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Fischer-Tropsch synthesis (FTS), an important process for the production of liquid fuels and chemicals from syngas derived from coal and biomass, is receiving renewed interest for both industrial and academic applications. Adjusting the product distribution of hydrocarbons is the focus of research in this field. Herein, a novel carbon-encapsulated Fe3O4 nanocatalyst was synthesized by a simple one-step solvothermal method without calcination. The catalyst exhibited excellent catalytic activity and higher selectivity for C5-12 hydrocarbons (gasoline range products) than the traditional Fe2O3 catalyst. A 45.25 % C5-12 selectivity was obtained for Fe3O4@C, which is close to the maximum value from the Anderson-Schulz-Flory distribution. [ABSTRACT FROM AUTHOR]

Two compounds based on polyoxometalates, (4,4'-H2bpy)7(4,4'-Hbpy)[ [image omitted]]2[ [image omitted]] ·10H2O (1) and (4,4'-H2bpy)6(4,4'-bpy)[ [image omitted]]2 · 18H2O (2), have been prepared under hydrothermal conditions and characterized by IR, XPS spectra, TG analyses, and single crystal X-ray diffraction. Both compounds consist of 4,4'-bipyridine units and polyoxometalates: [ [image omitted]]5- for 1 and [ [image omitted]]6- for 2. In addition, 1 contains both Keggin-type and disordered Keggin-type anions, while 2 contains a (H2O)10 water cluster. [ABSTRACT FROM AUTHOR]

The new polyoxometalate double-supporting transition metal complexes, {[Co(phen) 2 ] 2 C 2 O 4 } {H 2 P O 44 [Co(phen) 2 H 2 O] 2 }·7H 2 O (1) (phen  =  1,10-phenanthroline) have been hydrothermally synthesized and characterized by single crystal X-ray analysis, IR, XPS, ESR and elemental analysis. Compound 1 is composed of a highly reduced tetra-capped pseudo-Keggin polyoxoanion supporting two transition metal complexes, a binuclear cobalt complex cation and lattice water. The magnetism and third-order non-linear optical properties of 1 have also been studied. [ABSTRACT FROM AUTHOR]

Abstract: Four new supramolecular architectures based on Keggin polyoxometalates (POMs): [(HSiMo12O40)(H4,4′-bpy)2][(H4,4′-bpy)(H2O)2]·2H2O (1), [(HSiW12O40)(H4,4′-bpy)2][(H4,4′-bpy)(H2O)2]·2H2O (2), [(SiW12O40)(H4,4′-bpy)4]·(4,4′-bpy)·2H2O (3) and [H4SiW12O40](2,2′-bpy)4 (4) (bpy=bipyridine) have been prepared hydrothermally and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses, fluorescence analysis and single crystal X-ray diffraction analyses. Both compounds 1 and 2 exhibit supramolecular 2D layer structures. Compound 3 exhibits a novel supramolecular double chain structure. Compound 4 contains a 1D chain structure with two 2,2′-bpy ligands as double bridges. It should be noted that compound 4 is the first example of hybrid compound based on 2,2′-bpy ligands and POMs. [Copyright &y& Elsevier]

Abstract: Four new organic–inorganic hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}: [H24,4′-bpy][PMo12Sb2O40]·6H2O (1), [Him]2[PMo12Sb2O40]·H2O (2), [H3(DABCO)2][PMo12Sb2O40]·2H2O (3) and [Mn(phen)3][PMo12Sb2O40] (4) (bpy=bipyridine, im=imidazole, DABCO=1,4-diazabicyclo[2,2,2]octane, phen=phenanthroline) have been prepared hydrothermally and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses, fluorescence analysis and single crystal X-ray diffraction analyses. The four compounds are new examples of hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}. Compound 1, 2 and 3 are constructed from {PMo12Sb2O40} anions and different organic moieties, respectively. Compound 4 is formed by combining {PMo12Sb2O40} anions and manganese coordination complexes. [Copyright &y& Elsevier]

