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A one-step hydrothermal synthesis with small amines and 1,3,5-benzenetriphosphonic acid was used to prepare single crystals of i s o s t r u c t u r a l a n i o n i c m e t a l − o r g a n i c f r a m e w o r k s ( M O F ) : Z n 2 . 5 ( H ) 0 . 4 − 0 . 5 ( C 6 H 3 O 9 P 3 ) ( H 2 O ) 1 . 9 − 2 ( N H 4 ) 0 . 5 − 0 . 6 a n d Zn 2.5 (H) 0.75 (C 6 H 3 O 9 P 3 )(H 2 O) 2 (CH 3 NH 3 ) 0.25 . The ammonium ions are exchangeable with lithium ions. The MOF exhibits reversible dehydration, and the process was studied by two complementary methods: solid state NMR and in situ X-ray diffraction. These experiments revealed three different phases. The crystal structures of all phases have been determined, showing loss in volume of the structure due to a phase change. The ammonium ions remain in the structure and are forced to occupy the larger pores due to a reduction in free volume. The change in positions of the guest molecules in the framework has an effect on the potential conductivity properties of the materials. Changes in framework and guest molecules due to negative expansion have an effect on other physical and chemical properties and need to be explored.

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We report on attempts to synthesize Mo nanoparticles under reducing conditions in ionic liquids (ILs). Ionic liquids were based on the 1-ethyl-3-methylimidazolium or 1-butyl-3-methylimidazolium (Emim and Bmim, resp.) cations and the dicyanamide N(CN)2, triflate (OTf), bis(trifluoromethylsulfonyl)imide-(NTf2), tetrafluoroborate (BF4), ethyl sulfate (ES), and methylsulfonate (MS) anions. (NH4)6Mo7O24∗4H2O and NaBH4 were reacted in a set of imidazolium ionic liquids (ILs) at 180°C to evaluate the potential of the ILs for stabilization of metallic Mo nanoparticles. XRD and TEM reveal a strong influence of the IL anion on the particle sizes, shapes, and crystal structures. The influence of the IL cation and the reaction temperature is much less pronounced.

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A coordination polymer with the composition C 12 H 20 O 16 Zn 2 (ZnBTC) (BTC = benzene-1,3,5-tricarboxylate) was synthesized under hydrothermal conditions at 120 °C, and its crystal structure was determined using single-crystal X-ray crystallography. Firstprinciples electronic structure investigation of the compound was carried out using the density functional theory computational approach. The highest occupied molecular orbital, the lowest unoccupied molecular orbital, the energy gap, and the global reactivity descriptors of ZnBTC were investigated in both the gas phase and the solvent phase using the implicit solvation model, while the donor−acceptor interactions were studied using natural bond orbital analyses. The results revealed that ZnBTC is more stable but less reactive in solvent medium. The larger stabilization energy E (2) indicates a greater interaction of ZnBTC in the solvent than in the gas phase. Orange peel activated carbon and banana peel activated carbon chemically treated with ZnCl 2 and/or KOH were used to modify the synthesis of ZnBTC to obtain nanocomposites. ZnBTC and the nanocomposites were characterized by powder Xray diffraction (PXRD), thermogravimetric analysis, and Fourier transform infrared. The specific surface area (S BET ) and the average pore diameter of the materials were determined by nitrogen sorption measurements using the Brunauer−Emmett−Teller (BET) method, while scanning electron microscopy and transmission electron microscopy were used to observe their morphology and particle size, respectively. The PXRD of all the activated carbon materials exhibited peaks at 2θ values of 12.7 and 13.9°corresponding to a d-spacing of 6.94 and 6.32 Å, respectively. The N 2 adsorption−desorption isotherm of the materials are of type II with nanocomposites showing enhanced S BET compared to the pristine ZnBTC. The results also revealed that activated carbons from the banana peel and the derived nanocomposites exhibited better porous structure parameters than those obtained from orange peel. The degradation efficiency of methyl orange in aqueous solutions using ZnBTC as a photocatalyst was found to be 52 %, while that of the nanocomposites were enhanced up to 79 %.

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