One-step electrodeposited Ni3S2/Co9S8/NiS composite on Ni foam as high-performance electrode for supercapacitors.

Transition metal sulfides (TMSs) are considered as one of the promising electrode materials due to their fascinating redox reversibility and electronic conductivity. However, volume expansion during the charge/discharge process impedes their practical applications. The reasonable design of TMS electrode materials with unique morphology can improve the energy storage performance. Herein, we prepared the Ni3S2/Co9S8/NiS composite that is in situ grown on Ni foam (NF) via a one-step electrodeposition process. The optimized Ni3S2/Co9S8/NiS-7 shows a superhigh specific capacity of 2785.3 F g-1 at 1 A g-1 and remarkable rate capability. Furthermore, the as-assembled device displays a high energy density of 40.1 W h kg-1 at a power density of 799.3 W kg-1 and a satisfactory stability of 96.6% retention after 5000 cycles. This work provides a facile way to fabricate new TMS electrode materials for high-performance supercapacitors.

CuCoNi-S anchored CoMoO4/MoO3 forming core-shell structure for high-performance asymmetric supercapacitors.

Although the preparation of transition metal sulfides/oxides electrodes has been relatively perfected, it is still challenging to fabricate multi-component transition metal sulfides/oxides core-shell structure electrodes with excellent electrochemical performance. Herein, CoMoO4/MoO3@CuCoNi-S grown on nickel foam (NF) is first synthesized via facile hydrothermal and electrodeposition methods. The CoMoO4/MoO3@CuCoNi-S electrode presents an exceptional specific capacitance (2600.0 F g-1 at 1 A g-1) and 68.3% of its initial capacitance at 10 A g-1. Moreover, a CoMoO4/MoO3@CuCoNi-S//active carbon (AC) device is assembled for determining its electrochemical application. It reveals a high energy density of 42.1 W h kg-1 at a power density of 800.2 W kg-1, an extended voltage window of 1.6 V and excellent stability with 96.9% retention after 5000 cycles at 2 A g-1. This work offers a reference case for the development of multi-component transition metal sulfides/oxides core-shell structure composites for energy storage.

Multi-interface MoS2/Ni3S4/Mo2S3 composite as an efficient electrocatalyst for hydrogen evolution reaction over a wide pH range.

The exploitation of cost-efficiently electrocatalysts for hydrogen evolution reaction (HER) over a wide pH range remains a challenge. Herein, we prepared a novel multi-interface MoS2/Ni3S4/Mo2S3 composite on carbon cloth (CC) that acts as an efficient electrocatalyst over a wide pH range through a facile one-pot strategy, where (NH4)4[NiH6Mo6O24]·5H2O (abbreviated to NiMo6) as a bimetallic precursor and Ni(NO3)2·6H2O as one of the raw materials and salt are used together with thiourea (TU) for converting them into the MoS2/Ni3S4/Mo2S3 load on CC (abbreviated as MoS2/Ni3S4/Mo2S3/CC). MoS2/Ni3S4/Mo2S3/CC-24 h shows a distinguished electrocatalytic performance towards HER with long-term stability in acid and alkaline media. It presents low overpotentials of 38 mV and 51 mV in 0.5 M H2SO4 and 1.0 M KOH at 10 mA cm-2, respectively. This work can deliver a new idea to fabricate cost-efficient and long-term durability HER electrocatalysts over a broad pH range.

Single Ir atom anchored in pyrrolic-N4 doped graphene as a promising bifunctional electrocatalyst for the ORR/OER: a computational study.

