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Design, synthesis, and control of metrics, functionality, and interpenetration in metal-organic frameworks and their application in hydrogen storage

Posted on:2004-06-29Degree:Ph.DType:Thesis
University:University of MichiganCandidate:Rosi, Nathaniel LouisFull Text:PDF
GTID:2461390011476178Subject:Chemistry
Abstract/Summary:
This thesis reports the isolation of both the interpenetrated [Zn4O(TPDC)3•(DEF)(H2O)5 (IRMOF-15)] and non-interpenetrated [Zn4O(TPDC)3•(DEF) 17(H2O)2 (IRMOF-16)] forms of identical frameworks, demonstrating for the first time that interpenetration can be avoided even when it is topologically allowed. Additionally, a second series of frameworks, MOF-69A-C [Zn3(BPDC)2(OH)2•(DEF) 2(H2O)2 (MOF-69A), Zn3(OH)2(2,6-NDC) 2•(DEF)2(H2O)2 (MOF-69B), and Zn3(OH)2(BDC)2•(DEF)2(H 2O)2 (MOF-69C)] was synthesized. The unique aspect of these frameworks is the presence of rod building units that result in an underlying framework topology that forbids interpenetration, regardless of linker length. Rod building units were also identified in MOFs-71-73 [Co(BDC)(DMF) (MOF-71), Mn1.5(BDC)1.5(DEF) (MOF-72), Cd3(1,3-BDC) 4•(Me2NH2)2 (MOF-73)]. Coupled with MOF-69A-C, MOFs-71-73 prompted consideration of new design strategies for the construction of stable, porous MOFs based on rod building units. Sorption studies indicate that MOF-72 is a microporous material, proving that rod-based MOF assemblies can indeed be highly stable.; This thesis also presents a study that relates SBU dimension to pH of reaction and shows specifically that the dimension of the SBU can increase with increasing pH. The description of Zn3(1,4-BDC)4•(DEF) 2(Et2NH2)2(Et2NH)1.5 (MOF-144) is detailed in these studies. In addition, this thesis uses knowledge of SBU formation to design MOFs with functionalized links: Zn 3(TCPP)(H2O)2(DEF)2•(DEF) 11(H2O)11 (MOF-122) is the first microporous MOF that contains a porphyrin linker and Zn4O(C26H 18O4)3•(DEF)14(H2O) 13.5 (IRMOF-17) is one of the first examples of a designed homochiral 3-D MOF.; Finally, inelastic neutron scattering spectroscopy of hydrogen sorbed Zn4O(C8H4O4)3 (MOF-5) was used to identify the interactions between the adsorbed hydrogen molecules and the framework. It was found that favorable interactions exist between the adsorbed hydrogen and both the framework zinc atoms and the 1,4-benzenedicarboxylate linkers (C8H4O4). Moreover, it was shown that the linkers contain several hydrogen binding sites. It was then shown that Zn4O(C12H6O4)3 (IRMOF-8), which has a larger naphthalene linker, has quadruple the hydrogen uptake of MOF-5 (2.0 wt. %) at room temperature and 10 bar.
Keywords/Search Tags:Hydrogen, MOF, Frameworks, Def, Thesis, Rod building units, Interpenetration
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