Mesoporous metal-organic frameworks applications

Series of Special Issues cover various aspects of microporous molecular sieves, metal-organic frameworks and ordered mesoporous materials. Synthesis principles, templating, formation mechanisms, characterization methods, functionalization strategies, and applications are discussed in excellent and comprehensive review articles and more specific research reports. 

Rossini el al. have reported the first application of DNP-enhanced solid-state NMR spectroscopy to metal-organic frameworks (MOF) materials." The experiments are demonstrated on the N-functionalized MOF compound (In)-MIL-68-NH2 (1), on a partially functionalized variant of 1 with a terephthalate aminoterephthalate ratio of 80 20 (2), and on a 10% pro-line-functionalized derivative of 1, (In)-MIL-68-NH-Pro (3). Despite the fact that the pore size of the MOFs are much smaller (ca. 1.6 nm) than that of the mesoporous materials previously investigated by DNP surface-enhanced solid-state NMR (ca. 6 nm), it has been shown that significant effective sensitivity enhancement factors can be obtained for H- C CPMAS experiments on these MOF materials. These factors are discussed with respect to the presence or not of the bulky proline ligand, which prevents the radical from entering into the pores. The authors show in addition that the reduction in experimental time provided by the DNP technology (of the order of 10- to 30-fold) allows the fast acquisition of two-dimensional H- C correlation spectra and of H- N CPMAS NMR spectra at natural abundance. 

B. Zornoza, C. Tellez, J. Coronas, J. Gascon, F. Kapteijn, Metal organic framework based mixed matrix membranes an increasingly important field of research with a large application potential, Microporous Mesoporous Materials 166 (2013) 67-78. 

Although catalysis is potentially one of the most important applications of metal-organic porous materials, as was the case for microporous zeolites and mesoporous materials, only a handful of examples have been so far reported for MOFs [128-131]. For catalytic applications using metal-organic open-framework materials, apparently five types of catalyst systems or active sites have been utilized ... 

The number of publications concerning utilization of the EISA process for fabrication of different structured materials is counted in the hundreds, which is far beyond the possibilities of this chapter to review in depth. Rather, we intend to provide a brief introduction into EISA and its application to the fabrication of functional thin films for electronic applications (e.g., electro-chromic layers and solar cells), with a special focus on fabrication of crystalline mesoporous films of metal oxides. Attention will also be given to techniques used to evaluate the pore structure of the thin films. For the other aspects of the EISA process, for example its mechanism,4 strategies for preparation of crystalline porous metal oxides,5 mesoporous nanohybrid materials,6 periodic organic silica materials,7,8 or postgrafting functionalization of mesoporous framework,9 we kindly recommend the reader to refer to the referenced comprehensive reviews. 

Much effort has thus been expended in two other directions. Many mesoporous silicates have been prepared containing silicon and a second element, e. g. titanium, vanadium, zirconium, and a range of other first row transition metals, and their uses in catalysis have been examined [14-16]. The scope of this section is, however, to cover organic modification of the silica framework, both by postsynthesis grafting and in-situ functionalization, and to discuss applications of the products as basic catalysts. 

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