Abstract: Two new hybrid compounds based on Keggin-type polyoxometalates: {[PMo12O40][Ni(Phen)2(H2O)]2}·K·2OH− (1) and [Cd2(Phen)4Cl2][HPW12O40]·H2O (2) (Phen=1,10-phenanthroline), have been prepared and characterized by IR, UV–vis, XPS, XRD and single crystal X-ray diffraction analyses. Compound 1 exhibits a 1-D chain structure constructed from Pseudo-Keggin polyoxometalate bi-supported transition metal coordination complexes linked by K+ ions. Compound 2 contains Pseudo-Keggin polyoxoanions [HPW12O40]2− and novel metal–chloride–ligand coordination complexes [Cd2(Phen)4Cl2]2+. [Copyright &y& Elsevier]

Abstract: Three new supramolecular compounds based on triethylenediamine and different polyoxometalates [WVI 3VV 3O19H]{[Cu(HDABCO)]2(H2O)} (1), [P2MoVI 18O62][HDABCO]2[H2DABCO]2·12H2O (2) and [MoVI 7.5WVI 0.5O27][Cu(HDABCO)]2·2H3O·2H2O (3) (DABCO=triethylenediamine) have been synthesized hydrothermally and characterized by IR, TG, XPS and X-ray diffraction analyses. Crystal structure analyses reveal that compound 1 exhibits a face-centered cubic packing motif, compound 2 displays a supramolecular structure constructed form the “chains” arranged hexagonally, compound 3 contains [Mo7.5W0.5O27]∞ chain decorated by [Cu(HDABCO)]2+ cations, which was then packed into a layer structure. These results show that the same organonitrogen combining with the different POMs will yield different supramolecular networks. [ABSTRACT FROM AUTHOR]

Abstract: A new compound [Mo8V7O42][Cu(2,2′-bpy)2]2[Cu(2,2′-bpy)]·2H3O (1) has been synthesized under hydrothermal conditions and characterized by IR, UV–vis spectrum, elemental analysis, XRD, ESR, XPS, X-ray diffraction analysis and magnetic property study. Single-crystal X-ray structure analysis indicates that the compound 1 is a novel Keggin polyoxoanion tri-supported mixed-valent transition metal coordination complex. [ABSTRACT FROM AUTHOR]

Abstract: Two new supramolecular compounds based on tungsten–vanadium polyoxoanions formulated as [Cu(2,2′-bipy)3]2H14[PW2.2V9.8O40(VO)2[Cu(2,2′-bipy)2H2O]2][PW2.2V9.8O40(VO)2]·10H2O (1) and [Cu4(2,2′-bipy)4(H2O)2(PO4)2]H6.5[PW8.4V3.6O40]·2H2O (2) (2,2′-bipy=2,2′-bipyridine) have been synthesized hydrothermally and characterized by IR, TG, XPS and X-ray diffraction analyses. Crystal structure analyses reveal that compounds 1 and 2 exhibit novel 2D supramolecular layer structures constructed from tungsten–vanadium polyoxoanions and different types of secondary building units (SBUs), respectively, the different SBUs are formed by [Cu(2,2′-bipy)2H2O]2+ and [Cu(2,2′-bipy)3]2+ cations in compound 1 and [Cu4(2,2′-bipy)4(H2O)2(PO4)2]2+ cations in 2, respectively. Study of magnetic properties indicated the presence of antiferromagnetic behaviors for both compound 1 and 2. [Copyright &y& Elsevier]

Abstract: Two new molybdenum–vanadium polyoxometalate tri-supported transition metal complexes [Cu(2,2′-bipy)] [Cu(2,2′-bipy)2]2[PMo8V6O42]·nH2O (n =1.5 (1) and n =2 (2); 2,2′-bipy=2,2′-bipyridine) have been hydrothermally synthesized and characterized by elemental analyses, IR, XPS and single-crystal X-ray diffraction analyses. Both compound 1 and compound 2 contain molybdenum–vanadium polyoxometalates, each of which support one [Cu(2,2′-bipy)]2+ cation and two [Cu(2,2′-bipy)2]2+ cations, respectively. The difference between compound 1 and compound 2 is that the polyoxoanion of 1 is a bi-capped α-Keggin cluster and that of 2 is a bi-capped pseudo-Keggin one. Studies of magnetic properties indicated the presence of ferromagnetic behaviors for compounds 1 and 2. [Copyright &y& Elsevier]

