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A strategy was developed to obtain from acetylenedicarboxylic acid either an acetylenedicarboxylate-based Zr metal-organic framework (MOF) with fcu topology or a halo-functionalized-MOF-801 through in situ ligand hydrohalogenation. The new materials feature exceptionally high hydrophilicity and CO /H adsorption energetics. The acetylenedicarboxylate linker and its functionalizable triple-bond discloses its potential in the engineering of microporous materials with targeted properties.

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Metal–organic frameworks (MOFs) currently receive high interest for cycling water adsorption applications like adsorption heat transformation for air-conditioning purposes. For practical use in adsorption heat pumps (AHPs), the microcrystalline powders must be formulated such that their high porosity and pore accessibility are retained. In this work, the preparation of millimeter-scaled pellets of MIL-160­(Al), Al-fumarate (Basolite A520), UiO-66­(Zr), and Zr-fumarate (MOF-801) is reported by applying the freeze granulation method. The use of poly­(vinyl alcohol) (PVA) as a binder reproducibly resulted in highly stable, uniformly shaped PVA/MOF pellets with 80 wt % MOF loading, with essentially unchanged MOF porosity properties after shaping. The shaped pellets were analyzed for the application in AHPs by water adsorption isotherms, over 1000 water adsorption/desorption cycles, and thermal and mechanical stability tests. Furthermore, the Al-fum pellets were applied in a fixed-bed, full-scale heat exchanger, yielding specific cooling powers from 349 up to 431 W/kg (adsorbent), which outperforms the current commercially used silica gel grains in AHPs under comparable operating conditions.

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Microwave-assisted dry-gel conversion (MW-DGC) combines the advantages of concentrated reactants in DGC with fast heating by microwave irradiation. This novel combination allows drastically decreasing the amount of solvent needed for synthesis and reaction times with the energy needed. Furthermore, MW-DGC allows for the recovery and re-use of the reaction solvent and thereby can significantly reduce the overall solvent waste in the syntheses of the four important MOFs MIL-100(Fe) (Basolite F300), UiO-66, MIL-140A and aluminium fumarate (Alfum, Basolite A520). All the MOF products obtained from MW-DGC showed satisfying yields, crystallinity and porosity in comparison with the industrial benchmarks Basolite F300 and Basolite A520. Moreover, MW-DGC also advantageously leads to a hierarchical micro-mesoporous Alfum material different to that from other synthesis methods.

Two new isostructural porous supramolecular materials {[Cu 2 (amp) 4 Cl][M(C 2 O 4 ) 3 ]•6H 2 O} n (amp = 2-aminomethylpyridine), designated as II and III for M = Cr(III) and M = Fe(III) respectively, have been synthesized by a self-assembly process of two ionic complexes [Cu 2 (amp) 4 Cl] 3+ and [M(C 2 O 4 ) 3 ] 3− , M = Fe(III) and Cr(III). They build heterometallic hydrogenbonded-, oxalato-and chlorido-bridged zigzag chains with interchain hydrogen bonds and π−π interactions. This results in supramolecular potentially porous architectures exhibiting large channels filled with hexameric water clusters. Their activated phases, II′ and III′, can readsorb the water molecules to regenerate the initial materials which are stable for many water adsorption and desorption cycles like that of their homologous catena-{ [(Co(amp) 3 ][Cr(C 2 O 4 ) 3 ]•6H 2 O} (I′). The three materials I′, II′, and III′ exhibit water adsorption and desorption isotherms having a sigmoidal shape and resulting in the combination of a type I(b) profile followed by an S-shaped type V isotherm with hysteresis. At 20 °C, the steep water sorption of the S-shaped isotherm occurs at 0.1P/P 0 for II′ and III′. This water sorption behavior is quite different from the related compound I′, where a gate opening and closure process is involved, giving a type V isotherm with a pronounced H1-type hysteresis loop with parallel and steep adsorption (at 0.25P/P 0 ) and desorption branches (at 0.17P/P 0 ). The water adsorption capacities of the three materials I′, II′, and III′ are 17, 12, and 11 wt %, respectively. Temperature does not have a great effect on their water sorption properties, and they all exclude N 2 and CO 2 gases in the low pressure range. Compounds II′ and III′ are classified among the materials for which the dehumidification and the humidification trigger points are the same or too close (10% relative humidity (r.H.) in their case), while I′ shows a good potential to be used for automatic indoor control in the range of 15−25% r.H. recommended for many activities. All the differences observed in the water sorption properties of the three materials are related to (i) the type of water cluster which is built in each material, (ii) the strength of the hydrogen bonds within each water cluster and between the clusters and its host, and (iii) the strength of the intrahost interactions which keep the pores of the material closed.

The amino group in the MOF NH 2 -MIL-101(Cr) was postsynthetically converted into urea-groups partially using either ethyl isocyanatoacetate, furfuryl isocyanate, p-toluenesulfonyl isocyanate or 3-(triethoxysilyl)propyl isocyanate in acetonitrile. The derived four novel urea-MOFs exhibit the expected lower BET surface areas and pore volumes than MIL-101(Cr) and NH 2 -MIL-101(Cr) MOFs but the partially p-toluenesulfonyl-ureamodified MOF exhibits an outstanding SO 2 adsorption capacity of 823 cm 3 g À 1 (corresponding to 36.7 mmol g À 1 or 70 wt.% at T = 0°C and 0.9 bar), which is the second highest SO 2 uptake of any known material today -surprisingly even better than for highly porous MIL-101(Cr) with an uptake of 645 cm 3 g À 1 SO 2 under the same conditions. The high uptake is linked to the favorable dipole interactions of SO 2 with the sulfonyl group of the p-toluenesulfonyl-modified MOF.