Nanoscale MOFs

Certain types of reactions, such as polymerization, in the confined nanoscale channels/space may have different pathways compared with those in open space. Kitagawa and coworkers have utilized size-tunable MOFs as reactions hosts for radical polymerization of activated monomers, such as styrene, divinylbenzene, substituted acetylenes, methyl methacrylate, and vinyl acetate (Fig. 11) [32-35]. Fara-dicarboxylate linkers of different sizes, a-d, were used to link Cu " and Zn " centers to form 2D sheets which were further linked by triethylenediamine to form 3D frameworks 9a-d (for Cu " ) and lOb-d (for Zn " ) that possess 1-D channels (Fig. 12). 

It should be noted that, due to their great similarity to zeolites, MOFs can have the same area of applications. In particular, owing to their fascinating structures and unusual properties, such as permanent nanoscale porosity (up to 90 % free volume), high surface area, tunable pore size, adjustable... 

It is first important to classify the different types of nanostructures and their relevant characteristics and morphological features at the nanoscale, according to their dimensionality, as illustrated in Fig. 4.1. One can clearly distinguish OD nanostructures with nanoparticles, clusters and mesoporous systems as MOFs (Metal Oxide Frameworks), ID nanostmctures with nanotubes and nanowires, 2D nanostructures with multilayers and 3D nanostructures with nanostructured and nanocrystalline materials. In this context, nanocrystalline materials are defined as single- or multi-phase polycrystaUine solids with a grain size of a few nanometres... 

Standing upon the above understanding for usual nanospace, we now, in this study, seek unique characteristics of phase behavior of simple fluids confined in nanoscale coordination space, or metal-organic framework (MOF), employing molecular simulation technique. 

Recently, the use of nanoscale lanthanide MOFs for biological and biomedical applications has attracted increasing attentions. The interest of these functional materials relies on the combination of the chemical or biofunctional behavior of MOFs and the unique luminescence properties of lanthanide ions, such as high photostability, long decay rates, large Stokes shifts, and narrow emission bands. Besides their luminescent characteristics, lanthanide MOFs can possess paramagnetic properties which help to increase the relaxation rate of water protons in the... 

Although MOFs show high promise for many of the aforementioned research areas, they do not always fulfill the relevant requirements for specific applications. For some applications MOFs must be miniaturized and the resulting miniaturized MOFs must be integrated onto surfaces. Miniaturization of MOFs down to the submicrometer regime (100-1000 nm), and further down, to the nanoscale (1-lOOnm), is very important, as it bridges the gap between current MOF science and device-material... 

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