Abstract: A novel polyoxometalate {[Ni(enMe)2]2[Ni(enMe)2(H2O)]2[As2W18Ni4(enMe)2O68]}·2H3O·2H2O (1) (enMe=1,2-propylenediamine) has been synthesized and characterized, which is the first high-dimensional structure constructed from sandwich-type transition metal substituted tungstates and transition metal coordination groups. [Copyright &y& Elsevier]

Abstract: A novel polyoxometalate [Cu(phen)2]3{PW4 VIW5 VV3 IVO40(VIVO)3[Cu(en)2]}⋅4H2O 1 (en=ethylenediamine, phen=1,10-phenanthroline) has been synthesized hydrothermally and characterized by elemental analysis, IR, XPS, TG, EPR and single-crystal X-ray diffraction analysis. The crystal structure analysis shows that compound 1 contains a novel highly reduced tri-capped and mono-supported pseudo-Keggin-type heteropolyanion, {PW4 VIW5 VV3 IVO40(VIVO)3[Cu(en)2]}6−, three [Cu(phen)2]2+ cations and four lattice water molecules. They are further linked to form three-dimensional supramolecular networks through extensive hydrogen bonding and π–π stacking interactions. Interestingly, the water dimer and terminal oxygen of the cluster polyanion constitute a beautiful supramolecular helix chain. The heteropolyanion is the first example of tri-capped and mono-supported pseudo-Keggin-type tungstovanadophosphate and the pH value is crucial for obtaining compound 1 in synthetic procedure. [Copyright &y& Elsevier]

Abstract: Six new complexes constructed by 5-sulfosalicylic acid and bipyridyl-like ligands (2,2′-bipy and 1,10-phen), namely [Cu4(OH)2(ssal)2(phen)4 ·7H2O] (1), [Cu4(OH)2(ssal)2(bipy)4 ·2H2O] (2), [Cd(Hssal)(bipy)] (3), [Cd(HL)2(phen)2] (4), [Cr(ssal)(bipy)(H2O)2 ·2H2O] (5) and [Cr(ssal)(phen)2] (6) (H3ssal=5-sulfosalicylic acid, H2L= p-hydroxybenzenesulfonic acid, bipy=2,2′-bipy, phen=1,10-phen) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. Complexes 1 and 2 are both tetranuclear copper complexes with a stepped topology. In complex 3, a new coordination mode of the Hssal2− group is reported in this work. During the synthetic process of complex 4, in situ decarboxylation of 5-sulfosalicylic acid into p-hydroxybenzenesulfonic acid is involved. Two chromium 5-sulfosalicylates (5 and 6) are reported for the first time. These new complexes display different supramolecular structures by O–H⋯O, C–H⋯O hydrogen bonds as well as π⋯π, C–H⋯π and O⋯π interactions. The results of magnetic determination show that ferromagnetic interactions exist in complex 1, however, antiferromagnetic interactions exist in 2. [Copyright &y& Elsevier]

Abstract: Three new molybdophosphates, [Co(dien)2]·(H3dien)6·{[CoMo12O24(OH)6(HPO4)2(PO4)6][Co(Hdien)]2[CoMo12O24(OH)6(PO4)8]}·(dien)·4H3O·5H2O (1), (H3dien)4[MMo12O24(OH)6(HPO4)4(PO4)4]·10H2O [M=Co for (2), Ni for (3); dien=diethylenetriamine], have been synthesized by employing hydrothermal method and characterized by single crystal X-ray diffraction. Compound 1 is built up of Co[P4Mo6]2 units as the structural motif covalently linked by [Co(Hdien)] complex subunits to yield an unusual 1-D chain. Compounds 2 and 3 are isomorphic and both display covalent discrete M[P4Mo6]2 cluster structures which are linked by the hydrogen bonds to form 3-D supramolecular networks. Both 1 and 2 display antiferromagnetic interaction and these three compounds all exhibit intensive photoluminescence. [Copyright &y& Elsevier]

