorb carbon dioxide (6.2 mmol.g–1) and acetylene (5.5 mmol.g–1) molecules in environmental conditions. It also shows a separation greater than 5000 and 2000 for the mixture of CO2:H2at low and high pressures, respectively. This good performance of MUT-13in adsorbing and separating carbon dioxide compared to other MOF-based adsorbents can be related to the surface of its pores decorated by the heteroatom of the ligand and the presence of unsaturated metal centers in its structure.

A new metal–organic framework with a three-dimensional (3D) nanoporous structure was formed from the self-assembly of 2,5-thiophenedicarboxylic acid (H2TDC) with Mn(NO3)2·4H2O in dimethylacetamide (DMA). It crysallizes in the monoclinic crystal system with the space group C2/cand 1D channels in the baxis direction with the chemical formula of [Mn4(TDC)4(DMA)3(H2O)2]n(MUT-5). The synthesis of MUT-5 by three methods was performed by optimizing reaction conditions such as the reaction time and temperature, and their effects on the morphology and yield of the products were investigated. The physicochemical properties and crystalline structure were characterized by single-crystal X-ray crystallography, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and N2adsorption/desorption. The results revealed that the utilization of sonochemical method gives sufficient yield with enhanced properties such as uniform particles of less than 100 nm, a higher surface area, and better capacity in nitrogen capture (82.6 cm3g–1at 77 K and 1 bar) relative to the other two methods. Moreover, due to the presence of electroactive sulfur heteroatoms and open metal coordination sites in the channels of MUT-5, it provides strong binding sites for CO2adsorption of 1.14 mmol g–1at 298 K and 1 bar, which is higher than the adsorption capacities of other famous MOFs. Thereby it is a promising match for carbon dioxide storage and capture.