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In this study, Cu/Zn/Al2O3-AC (AC = activated carbon) catalyst was synthesized and evaluated for dimethoxymethane (DMM) reformation to hydrogen. The Cu/Zn/Al2O3-AC catalyst was prepared using high surface area metal organic frameworks (MOFs) consisting of Cu3(BTC)2 (MOF-199) and Zn4O(BDC)3 (MOF-5) for Cu(II) and Zn(II) sources respectively, as precursors while γ-Al2O3 was applied as support. The synthesized catalyst was investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), Temperature programmed desorption (NH3-TPD) and Energy-dispersive X-ray spectroscopy (EDX) techniques. Complete DMM conversion was observed over Cu/Zn/Al2O3-AC catalyst (Cu:Zn:Al mole ratio of 6:3:2) under atmospheric pressure, T = 533 K, GHSV = 20 NL h−1 gcat−1, N2/H2O/DMM = 24/5/1 volume percent (vol%) with hydrogen productivity of 12.8 L H2 h−1 gcat−1 and 64% hydrogen concentration. Application of MOFs as precursors and modified activated carbon as an acidic component provided the catalyst with the porous structure and high specific surface area for the hydrolysis of DMM, subsequently, high selectivity and productivity of hydrogen was obtained. [ABSTRACT FROM AUTHOR]

In the present study nano-sized strontium-doped lanthanum manganite, LaSrMnO (LSM), were synthesized by three simple different methods (a) co-precipitation, (b) ultrasonic and (c) microwave-assisted co-precipitation. A lanthanum(III) coordination polymer, [pyda.H][La(pydc)(HO)]·2HO, where [pyda.H] = 2,6-diaminopyridinium, and (pydc) = 2,6-pyridinedicarboxylate, was used as a new precursor. The products were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), thermal gravimetric (TG) and differential thermal analyses (DTA), as well as by Energy-dispersive X-ray spectroscopy (EDX). The XRD results showed that the crystal lattice of the product obtained was orthorhombic perovskite structure. The porosity, particle size and homogeneity of calcinated LSM were strongly dependent on the preparation method. In addition, the results proved that the product formation time was decreased considerably when ultrasonic or microwave irradiation methods were used. [ABSTRACT FROM AUTHOR]

A new nano-sized La(III) supramolecular compound, [pyda.H][La(pydc)(HO)]·2HO ( 1), where [pyda.H] = 2,6-diaminopyridinium, and [pydc] = 2,6-pyridinedicarboxylate, was synthesized by the sonochemical method and characterized by field emission scanning electron microscope (FESEM), X-ray powder diffraction (XRD) and elemental analyses. Lanthanum oxide nanoparticles were prepared by direct thermal decomposition of 1 nanostructures in a programmable furnace up to 800 °C in ambient atmosphere. The structural characterization was performed by powder XRD; and, morphological observations by FESEM revealed that the quasi-spherical LaO nanoparticles obtained are well crystallized and uniform in both morphology and particle size. The study demonstrates that supramolecular compounds may be suitable precursors for the simple one-pot preparation of nanoscale metal oxide materials with different morphologies. [ABSTRACT FROM AUTHOR]

A new lead(II) coordination polymer, [PbBr(CHNO)] ( 1), where CHNO is (2,4-diamino-6-piperidine-1-yl) pyrimidine N-oxide (minoxidil) is synthesized and characterized. Polymer 1 is synthesized in methanol by sonochemical and hydrothermal methods from lead(II) acetate, KBr and the minoxidil ligand. The crystal structure of [PbBr(CHNO)] indicates a syndiotactic coordination polymer. The Pb(II) atom lies on a mirror plane; the mirror plane is perpendicular to the pyrimidine ring bisecting the piperidine ring. N-H···O intramolecular and C-H···Br, N-H···N strong intermolecular interactions were observed. Micro-rods of PbO and nano-plates of PbOHBr were prepared by thermal decomposition of the nano-structured [PbBr(CHNO)] as a precursor. Characterization of the products was carried out using X-ray crystallography, elemental analysis, FTIR spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and thermal analysis. The sonochemical method resulted in a significant reduction of reaction time, reaction temperature and particle sizes of the products. [ABSTRACT FROM AUTHOR]