The metal-organic frameworks NOTT-400 and NOTT-401, based on a binuclear [Sc(2)(μ(2)-OH)(O(2)CR)(4)] building block, have been synthesised and characterised; the desolvated framework NOTT-401a shows a BET surface area of 1514 m(2) g(-1) with a total H(2) uptake of 4.44 wt% at 77 K and 20 bar.

A continuous flow process for the synthesis of a metal-organic framework using only water as the reaction medium and requiring only short residence times is described. This affords a new route to scale-up of materials incorporating many of the principles of green chemistry.The process is demonstrated by the synthesis MIL-53(Al) via continuous flow reaction requiring only 5-6 minutes with a space time yield of 1300 kg m -3 d -1 . We have demonstrated the synthesis of 500 g of MIL-53(Al) using this process, which can be scaled-up further by simply feeding further solutions of metal salt and ligand through the reactor. The product has a higher surface area and a better colour than a commercially produced sample of this MOF.In addition, a new and effective method for the extraction of terephthalic acid from within the pores of MIL-53(Al) using supercritical ethanol has been developed, representing a new methodology for activation and removal of substrates from porous hosts.___________________________________________________________________________

Water and ethanol stabilities of the crystal structure of the Cu-based metal-organic framework (MOF) HKUST-1 have been investigated. Vapour (water and ethanol) sorption isotherms and cyclability were measured by a dynamic strategy. The ethanol sorption capacity of HKUST-1 at 303 K remained unchanged contrasting water sorption (which decreased along with the sorption experiment time). Considering the binding energy of each sorbate with the open Cu(ii) sites, obtained by the use of diffusion coefficients, we showed the superior crystal stability of the HKUST-1 framework towards ethanol. Finally, a small quantity of ethanol (pre-adsorbed) slightly enhanced CO capture without crystal structure degradation.

MIL-101(Cr)-4F(1%) shows a high uptake and high chemical stability to dry and humid SO2 and a remarkable cyclability. In situ DRIF spectroscopy upon the adsorption of CO identified the preferential adsorption sites for this MOF material.

Sol–gel processing represents a powerful and versatile strategy for the preparation of functional inorganic and hybrid materials that facilitate control over the molecular composition, as well as organization of the materials at the various length scales relevant to fundamental and applied research. Recent advances have enabled its use for the processing of an emerging class of functional porous materials called metal–organic frameworks (MOFs). Here, sol–gel approaches can be employed for the direct manipulation of MOFs, or as a route to the construction of composite materials where the properties of the MOF are synergistically combined with those of a carefully chosen inorganic phase. In this review, we present the most significant progress made in this emerging area, according to four main synthetic strategies, with a particular focus on describing how sol–gel processing enhances the functionalities of the MOF. These strategies include (1) molecular scale manipulations of the pore surfaces of MOFs with sol–gel precursors; (2) the controlled positioning or growth of MOF crystals on inorganic surfaces; (3) the use of MOF crystals as templates for sol–gel processes (either within the pores, or at the external surfaces); and (4) the use of sol–gel-derived sacrificial inorganic templates for the structuring of MOF-based architectures. Each of these processing methods imparts unique properties to the systems and provides a route to higher-order architectures and material compositions not accessible through conventional approaches to MOF synthesis. Sol–gel processing provides promising routes toward new functional materials that display enhanced properties and are expected to play an important role in allowing MOFs to be optimized for specific applications.

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Two new three-dimensional Sc(III) metal-organic frameworks {[Sc(3)O(L(1))(3)(H(2)O)(3)]·Cl(0.5)(OH)(0.5)(DMF)(4)(H(2)O)(3)}(∞) (1) (H(2)L(1)=1,4-benzene-dicarboxylic acid) and {[Sc(3)O(L(2))(2)(H(2)O)(3)](OH)(H(2)O)(5)(DMF)}(∞) (2) (H(3)L(2)=1,3,5-tris(4-carboxyphenyl)benzene) have been synthesised and characterised. The structures of both 1 and 2 incorporate the trinuclear trigonal planar [Sc(3)(O)(O(2)CR)(6)] building block featuring three Sc(III) centres joined by a central μ(3)-O(2-) donor. Each Sc(III) centre is further bound by four oxygen donors from four different bridging carboxylate anions, and a molecule of water located trans to the μ(3)-O(2-) donor completes the six coordination at the metal centre. Frameworks 1 and 2 show high thermal stability with retention of crystallinity up to 350 °C. The desolvated materials 1a and 2a, in which the solvent has been removed from the pores but with water or hydroxide remaining coordinated to Sc(III), show BET surface areas based upon N(2) uptake of 634 and 1233 m(2) g(-1), respectively, and pore volumes calculated from the maximum N(2) adsorption of 0.25 cm(3) g(-1) and 0.62 cm(3) g(-1), respectively. At 20 bar and 78 K, the H(2) isotherms for desolvated 1a and 2a confirm 2.48 and 1.99 wt% total H(2) uptake, respectively. The isosteric heats of adsorption were estimated to be 5.25 and 2.59 kJ mol(-1) at zero surface coverage for 1a and 2a, respectively. Treatment of 2 with acetone followed by thermal desolvation in vacuo generated free metal coordination sites in a new material 2b. Framework 2b shows an enhanced BET surface area of 1511 m(2) g(-1) and a pore volume of 0.76 cm(3) g(-1), with improved H(2) uptake capacity and a higher heat of H(2) adsorption. At 20 bar, H(2) capacity increases from 1.99 wt% in 2a to 2.64 wt% for 2b, and the H(2) adsorption enthalpy rises markedly from 2.59 to 6.90 kJ mol(-1).

PCM-10 is a porous phosphine coordination material based on Ca(II) and tris(p-carboxylated) triphenylphosphine. The material provides a unique 3-dimensional surface of P(III) Lewis base sites, which is ideal for post-synthetic functionalization. The addition of Au(I) yields an advanced material that can selectively adsorb 1-hexene over n-hexane at room temperature.