Surface metal-organic frameworks

PL photoluminescence SURMOF surface metal organic framework... 

Water stability is a major challenge that has to be overcome before metal organic framework can be used in removing carbon dioxide from flue gas. The core structure of MOF reacts with water vapor content in the flue gas leading to severe distortion of the structure and even failure. As a consequence, the physical structure of MOF is changed, e.g., reduction of porosity and surface area, etc. that decreases the capacity and selectivity for C02. Complete dehydration of flue gas increases the cost of separation. It is therefore essential for MOFs to exhibit stability in the presence of water up to certain extent [91]. 

Physisorption (i.e., adsorption of hydrogen) of molecular hydrogen by weak van der Waals forces to the inner surface of a highly porous material. Adsorption has been studied on various nanomaterials, e.g., nanocarbons, metal organic frameworks and polymers. 

The above requirements directed our attention to the specific surface features of Metal Organic Frameworks (MOF) [6,7] and graphite oxides (GO) [8,9]. The former are... 

Petit C, Bandosz TJ Enhanced adsorption of ammonia on Metal-Organic Framework / graphite oxide composites analysis of surface interactions, Adv. Fund. Mater. 2009,19,1-8. 

Since the strategy was initially based on catalytic purposes, the surfaces considered initially were mostly (i) highly divided oxides (here are included simple oxides, mixed oxides, zeoUtic materials, mesoporous systems, hybrid organic inorganic materials, metal organic frameworks, etc.) and (ii) highly divided metals (supported or unsupported small metal particles). 

Type I isotherms are characteristic of microporous solids having relatively small external surface area (activated carbons, molecular sieve zeolites, metal organic frameworks, etc.). They are usually obtained by most gases and vapors on activated carbons. 

Fig. 7 Left The metal-organic framework ZIF-100 Zn atoms are shown as blue, while the imidazolate ligands are represented simply as black rods. The defined inner space of the framework is 35.6 by 67.2 A, with a surface area of 595 m2 g-1. Right These giant cages are part of a larger (but equally symmetric) superstructure [15]. Reprinted by permission from Macmillan Publishers...

The record holders for surface area per gram and for gas storage are materials prepared by Yaghi and coworkers that they call metal-organic frameworks (MOFs). The first of these MOFs [14] looked much like the Robsen design. Increasingly, these beautiful structures, with dramatically increased porosity, look like a vision of Escher s (Fig. 7). 

Figure 13.15 Schematic representation of synthesis and surface modification of nanoparticles [54]. (Reproduced with permission from W.J. Rieter et al., Surface modification and functionalization of nanoscale metal-organic frameworks for controlled release and luminescence sensing, Journal of the American Chemical Society, 129, 9852-9853, 2007. 2007 American Chemical Society.)...

Metal-organic frameworks with large surface areas, controlled pore sizes, and easy functionalization of the organic part have a high potential in a variety of practical applications molecular sorption, catalysis, gas separation, molecular... 

B. Chen, M. Eddaoudi, S.T. Hyde, M. O Keeffe, and O.M. Yaghi, Interwoven Metal-organic Framework on a Periodic Minimal Surface with Extra-large Pores. Science, 2001, 291, 1021-1023. 

Chen, B.L. Eddaoudi, M. Hyde, S.T. O Keeffe, M. Yaghi, O.M. Interwoven metal-organic framework on a periodic minimal surface with extra-large pores. Science 2001, 291 (5506), 1021-1023. 

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