| Abstract
| - The robust metal−organic framework compound {[Zn2(L)]·4H2O}∞I has been synthesized byhydrothermal reaction of ZnCl2 and 4,4‘-bipyridine-2,6,2‘,6‘-tetracarboxylic acid (H4L). Compound I crystallizesin a chiral space group, P42212, with the chirality generated by the helical chains of hydrogen-bondedguest water molecules rather than by the coordination framework. Removal of guest water molecules fromthe crystal affords the porous material, [Zn2(L)]∞ (II), which has very high thermal stability and is chemicallyinert. The N2 isotherm of II at 77 K suggests a uniform porous structure with a BET surface area of 312.7m2/g and a remarkably strong interaction with N2 molecules (βE0 = 29.6 kJ mol-1). II also exhibits significantgas storage capacities of 1.08 wt % for H2 at 4 bar and 77 K and 3.14 wt % (44.0 cm3/g, 67 v/v) formethane at 9 Bar at 298 K. The adsorption behavior of II toward organic solvent vapors has also beenstudied, and isotherms reveal that for different solvent vapors adsorption is dominated by two types ofprocesses, absorbate−absorbate or absorbate−absorbent interactions. The adsorption and desorptionkinetic processes in II are determined mainly by the molecular size of the guest species and their interactionwith the host.
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