The development of highly-efficient electrocatalysts with bifunctional catalytic activity for oxygen reduction reaction (ORR) and oxygen evolution reaction. (OER) still remains a great challenge for the large-scale application of renewable energy conversion and storage technologies. Herein, by means of comprehensive density functional theory (DFT) computations, we systematically explored the potential of pyrrolic-N doped graphene (pyrrolic-N4-G) supported various transition metal atoms (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Mo, Ru, Pd, W, Os, Ir, and Pt) as electrocatalysts for the ORR and OER. Our results revealed that these TM/pyrrolic-N4-G candidates exhibit high electrochemical stability due to their positive dissolution potentials. Especially, the Ir/pyrrolic-N4-G can perform as a promising bifunctional electrocatalyst for both ORR and OER with the low overpotentials (ηORR = 0.34 V and ηOER = 0.32 V). Interestingly, multiple-level descriptors, including energy descriptor (ΔGOH* - ΔGO*), (ΔGOH*), structure descriptor (φ), and d-band center (ε) can well rationalize the origin of the high catalytic activity of Ir/pyrrolic-N4-G for the ORR/OER. Our findings not only further enrich the SACs, but also open a new avenue to develop novel 2D materials-based SACs for highly efficient oxygen electrocatalysts.

Efficient and robust photocatalysts based on {P2W18} modified by an Ag complex.

Two novel Wells-Dawson polyoxometalate-based compounds, (H2bimb)2[{Ag1.5(bimb)1.5}(P2W18O62)] (1), (H2bimb)2[Ag(bimb)]0.5[Ag(eim)2]0.5[P2W18O62]·H3O (2) (bimb = 1,4-bis(imidazole-l-yl)butane, eim = ethyl(imidazole)), have been synthesized under hydrothermal conditions and characterized by IR, thermogravimetric, XRD and single-crystal X-ray diffraction analyses. In compound 1, two "U"-type bimb ligands are connected together viaπ interactions of Ag-C to form a ring unit. The ring unit alternately links with the "Z"-type bimb via an Ag-N bond to form an infinite Z-shaped {Ag4(bimb)3}n chain. The adjacent two {P2W18} clusters bonded to two Ag1 ions on two adjacent Z-shaped chains to form an inorganic dimer linker, which further joins the Z-shaped chains together, resulting in unique organic-inorganic alternating 2-D layers. Adjacent 2D layers are further aggregated together via Ag-O bonds between the Dawson cluster and the Z-type chain on different layers to yield a 3-D network with a new topology {103}2{10}{4·102}4{42·104}2. In compound 2, the eim ligand was synthesized in situ from bimb, which acts as a small molecular ligand to alter the structure and adjust the catalytic activity of compound 2. Each Ag2 connects with the bimb ligand to form a linear {Ag(bimb)} chain. Adjacent chains are bonded together via the bimb ligand to generate a supermolecule 2-D layer, in which a Dawson dimer cluster as a guest molecule is embedded in both sides of the layer through supermolecule interactions. Such 2-D layers are further supported by Ag(eim)2 units leading to 3D supermolecule nets. In addition, the compounds exhibit excellent electrocatalytic behavior and better photocatalytic degradation capability for typical dyes than other Wells-Dawson POMs.

Efficient visible light-driven water oxidation catalysts based on B-ß-{BiW8O30} and unique 14-nuclear hetero-metal sandwich unit.

A sandwich tungstobismuthate with new topology based on {B-ß-BiW8O30}-cluster and unique 14-nuclear sandwich unit is reported as a high-efficiency visible light-driven water oxidation catalyst containing extended hetero-metal oxygen layer. At optimal conditions, the turn-over number (TON) of the title compound can reach 205.5 with O2 yield of 32.88%.

Synthesis and photo-/electro-catalytic properties of a 3D POMOF material based on an interpenetrated copper coordination polymer linked by in situ dual ligands and Dawson-type phosphotungstates.