Abstract: Two novel organic–inorganic hybrid compounds based on organoamines and polyoxovanadates formulated as (H2dien)4[H10V18O42(PO4)](PO4)·2H2O (1) (dien=diethylenetriamine) and (Him)8[HV18O42(PO4)] (2) (im=imidazole) have been prepared under hydrothermal conditions by using different starting materials, and characterized by elemental analyses, IR, ESR, XPS, TGA and single-crystal X-ray diffraction analyses. Crystal data for compound 1: C16H74N12O52V18P2, Monoclinic, space group C2/c, a=23.9593(4)Å, b=13.0098(2)Å, c=20.1703(4)Å, β=105.566(3)°, V=6056.6(19)Å3, Z=4; for compound 2, C24H41N16O46V18P, Tetragonal, space group I4/mmm, a=13.5154(8)Å, b=13.5154(8)Å, c=19.1136Å, β=90°, V=3491.4(3)Å3, Z=2. Compound 1 consists of protonated diens together with polyoxovanadates [H10V18O42(PO4)]5−. Compound 2 is composed of protonated ims and polyoxovanadates [HV18O42(PO4)]8−. There are hydrogen-bonding interactions between polyoxovanadates and different organoamines in 1 and 2. Polyoxovanadates are linked through H2dien into a three-dimensional network via hydrogen bonds in 1, while polyoxovanadates are linked by Him into a two-dimensional layer network via hydrogen bonds in 2. The crystal packing patterns of the two compounds reveal various supramolecular frameworks. [Copyright &y& Elsevier]

Abstract: A new 3D supramolecular framework, (1) (en=ethylenediamine), has been hydrothermally synthesized and characterized by elemental analysis, IR, XPS, TG and single crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group C2/c, a =12.735(3), b =26.976(5), c =21.171(4)Å, β =92.64(3)°, V =7265(2)Å3, and Z =4. Complex 1 exhibits an interesting three-dimensional supramolecular framework assembled by sinusoidal-like arrangement of two-dimensional coordination polymer layers and crystal water molecules. The magnetic behavior of 1 has also been studied. [Copyright &y& Elsevier]

Abstract: Three compounds based on polyoxometalate building blocks, [Cu(en)2]{[Cu(en)2]2[MoVI 5MoV 3VIV 8O40(PO4)]}·4H2O (1), [Co(en)2]{[Co(en)2]2[HMoVI 4MoV 4VIV 8O40(PO4)]}·5H2O (2) and [Ni(en)2]{[Ni(en)2]2[MoVI 5MoV 3VIV 8O40(VO4)]}·2H2O (3) (en=ethylenediamine), have been synthesized and characterized by elemental analysis, IR, XPS, XRD, TGA and single-crystal X-ray diffraction analysis. The result of structure determination shows that isomorphic compounds 1, 2 and 3 feature a one-dimensional chain built from the reduced tetra-capped pseudo-Keggin polyoxoanion, which is further interconnected by [M(en)2]2+ (M=Cu, Co and Ni) groups via the terminal oxygen atoms of polyoxoanions. The crystal data for these compounds are the following: 1, monoclinic, space group C2/c, a =26.702(3)Å, b =13.4539(14)Å, c =19.5987(19)Å, β =108.650(2)°, V =6671.0(12)Å3, Z =4; 2, monoclinic, space group C2/c, a =26.244(3)Å, b =13.5070(17)Å, c =19.581(3)Å, β =106.881(2)°, V =6641.8(15)Å3, Z =4; 3, monoclinic, space group C2/c, a =26.2789(15)Å, b =13.5408(6)Å, c =19.6312(9)Å, β =106.2590(10)°, V =6706.1(6)Å3, Z =4. Variable-temperature magnetic susceptibility measurements of compounds 1 and 3 reveal the feature of antiferromagnetic exchange in these compounds. [Copyright &y& Elsevier]

