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ABSTRACT: An expanded 4,4-paddlewheel-connected porous MOF-505-type metal-organic framework (MOF), [Cu2(PDEB)(H2O)2]·xS (NJU-Bai12; NJU-Bai represents the Nanjing University Bai group and S represents noncoordinated solvent molecules) has been designed from a nanosized rectangular diisophthalate linker containing alkyne groups 5,5'-(1,4-phenylenedi-2,1-ethynediyl)bis(1,3-benzenecarboxylic acid). This MOF material possesses permanent microporosity with the highest Brunauer-Emmett-Teller surface area of 3038 m2·g-1 and the largest unsaturated total hydrogen storage capacity of 62.7 mg·g-1 at 77 K and 20 bar among reported MOF-505 analogues. Additionally, NJU-Bai12 also exhibits excellent carbon dioxide (CO2) uptake capacity (23.83 and 19.85 mmol·g-1 at 20 bar for 273 and 298 K, respectively) and selective gas adsorption properties with CO2/CH4 selectivity of 5.0 and CO2/N2 selectivity of 24.6 at room temperature.
Inorganic Chemistry 03/2013; · 4.60 Impact Factor
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ABSTRACT: An amide-inserted metal-organic framework (NJU-Bai3) presents high storage and high selectivity toward CO(2) and combines these two interesting characters which strongly support our expectation that amide groups can significantly enhance the CO(2) binding ability and selectivity of MOFs.
Chemical Communications 02/2012; 48(25):3058-60. · 6.17 Impact Factor
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ABSTRACT: Two mesoporous and flexible acylamide-functionalized rht-type MOFs exhibit not only high excess unsaturation CO(2) uptake (157 wt%) at 20 bar and 273 K, but also good selectivity of CO(2)/CH(4) (8.6) and CO(2)/N(2) (34.3). The advantages of acylamide groups for CO(2) capture have been further confirmed by GCMC and first-principles calculations.
Chemical Communications 02/2012; 48(56):7025-7. · 6.17 Impact Factor
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ABSTRACT: For the first time, the shifting degree of pcu-type interpenetrated framework was well controlled by employing a modulator and changing the temperature, in which their evacuated samples are almost non-crystalline products with different meso- and microstructures, resulting in different hydrogen adsorption properties.
Chemical Communications 03/2011; 47(9):2556-8. · 6.17 Impact Factor
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ABSTRACT: An rht-type metal-organic framework (MOF) prepared from M(2)(carboxylate)(4) (M = Cu, Co) paddlewheel clusters and a flexible C(3)-symmetric hexacarboxylate ligand with acylamide groups exhibits larger CO(2) uptake, an enhanced heat of adsorption, and higher selectivity toward CO(2)/N(2) in comparison with what was previously observed for an analogous MOF with alkyne groups.
Journal of the American Chemical Society 02/2011; 133(4):748-51. · 9.91 Impact Factor
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ABSTRACT: Structure and properties (energies, electronic, and thermodynamic properties) of complexes pyridine-XY (X, Y = F, Cl, Br) have been investigated at the MP2/aug-cc-pVDZ level. Two types of geometries (pi-halogen bonded and sigma-halogen bonded) are observed. In contrast with the previous results on similar furan and thiophene complexes, the sigma-halogen bonded structures are more stable and the reasons are discussed. Charge transfer is found to be important in the formation of title system and the possible existing complexes under experimental conditions have been forecasted too. A symmetry-adapted perturbation theory energy decomposition analysis reveals that the pyridine-XY complexes are dominantly inductive in nature.
The Journal of chemical physics 04/2010; 132(16):164104. · 3.09 Impact Factor
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ABSTRACT: To understand the effects of pyrazole substitution on reaction equilibrium, the interactions between a series of pyrazole-like ligands and [OV(O(2))(2)(D(2)O)](-)/[OV(O(2))(2)(HOD)](-) were explored by using multinuclear ((1)H, (13)C, and (51)V) magnetic resonance, HSQC, and variable temperature NMR in 0.15 mol/L NaCl ionic medium mimicking physiological conditions. These results show that the relative reactivities among the pyrazole-like ligands are 3-methyl-1H-pyrazole approximately 4-methyl-1H-pyrazole approximately 1H-pyrazole>1-methyl-1H-pyrazole. As a result, the main factor which affects the reaction equilibrium is the steric effect instead of the electronic effect of the methyl group of these ligands. A pair of isomers has been formed resulting from the coordination of 3-methyl-1H-pyrazole and a vanadium complex, which is attributed to different types of coordination between the vanadium atom and the ligands. Thus, the competitive coordination leads to the formation of a series of six-coordinate peroxovanadate species [OV(O(2))(2)L](-) (L, pyrazole-like ligands). Moreover, the results of density functional calculations provided a reasonable explanation on the relative reactivity of the pyrazole-like ligands as well as the important role of solvation in these reactions.
Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 03/2010; 75(3):1095-9. · 2.10 Impact Factor