A novel 3D polyoxometalate metal organic framework (POMOF), [{CuCu (H2O)5(pzc)10(pz)6}{P2W18O62}2]·4H2O (1) (Hpzc = pyrazine-2-carboxylic acid, pz = pyrazine) has been hydrothermally synthesized and characterized by IR, TG, XRD, UV-vis and elemental analyses. In compound 1, the pzc and pz ligands are generated through in situ transformation from pyrazine-2,3-dicarboxylic acid (pzdc) to remove one or two CO2 molecules. The ligands with four coordination modes connect nine crystallographically independent Cu atoms to form a super-big circle unit. Each ring unit is connected to the adjacent six rings via an edge-sharing way to form a 2-D Cu/pz/pzc MOF layer, which is further extended along two spatial directions by two kinds of insert modes to generate an interpenetrating and staggered 3-D metal organic network. The {P2W18} clusters as nine-node inorganic guest molecules are grafted on the Cu/pz/pzc framework forming a complex 3D POMOF with a new topology {4·6·83·10}2 {4·6·8}2 {4·62·82·10}2{4·63·82}2{4·85}2{42·62·82}2{42·63·8}{43·67·813·1010·123}2 {4}6{6·82}2{62·8}2 {64·8·10}{6}2{8}4. Additionally, compound 1 exhibits good electrocatalytic activity for the reduction of H2O2 and effective photocatalytic degradation ability for three azo dyes under UV irradiation.

Two unusual 3D honeycomb networks based on Wells-Dawson arsenomolybdates with d10 transition-metal-pyrazole connectors.

Herein, two Wells -Dawson-type arsenomolybdates, formulated as [Cu(pyr)2]6[As2Mo18O62] (1) and [Ag(pyr)2]6[As2Mo18O62] (2) (pyr = pyrazole), were hydrothermally synthesized and structurally characterized via single-crystal X-ray diffraction, elemental analysis, IR and UV-vis-NIR spectroscopies, XPS, XRD, and TG analysis. The structural analysis indicated that compounds 1 and 2 were isomorphic. They are the first reported 3D honeycomb structures of Wells-Dawson-type arsenomolybdates. The [M(pyr)2] (M = Cu and Ag) connected with [As2Mo18O62]6- polyoxoanions to form the {812·123}{8}3 topological structure. The contributions of organic ligands, pH value, reaction temperature, and transition-metal (TM) to the construction of 3D networks were elucidated. Furthermore, compounds 1 and 2 exhibited fluorescence properties in the solid state at room temperature, highly efficient catalytic ability for the degradation of five organic dyes (MB, RhB, MO, AP, and CR) under UV irradiation, and obvious electrocatalytic activities for the reduction of H2O2. The mechanisms of photocatalysis and electrocatalysis have also been discussed in detail.

pH and ligand dependent assembly of Well-Dawson arsenomolybdate capped architectures.

Five Well-Dawson-type arsenomolybdates, formulated as [Cu(2,2'-bpy)2][{Cu(2,2'-bpy)}3{As2(V)Mo2(V)Mo16(VI)O62}]·4H2O (1), [H2(4,4'-bpy)]2.5[As(III)(As2(V)Mo2(V)Mo16(VI)O62)]·5H2O (2), (pyr)(imi)(Himi)3[As2(III)(As2(V)Mo3(V)Mo15(VI)O62)]·3H2O (3), [As3(III)(As2(V)Mo3(V)Mo15(VI)O62)]·4H2O (4), and (H2btp)3[As2(V)Mo18(VI)O62]·6H2O (5) (bpy = bipyridine, pyr = pyrazine, imi = imidazole, btp = 1,5-bis(triazol)pentane), have been hydrothermally synthesized and structurally characterized by the elemental analysis, TG, IR, UV-vis-NIR, XPS, XRD, and single-crystal X-ray diffraction. The structural analysis indicates that compounds 1-4 contain rare reduced Dawson {As2Mo18O62} (abbreviated as {As2Mo18}) anions as parent cluster unit, which are capped by a certain number of Cu(II) or As(III) species on different coordination positions via altering pH values and organic ligand of the reaction system. Compounds 1 and 2 are asymmetric tricopper and monoarsenate(III) capped assemble by three {Cu(bpy)}(2+) and a {AsO3} fragments, respectively. Compounds 3 and 4 are symmetric biarsenate(III) and triarsenate(III) capped cluster by four and six half occupancy {AsO3} units, respectively. Compound 5 is uncapped {As2Mo18} structures. Compounds 1-4 represent infrequent Dawson arsenomolybdate capped architectures, especially 2-4, as arsenate(III) capped Dawson-type assemblies are observed for the first time. Compounds 1-5 display good electrocatalytic activity on reduction of nitrite. Compounds 1, 2, 3, and 5 exhibit fluorescent properties in the solid state at room temperature. In addition, magnetic properties of 1-4 have been investigated in detail.

