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We report the facile synthesis of aluminum-based metal-organic frameworks (MOFs) with different morphologies and structures by tuning the OH− content in the reaction solution. MIL-96 crystals with dodecahedral and hexagonal column shapes were successfully synthesized by tuning the OH− ion content of the synthesis solution. When the OH− ion content was further increased, MIL-110 with a nanorod morphology appeared as the product. For the first time, we obtained pure MIL-96 and MIL-110 under basic conditions directly by using the 1,3,5-benzenetricarboxylic acid (btc) linker. All samples show significant , with a decomposition temperature above 300 °C. We found that the gas adsorption properties of MIL-96 were directly dominated by the crystal morphology. At 0.4 °C and 30 bar, the dodecahedral and hexagonal MIL-96 samples can adsorb 9.3 and 6.5 mmol g−1 CO2, respectively, although they possess similar surface areas and identical crystalline structures. The MIL-110 nanorod shows a CO2 adsorption capacity of up to 16 mmol g−1 under the same conditions. [ABSTRACT FROM AUTHOR]

In metal-organic framework (MOF) chemistry, polar functionalities greatly affect the gas adsorption properties. However, synthesis of MOFs with desired functionality is very challenging because many chemical functionalities cannot be achieved under the conditions for MOF assembly. Herein, a facile synthesis of new functionalized two-dimensional MOFs with preferential CO2 capture is presented, which uses two successive synthesis steps: 1) rational design and template-free synthesis of the parent MOF with designated pendant amino groups and 2) postsynthetic modification of the active amino groups with acetic acid and trimesoyl chloride functionalities. The only variation in structure arises from the functional groups of these materials. Experimental results demonstrate that the three 2D layered MOFs have remarkable thermal stability and moisture resistance, which are particularly advantageous for practical CO2 capture. Although their surface areas are moderate (270-340 m2 g−1), they still have excellent CO2 adsorption capacity (up to 2.9 mmol g−1 at 1 bar and 273 K) comparable to that of previously reported MOFs with much higher surface areas. Based on first-principles calculations, it is shown that the acidic carbonyl functionalities in addition to the amino groups are also favorable to bind CO2 molecules. The adsorption sites generated from polar functionalities are key factors leading to high CO2 uptake. [ABSTRACT FROM AUTHOR]

A thin and compact mixed matrix membrane containing CAU-1-NH2 and the poly(methyl methacrylate) polymer has been originally synthesized. The as-prepared membrane exhibits high permeability of H2 and excellent H2/CO2 selectivity. [ABSTRACT FROM AUTHOR]

Solid porous dual amine-decorated metal–organic framework (MOF) adsorbents with tunable porosity have been prepared. The adsorbents exhibit remarkable CO2/CH4 selectivity and CO2 adsorption capacity at low pressures. [ABSTRACT FROM AUTHOR]

Abstract: A thin and compact mesoporous MCM-48 membrane had been successfully synthesized on vacuum-coated α-Al2O3 support with pore size of 1μm. The pretreated supports and the membranes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and single gas permeation test. The pretreated supports were gas permeable for N2 and the as-synthesis membrane was gas tight, indicating that the defects left in the vacuum step disappeared in the multi-hydrothermal synthesis process. The XRD pattern of the membrane was represented to the typical cubic space group. And the SEM images showed that the membrane was continuous and 4-μm thick. Additionally, the separation factor of the calcined membrane for H2/N2 was up to 3.33 and the Knudsen contribution to the total flux for N2 permeation was 97.8%. All the results indicated that the good surface conditions of the large-pore supports improved by the vacuum coating method were favorable for the formation of a compact MCM-48 membrane on it. [Copyright &y& Elsevier]

We report the facile synthesis of aluminum-based metal-organic frameworks (MOFs) with different morphologies and structures by tuning the OH(-) content in the reaction solution. MIL-96 crystals with dodecahedral and hexagonal column shapes were successfully synthesized by tuning the OH(-) ion content of the synthesis solution. When the OH(-) ion content was further increased, MIL-110 with a nanorod morphology appeared as the product. For the first time, we obtained pure MIL-96 and MIL-110 under basic conditions directly by using the 1,3,5-benzenetricarboxylic acid (btc) linker. All samples show significant thermal stability, with a decomposition temperature above 300 °C. We found that the gas adsorption properties of MIL-96 were directly dominated by the crystal morphology. At 0.4 °C and 30 bar, the dodecahedral and hexagonal MIL-96 samples can adsorb 9.3 and 6.5 mmol g(-1) CO2, respectively, although they possess similar surface areas and identical crystalline structures. The MIL-110 nanorod shows a CO2 adsorption capacity of up to 16 mmol g(-1) under the same conditions., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)