Abstract: A novel polyoxometalate (1) has been synthesized in the system of Sb2O3-(NH4)6Mo7O24 ·4H2O-H3PO4-en-H2O under hydrothermal conditions and characterized by IR, TGA, elemental analyses, single crystal X-ray diffraction and XPS. Interestingly, compound 1 displays three-dimensional network consisting of one-dimensional sinusoidal chain [(Hen)2(H2O)2]2+ and two-dimensional layer formed by . The structure unit is the first example of bicapped by antimony α-Keggin structure. [Copyright &y& Elsevier]

The novel polyoxovanadate containing antimony [(C2N2H10)2β-{SbIII8VIV14O42(H2O)}](C2N2H8) · 4H2O has been synthesized from a mixture of VOSO4, Sb2O3, en and H2O under hydrothermal conditions. The spherical [β-{SbIII8VIV14O42(H2O)}]4− clusters form a one-dimensional double-chain structure with non-bonding Sb ⋯ O contacts. [Copyright &y& Elsevier]

The title compound [NiII(phen)3]2[Cu10H2I16] 1 (phen=1,10-phenanthroline, C12H8N2) was hydrothermally synthesized from a simple reaction of CuI–NiCl2·6H2O–phen·H2O–H2O. X-ray analysis revealed that it consists of NiN62+ core cation and decanuclear iodocuprate(I) anion together with two dissociative H+ ions. In anionic unit, the discrete decanuclear iodocuprate(I) is formed by crystallographically independent five monovalent copper atoms and eight iodine atoms via an inversion center. There exist two types of Cu(I) coordination sites; only one copper(I) atom is in a highly distorted triangular planar site, and the other four copper(I) atoms display the tetrahedral geometries. It deserves to be noted that four types of bridging modes of I− ions in which two are ordinary μ2- and μ3-bonding modes can be found. But the other two are the rectangle planar geometry and the novel μ4-bridge like an “umbrella”, and both of them are rather rare in the halocuprates(I). Compound 1 was crystallized in triclinic space group P1¯ with a=11.6861(17), b=14.590(2), c=14.649(2) A˚, α=76.370(2), β=70.830(2), γ=81.320(3)o, R=0.075, and was characterized by elemental analysis, IR spectrum and UV-VIS spectrum. The third-order non-linear optical property of 1 was also investigated and the compound exhibits the reverse saturable absorption and self-defocusing performance. [Copyright &y& Elsevier]

A novel one-dimensional chain coordination polymer [Cu6(CN)6(phen)4]n 1 was synthesized from the simple hydrothermal reaction of Cu(CH3COO)2·H2O, K3[Fe(CN)6] and phen·H2O. With phen, CuCN exhibits a novel B–C–B–C chain array, namely the infinite chain is propagated via alternately three-coordinate (B) and four-coordinate (C) sites of monovalent Cu ions. It should also be noticed that the compound is the first example where the parent chain not only exhibits the [Cu(phen)]+ side arm, but also is directly bound to the chelate ligand. Moreover, the third-order non-linear optical property of compound 1 was also investigated and it shows the reverse saturable absorption and self-focusing performance. [Copyright &y& Elsevier]

A three-dimensional supramolecular compound [Ni(IN)2(H2O)4] 1 has been rationally designed and synthesized by hydrothermal method, and the structure was characterized with elemental analysis, FT–IR spectrum and X-ray diffractometer. In the packing structure, the stronger intermolecular O–H⋯O hydrogen-bonded and π–π stacking interactions are the most significant factors of controlling the novel supramolecular sheet fashion for the title compound. The third-order non-linear optical property of compound 1 was also investigated, and it exhibits nicer reverse saturable absorption and self-focusing performance. [Copyright &y& Elsevier]