An organic-inorganic hybrid semiconductor material based on Lindqvist polyoxomolybdate and a tetra-nuclear copper complex containing two different ligands.

A 3D organic-inorganic hybrid compound based on the Lindqvist-type polyoxometalate, [{Cu(phen)}3{Cu(µ2-ox)3}{Mo6O19}] (1) (phen = 1,10-phenanthroline, ox = oxalate), has been synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR, TG, PXRD, XPS, UV-vis, and single-crystal X-ray diffraction. In compound 1, three C2O4(2-) ligands bridge one Cu atom and three Cu(phen) fragments to form a tetra-nuclear copper(II) coordination complex [{Cu(phen)}3{Cu(µ2-ox)3}](2+) unit. The six-node [Mo6O19](2-) clusters are interweaved by the 6-connected tetranuclear copper(II) complex units into an intricate 3D network structure, exhibiting a 4(12)·6(3)-nbo (sodium chloride-type) topology. Compound 1 exhibits the highest connectivity of Lindqvist-type POM hybrid materials. The electrochemical behavior of 1-CPE has been investigated in detail. Furthermore, a diffuse reflectivity spectrum of 1 reveals the presence of an optical band gap and the nature of semiconductivity with a large energy gap. A magnetic susceptibility study reveals predominant antiferromagnetic interactions between the Cu(II) bridge units.

The inhibitory effects of a new cobalt-based polyoxometalate on the growth of human cancer cells.

A new cobalt-based polyoxometalate, (Himi)2[Bi(2)W2(0)O(66)(OH)(4)Co2(H2O)(6)Na(4) (H2O)14] · 17H2O (imi = iminazole) (BWCN) has been synthesized and structurally characterized. The inhibitory activities against selected human cancer lines were also determined in this study. The cell viability and chemoresistance of BWCN on human colon carcinoma HT-29 cells were assessed by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazoliumbromide), cell morphology changes, a comet assay and western blot analysis. The typical morphologic changes of apoptosis and DNA damage indicated that BWCN could have a distinct proliferation inhibitory effect on cancer cells. BWCN as a chemotherapeutic agent also induced apoptosis on HT-29 cells and showed a significant expression of cleaved-caspase-3. These results suggested that the active site of BWCN is the polymeric anion based on the basic tectonic block {BiW(9)}, and the possible mechanism is related to the interference of DNA synthesis in cancer cells.

Novel antitumor agent, trilacunary Keggin-type tungstobismuthate, inhibits proliferation and induces apoptosis in human gastric cancer SGC-7901 cells.

A new one-dimensional chain-like compound of tungstobismuthate, [(W(OH)2)2 (Mn(H2O)3)2(Na3(H2O)14)(BiW9O33)2](Himi)2·16H2O (1) (imi = iminazole), has been synthesized in aqueous solution. The structure of 1 was identified by elemental analysis, IR, thermogravimetry (TG), X-ray photoelectron spectroscopy (XPS), (183)W-NMR, and single crystal X-ray diffraction. To investigate the inhibitory effect of 1 on human gastric adenocarcinoma SGC-7901 cells, cell proliferation and apoptosis initiation were examined by MTT assay (MTT = 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazoliumbromide), flow cytometry, nuclear staining, transmission electron microscopy, single cell gel electrophoresis, DNA fragmentation, and Western blotting. The results showed that 1 inhibited cell proliferation and induced apoptosis in SGC-7901 cells in dose-dependent manner. In addition, 1 also decreased the expression of bcl-2 protein and nuclear factor-κB p65 protein in SGC-7901 cells. And expression of bcl-2 protein exhibits a decreasing trend with increase of concentration of 1. Thus, 1 possessed a potential antitumor activity in SGC-7901 cells. This suggests that polyoxotungstates will provide a promising and novel antitumor agent in prevention and treatment of gastric adenocarcinoma.

