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The development in the field of coordination polymers or metal-organic coordination networks, MOCNs (metalorganic frameworks, MOFs) is assessed in terms of property investigations in the areas of catalysis, chirality, conductivity, luminescence, magnetism, spin-transition (spin-crossover), non-linear optics (NLO) and porosity or zeolitic behavior upon which potential applications could be based.

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Research into extended porous materials such as metal-organic frameworks (MOFs) and porous organic frameworks (POFs), as well as the analogous metal-organic polyhedra (MOPs) and porous organic cages (POCs), has blossomed over the last decade. Given their chemical and structural variability and notable porosity, MOFs have been proposed as adsorbents for industrial gas separations and also as promising filler components for high-performance mixed-matrix membranes (MMMs). Research in this area has focused on enhancing the chemical compatibility of the MOF and polymer phases by judiciously functionalizing the organic linkers of the MOF, modifying the MOF surface chemistry, and, more recently, exploring how particle size, morphology, and distribution enhance separation performance. Other filler materials, including POFs, MOPs, and POCs, are also being explored as additives for MMMs and have shown remarkable anti-aging performance and excellent chemical compatibility with commercially available polymers. This Review briefly outlines the state-of-the-art in MOF-MMM fabrication, and the more recent use of POFs and molecular additives.

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The defined synthesis of OMS in MOFs is the basis for targeted functionalization through grafting, the coordination of weakly binding species and increased (supramolecular) interactions with guest molecules.

Mixed-matrix membranes (MMMs) with metal-organic frameworks (MOFs) as additives (fillers) exhibit enhanced gas permeabilities and possibly also selectivities when compared to the pure polymer. Polyimides (Matrimid®) and polysulfones are popular polymer matrices for MOF fillers. Presently investigated MOFs for MMMs include [Cu(SiF(6))(4,4'-BIPY)(2)], [Cu(3)(BTC)(2)(H(2)O)(3)] (HKUST-1, Cu-BTC), [Cu(BDC)(DMF)], [Zn(4)O(BDC)(3)] (MOF-5), [Zn(2-methylimidazolate)(2)] (ZIF-8), [Zn(purinate)(2)] (ZIF-20), [Zn(2-carboxyaldehyde imidazolate)(2)] (ZIF-90), Mn(HCOO)(2), [Al(BDC)(μ-OH)] (MIL-53(Al)), [Al(NH(2)-BDC)(μ-OH)] (NH(2)-MIL-53(Al)) and [Cr(3)O(BDC)(3)(F,OH)(H(2)O)(2)] (MIL-101) (4,4'-BIPY = 4,4'-bipyridine, BTC = benzene-1,3,5-tricarboxylate, BDC = benzene-1,4-dicarboxylate, terephthalate). MOF particle adhesion to polyimide and polysulfone organic polymers does not represent a problem. MOF-polymer MMMs are investigated for the permeability of the single gases H(2), N(2), O(2), CH(4), CO(2) and of the gas mixtures O(2)/N(2), H(2)/CH(4), CO(2)/CH(4), H(2)/CO(2), CH(4)/N(2) and CO(2)/N(2) (preferentially permeating gas named first). Permeability increases can be traced to the MOF porosity. Since the porosity of MOFs can be tuned very precisely, which is not possible with polymeric material, MMMs offer the opportunity of significantly increasing the selectivity compared to the pure polymeric matrix. Additionally in most of the cases the permeability is increased for MMM membranes compared to the pure polymer. Addition of MOFs to polymers in MMMs easily yields performances similar to the best polymer membranes and gives higher selectivities than those reported to date for any pure MOF membrane for the same gas separation. MOF-polymer MMMs allow for easier synthesis and handability compared to pure MOF membranes.

The adsorption/desorption of up to 0.75 g of water vapour per g of the porous MOFs 3D-{M 3 O(X)(H 2 O) 2 [btc] 2 $nH 2 O}, MIL-100 (M ¼ Al, Fe; X ¼ OH, F, btc ¼ benzene-1,3,5-tricarboxylate, trimesate), occurs at small relative pressures of p/p 0 < 0.4 and a comparatively small hysteresis. Together with very good cycle stability, these properties render both MIL-100(Al and Fe) very suitable candidates for thermally driven heat pumps or adsorption chillers.More than 50% of the energy consumption and, simultaneously, the CO 2 emissions of modern buildings originate from air conditioning processes. These are traditionally based on electrically driven, mechanical compression chillers and heat pumps or classical burner systems, respectively. This demand is expected to rise in the future because of increased living standards and global climate change. 1 However, with alternative technologies, less exergetic (that is, closer to equilibrium) forms of energy, even low-temperature waste heat from industrial processes, can be employed for both heating and cooling. Solar heat as driving energy is especially interesting due to the high coincidence of cooling demand and solar irradiation. While multiple working principles for thermally driven heat-pumps can be realised, the evaporation-adsorption method has proven most feasible for this purpose and is briefly described in Fig. 1 and Table 1.The presented process renders cooling applications independent of precious electrical energy. If it is used for heating, the incorporation of environmental heat allows for considerable fuel savings. The coefficient of performance (i.e. the relation between useful and driving heat), power density, cost and operating lifetime of the complete machine are governed by the sorption material and its figures of merit, i.e. porosity, water sorption capacity, hydrophilicity and hydrothermal stability. 2,3 The achievable loading lift and also the required desorption temperature directly depend on the hydrophilicity of the material, i.e., the p/p 0 value at which adsorption occurs