The complexes [Co(Him)2(μ4-bta)1/2]n 1 and {[Cu(phen)(μ4-bta)1/2]·H2O}n 2 were hydrothermally synthesized at 160°C and their structures were determined by single-crystal X-ray diffraction. Complex 1 was triclinic, space group P–1, a=7.9294(11) A˚, b=9.621(3) A˚, c=9.6461(16) A˚, α=116.772(19)°, β=96.791(13)°, γ=102.787(19)°, Z=2, V=620.3(2) A˚3, R1=0.0252 and wR2=0.0640 [I>2σ(I)]; complex 2 was monoclinic, space group P21/c, a=7.386(3) A˚, b=12.723(4) A˚, c=15.831(3) A˚, β=102.66(2)°, Z=4, V=1451.5(7) A˚3, R1=0.0389 and wR2=0.1033 [I>2σ(I)]. In both of the structures the metal ions were linked by the μ4-bridging benzene-1,2,4,5-tetracarboxylate ligands, resulting in one-dimensional double-metal chains. The synthesized products were characterized by IR spectroscopy, UV–VIS spectra, inductively coupled plasma (ICP), elemental, thermogravimetric (TGA) and magnetic analyses. [Copyright &y& Elsevier]

The new three-dimensional open-framework cobalt(II) molybdenum(VI) phosphate, (C2H9N2)4(C2H10N2)[Co3Mo4P4O28] 1, has been prepared by the reaction of sodium molybdate, phosphoric acid and ethylenediamine with Co2+ salts. The crystal data for 1 are as follows: Tetragonal, space group I4(1)/a, a=17.088(2) A˚, c=10.745(2) A˚ V=3137.7(9) A˚3, Z=4. The structure of 1 is constructed from CoMo2P tetrahedral units connected by CoO4 tetrahedra through sharing corners. The connectivity leads to the formation of intersecting channels in all three crystallographic directions, resembling an aluminosilicate zeolite, and the channels are filled with charge-compensating ethylenediamine ions. [Copyright &y& Elsevier]

A novel compound, [Cu(en)2(H2O)]4[Cu(en)2]3.5[PMoVI8VIV6O42Cu(en)(1,10′-phen)]3·14H2O 1 (en = ethylenediamine, phen = phenanthroline), was synthesized hydrothermally (170 °C, 10 days, autogeneous pressure) and characterized by IR, ESR, elemental analyses and X-ray crystallography. The results of structure determination show that compound 1 contains three different structure cluster anions [PMoVI8VIV6O42]7− supporting complex cation [Cu(en)(1,10′-phen)]2+, in which one cluster anion possesses typical bicapped Keggin structure, while other two polyanions only have bicapped quasi-Keggin structures, and [Cu(en)(1,10′-phen)]2+ is linked through oxygen atoms to different V positions of two bicapped quasi-Keggin units. [Copyright &y& Elsevier]

By hydrothermal method, a novel supramolecular compound, Co(NIA)2(H2O)4 was synthesized and its structure was characterized with elemental analysis, FT-IR spectrum, TGA and X-ray diffractometer, indicating that it is a novel polyporous supramolecule with molecular ladder hydrogen-bonded chains. TGA curve shows its thermal stability up to 520 °C. [Copyright &y& Elsevier]

The title compound [CuBr(IN)]n 1 was hydrothermally synthesized from a simple reaction of CuBr2–IN–KBr–NaOH–H2O. X-ray analysis revealed that it is a new example containing extended one-dimensional staircase chain in copper(I) halide family. Its structure can be better described as a three-dimensional supramolecular network assembled via a combination of coordinate–covalent bonds and intermolecular hydrogen bonds. Moreover, compound 1 was characterized by elemental analysis, IR spectrum and TGA analysis. [Copyright &y& Elsevier]

Abstract: A novel polyoxometalate [PW11O39Ni(4,4′-Hbpy)]·(4,4′-H2bpy)2·3H2O (1) has been hydrothermally synthesized and characterized by IR, XPS, TG, elemental analysis and single-crystal X-ray diffraction analysis. Crystal structure analysis reveals that 1 is a novel metal coordination fragment derivative of the classic Keggin polyanion. [Copyright &y& Elsevier]

Abstract: ZnO nanorods with hexagonal structures were synthesized by the hydrothermal method at different conditions. Their room-temperature emission spectra and fluorescent dynamics were studied. The ultraviolet emissions of excitons (3.2eV) and visible emissions (2.0eV) from deep levels (DLs) of defects were observed. The results demonstrate that preparation condition pH influences the intensity ratio of the exciton emissions and DLs, as well as the decay time constant of DLs emissions. [Copyright &y& Elsevier]