Three new three-dimensional organic-inorganic hybrid compounds based on PMo12O40(n-) (n = 3 or 4) polyanions and Cu(I)-pyrazine/Cu(I)-pyrazine-Cl porous coordination polymers.

Three new organic-inorganic hybrid compounds based on PMo12O40(n-) (n = 3 or 4) polyanions and Cu(I)-pz/Cu(I)-pz-Cl porous coordination polymers: [Cu(I)(pz)]3[PMo(VI)12O40] (1), [Cu(I)(pz)1.5]4[PMo(V)Mo(VI)11O40]·pz·2H2O (2), [Cu(I)3(pz)3Cl][Cu(I)2(pz)3(H2O)][PMo(V)Mo(VI)11O40] (3) (pz = pyrazine) have been hydrothermally prepared and characterized by elemental analysis, IR, TG, XRD, XPS and single-crystal X-ray diffraction. Compound 1 presents a three-dimensional Cu(I)-pz framework with cube-like chambers, into which PMo(VI)12O40(3-) Keggin ions are incorporated. Compound 2 shows a three-dimensional sandwich-like framework, and PMo(V)Mo(VI)11O40(4-) polyanions are located in the octagonal voids of every two-dimensional Cu(I)-pz 4(1)8(2) network structure. Compound 3 exhibits a two-dimensional Cl-bridged Cu(I)-pz-Cl double-layer structure, and two kinds of PMo(V)Mo(VI)11O40(4-) polyanions as bridging linkers connect two adjacent double-layers to form a three-dimensional organic-inorganic framework through Cu(I)-O bonds. Additionally, their electrochemical characters, electrocatalytic behaviors and solid state fluorescent properties at room temperature have been investigated in detail.

Assembly of organic-inorganic hybrid supramolecular materials based on basketlike {M⊂P6Mo18O73} (M = Ca, Sr, Ba) cage and transition-metal complex.

Eight members of basketlike mixed-valent compounds, formulated as {H(3)O}(2){Fe(III)(2,2'-bpy)(3)}(6){Sr⊂P(6)Mo(V)(4)Mo(VI)(14)O(73)}(2)·9H(2)O (1), {H(2)(4,4'-bpy)}(5){[Ni(4,4'-bpy)(H(2)O)(3)](2)[Ni(H(2)O)(2)][Sr⊂P(6)Mo(V)(2)Mo(VI)(16)O(73)](2)}·12H(2)O (2), {Cu(2)(bim)(4)(H(2)O)}(2){[Cu(bim)(2)](2)[Cu(bim)(H(2)O)](2)Cu(H(2)O)(2)[Sr⊂P(6)Mo(V)(3)Mo(VI)(15)O(73)](2)}·16H(2)O (3), {H(3)O}(4){[Cd(phen)(2)](2)Sr(H(2)O)(5)[Sr⊂P(6)Mo(V)(4)Mo(VI)(14)O(73)]}·H(2)O (4), {Cu(bim)(2)} {[Cu(bim)(2)](2)[Cu(Hbim)(H(2)O)(2)][Ca⊂P(6)Mo(V)(3)Mo(VI)(15)O(73)]}·9H(2)O (5), {[Cu(2,2'-bpy)(H(2)O)](4)[Ca⊂P(6)Mo(V)(2)Mo(VI)(16)O(73)]}·4H(2)O (6), {[Cu(2,2'-bpy)(H(2)O)](4)[Sr⊂P(6)Mo(V)(2)Mo(VI)(16)O(73)]}·8H(2)O (7), and {[Cu(2,2'-bpy)(H(2)O)](4)[Ba⊂P(6)Mo(V)(2)Mo(VI)(16)O(73)]}·8H(2)O (8), have been hydrothermally synthesized and structurally characterized via elemental analysis, thermogravimetry (TG), infrared (IR) spectroscopy, ultraviolet-visible light (UV-vis) spectroscopy, X-ray photoelectron spectroscopy (XPS), and single-crystal X-ray diffraction (XRD). The structural analysis shows that all the compounds contain basket-shaped polyoxoanions [M⊂P(6)Mo(V)(n)Mo(VI)(18-n)O(73)]((6+n)-) (M = Ca, Sr, Ba; n = 2, 3, or 4) (abbreviated as {P(6)Mo(18)O(73)}) as building units, which consists of a tetravacant γ-Dawson-type{P(2)Mo(14)} unit and a "handle"-shaped {P(4)Mo(4)} segment encapsulating a single alkaline-earth metals cation M(2+) in the central cavity. Compound 1 presents a zero-supported basketlike structure decorated by three discrete {Fe(2,2'-bipy)(3)} fragments. Compound 2 is monosupported by {Ni(4,4'-bipy)(H(2)O)(3)} subunit. Compound 3 and 4 are bisupported by copper complexes and cadmium complexes, respectively. Compound 5 exhibit a trisupported basket cluster modified with two {Cu(bim)(2)}(2+) and one {Cu(Hbim)(H(2)O)}(3+) cations. Compounds 6-8 are isostructural clusters exhibiting similar tetra-supported structures. Compound 1, 2, and 4 represent the first basket-like hybrids containing transition-metal iron, nickel, and cadmium, respectively. In addition, compounds 2, 6, 7, and 8 are observed for the first time as a two-electron-reduced basket form. The compounds display good electrocatalytic activity upon the reduction of nitrite, and fluorescent properties.

