The 3D metal-organic framework (MOF) (3)(infinity){[Ni(3)(mu(3)-btc)(2)(mu(4)-btre)(2)(mu-H(2)O)(2)]. approximately 22H(2)O} is found to be a reversibly dehydratable-hydratable water-stable MOF material with a large loading spread of 210 g/kg as a candidate for solid adsorbents in heat transformation cycles for refrigeration, heat pumping, and heat storage.

The hydrothermal reaction of M(NO3)2.6H2O (M = Ni and Zn) with benzene-1,3,5-tricarboxylic acid (H3btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers (MOFs) 3 infinity{[Ni3(mu3-btc)2(mu(4)-btre)2(mu-H2O)2]. approximately 22H2O} (1) and 3 infinity{[Zn3(mu4-btc)2(mu4-btre)(H2O)2].2H2O} (3). The compounds, characterized by single-crystal X-ray diffraction, X-ray powder diffraction and thermoanalysis feature trinuclear secondary building units (SBU) within the three-dimensional frameworks. The trinuclear nickel unit in 1 exhibits an intra-trimer together with some weak inter-trimer antiferromagnetic coupling with J = -13.88(8) cm(-1) from the magnetic susceptibility measurement between 1.9-300 K. The zinc coordination polymer 3 shows a strong fluorescence at 423 nm upon excitation at 323 nm (not seen in the free btre ligand). Compound 3 is thermally robust until 200 degrees C (ambient pressure) where loss of the water molecules starts. Careful control of the dehydration procedure (freeze-drying) for 1 and (heating to 280 degrees C) for allowed for a solid-state reaction with single-crystal-to-single-crystal structural transformations in obtaining the largely dehydrated products 3 infinity{[Ni3(mu2-btc)2(mu4-btre)2(mu-H2O)2(H2O)2].4H2O} (2) and 3 infinity{[Zn3(mu6-btc)2(mu4-btre)2]. approximately 0.67H2O} (4), respectively. In the transformation from 1 to 2 the unit cell volume is reduced to about 60%. The transition from 3 to 4 involves breakage and formation of new Zn-O bonds.

Hydrothermal reactions of 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) with copper(II), zinc(II), and cadmium(II) salts have yielded the dinuclear complexes [Zn2Cl4(mu2-btre)2] (1) and [Zn2Br4(mu2-btre)2] (2), the one-dimensional coordination polymer infinity1[Zn(NCS)2(2-btre)] (3), the two-dimensional networks infinity2[Cu2(mu2-Cl)2(mu4-btre)] (4), infinity2[Cu2(mu2-Br)2(mu4-btre)] (5), and infinity2{[Cd6(mu3-OH)2(mu3-SO4)4(mu4-btre)3(H2O)6](SO4).6H2O} (6), and the three-dimensional frameworks infinity3{[Cu(mu4-btre)]ClO4.0.25H2O} (7), 3{[Zn(mu4-btre)(mu2-btre)](ClO4)2} (8), infinity3{[Cd(mu4-btre)(mu2-btre)](ClO4)2} (9), and infinity3[Cu2(mu2-CN)2(mu4-btre)] (10, 2-fold 3D interpenetrated framework). The copper-containing products 4, 5, 7, and 10 contain the metal in the +1 oxidation state, from a simultaneous redox and self-assembly reaction of the Cu(II) starting materials. The cyanide-containing framework 10 has captured the CN- ions from the oxidative btre decomposition. The perchlorate frameworks 7, 8, or 9 react in an aqueous NH4+PF6- solution with formation of the related PF6--containing frameworks. The differences in the metal-btre bridging mode (mu2-kappaN1:N1', mu2-kappaN1:N2 or mu4-kappaN1:N2:N1':N2') and the btre ligand symmetry can be correlated with different signal patterns in the 13C cross polarization magic angle spinning (CPMAS) NMR spectra. Compounds 2, 4, 5 and 7 to 10 exhibit fluorescence at 403-481 nm upon excitation at 270-373 nm which is not seen in the free btre ligand.

The hydrothermal reaction of M(NO(3))(2).4H(2)O (M = Zn and Cd) with benzene-1,4-dicarboxylic acid (H(2)bdc) or benzene-1,3-dicarboxylic acid (H(2)ip) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers (MOFs) {[Zn(2)(micro(2)-bdc)(2)(micro(4)-btre)]} (), {[Cd(2)(micro(4)-bdc)(micro(4)-btre)(2)](NO(3))(2).H(2)O} and {[Zn(2)(micro(3)-ip)(2)(micro(2)-btre)(H(2)O)(2)].2H(2)O} (). The compounds, characterized by single-crystal X-ray diffraction, X-ray powder diffraction, solid-state cross-polarization (CP) magic-angle-spinning (MAS) (13)C NMR and thermoanalysis, feature 3D metal-organic frameworks for and and 2D double layers which are connected through hydrogen bonds from the aqua ligands for 3. The CPMAS (13)C NMR spectra picture the symmetry-independent (unique) C atoms and the bdc/ip-to-btre ligand ratio in agreement with the crystal structures. The zinc and cadmium coordination polymers show a strong bluish fluorescence upon excitation with UV light (the free btre ligand is non-luminescent).

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Various solid Cu-containing catalysts were prepared. Their performance in the selective catalytic reduction of NO x using propene as reducing agent from 150 to 450 °C in an O 2 -rich model exhaust gas in the presence of water vapor was investigated. This research aimed at the development of a catalytic NO x to N 2 (DeNO x ) step to be part of a ship diesel exhaust abatement system in combination with other techniques, such as nonthermal plasma. Among the catalysts tested, Cu on zeolite Y with an optimized load of 16 wt % (denoted as 16Cu/Y) displayed excellent DeNO x activity with highest selectivity toward N 2 at 290 °C. The influence of other variables, such as Cu load, calcination temperature, feed composition, and GHSV on the performance of 16Cu/Y was studied, as well. The highest N 2 yield of 98% was achieved using 2000 ppm of propene in the gas feed. The presence of O 2 proved to be a crucial factor for promoting the selective reduction of NO x with C 3 H 6 over this catalyst. On the other hand, the presence of water in the feed decreased NO x to N 2 conversion. However, the catalyst showed excellent stability over 120 h, even at high water concentration, and also after repeated heating from ambient temperature to 450 °C, and it was reusable after downtimes without remarkable loss in activity. The nature of the Cu species was studied by XPS, XRD, and TPR experiments.

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