catena-Poly[[(2,2'-bipyidine-2κ(2)N,N')-µ-cyanido-1:2κ(2)N:C-dicopper(I)]-µ-bromido-[(2,2'-bipyidine-2κ(2)N,N')-µ-cyanido-1:2κ(2)N:C-dicopper(I)]-µ-cyanido-κ(2)N:C].

In the title complex, [Cu(4)Br(CN)(3)(C(10)H(8)N(2))(2)](n), the four independent Cu(I) atoms are all in distorted trigonal-planar geometries. One is formed by one N atom and one C atom from two cyanide groups and one Br atom, one is formed by two N atoms from two cyanide groups and one Br atom, and the other two are formed by two N atoms from a chelating 2,2'-bipyridine (bpy) ligand and one C atom from a cyanide group. The structure exhibits a zigzag chain backbone along [101] constructed by bromide and cyanide anions bridging the Cu(I) atoms, with the [Cu(bpy)(CN)] units pointing laterally.

Influence of pH and organic ligands on the supramolecular network based on molybdenum phosphate/strontium chemistry.

Three supramolecular materials based on different poly(oxomolybdophosphate) clusters, (H(2)imi)(6)(Himi)(4)[{Sr(H(2)O)(4)}(2){Sr ⊂ P(6)Mo(4)(V)Mo(14)(VI)O(73)}(2)]·17H(2)O (1), (H(2)(4,4'-bpy))(2)[Cu(2)Sr(2)Mo(12)O(24)·(OH)(6)(H(2)O)(6)(H(2)PO(4))(2)(HPO(4))(2)(PO(4))(4)]·5H(2)O (2), and (H(2)bim)(H(2)bim)[SrP(2)Mo(5)O(23)(H(2)O)(3)]·2H(2)O (3) (imi = imidazole, 4,4'-bpy = 4,4'-bipyridine, and bim = 2,2'-biimidazole), have been hydrothermally synthesized and structurally characterized by the elemental analysis, TG, IR, UV-vis, XPS and the single-crystal X-ray diffraction. Compound 1 is made up of unusual basket-shape [Sr ⊂ P(6)Mo(18)O(73)](10-) cages linked by [Sr(H(2)O)(4)](2+) fragments to yield unprecedented dimeric chains, which represent the first 1-D assemblies of basket-type POMs. Compound 2 exhibits a novel string constructed from sandwich-like [Cu(P(4)Mo(6)O(31))(2)] units and {Sr(2)Cu} trinuclear linkers. Compound 3 is the first chain of Strandberg-type polyoxoanions connected by Sr(2+) cations. All the 1-D chains are further packed into various 3-D supramolecular assemblies via strong hydrogen-bonding interactions. The electrochemical and electrocatalysis behavior of 1, 2, and 3-CPE have been investigated in detail.

A new organic-inorganic hybrid layered molybdenum(V) cobalt phosphate constructed from [H24(Mo16O32)Co16(PO4)24(OH)4(C5H4N)2(H2O)6](4-) wheels and 4,4'-bipyridine linkers.

A new layered molybdenum cobalt phosphate, Na(2)[Co(H(2)O)(6)][(Mo(16)O(32))Co(16)(PO(4))(4) (HPO(4))(16)(H(2)PO(4))(4)(OH)(4)(C(10)H(8)N(2))(4)(C(5)H(4)N)(2)(H(2)O)(6)]·4H(2)O (1), has been hydrothermally synthesized and structurally characterized. 1 crystallizes in the monoclinic space group P2(1)/n with a = 15.6825(18) Å, b = 39.503(4) Å, c = 17.2763(17) Å, ß = 93.791(2)°, V = 10679.4(18) Å(3), and Z = 2. A polyoxoanion of 1 exhibits an unusual organic-inorganic hybrid wheel-type cluster, in which two pyridine ligands link to the surface Co(II) atoms of a [H(24)(Mo(16)O(32))Co(16)(PO(4))(24)(OH)(4)(H(2)O)(6)] (namely, {Mo(16)Co(16)P(24)}) wheel via the Co-N bonds. Furthermore, each {Mo(16)Co(16)P(24)} wheel is connected to four adjacent wheels by four pairs of 4,4'-bipyridine linkers, forming a 2D layered network. The susceptibility measurement shows the existence of dominant antiferromagnetic interactions in 1.

Tetra-imidazolium hexa-µ(4)-oxido-dodeca-µ(2)-oxido-dodeca-oxidohexa-arsenate(III)hexa-molybdenum(VI)cuprate(II).

The title compound, (C(3)H(5)N(2))(4)[As(6)CuMo(6)O(30)], is made up of a centrosymmetric anionic cluster and four imidazolium cations. In the cluster, the central Cu(II) atom is six-coordinated and lies on an inversion center. Adjacent clusters are linked via N-H⋯O hydrogen bonds between the imidazole cations and polyoxidoanions into a three-dimensional supra-molecular architecture.

A new molybdenum(V) nickel phosphate based on divacant [H30(Mo(V)16O32)Ni14(PO4)26O2(OH)4(H2O)8]12- wheel.

A new molybdenum nickel phosphate, [H(2)en](3)Na(4)[Ni(H(2)O)(3)][H(30)(Mo(V)(16)O(32))Ni(14)(PO(4))(26)O(2) (OH)(4)(H(2)O)(8)] x 8 H(2)O 1, has been hydrothermally synthesized and structurally characterized. Compound 1 crystallizes in the monoclinic space group P2(1)/c with a = 18.6118(6) A, b = 20.9879(6) A, c = 22.9360(5) A, beta = 116.678(2) degrees, V = 8005.5(4) A(3) and Z = 2. The polyoxoanion of 1 exhibits an unusual divacant wheel-type cluster in which two {NiO(6)} octahedra are lost from the well-known "saturated" {Mo(16)TM(16)P(26)} wheel. The two vacant sites are occupied by two protonated ethylenediamines (H(2)en) via the strong hydrogen-bonding interactions between the surface O atoms of the polyoxoanions and the amine group derived from the H(2)en ligands. DC susceptibility measurements show that compound 1 exhibits strong antiferromagnetic interactions inside the wheel-type cluster.