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In this work, a facile aqueous synthesis strategy was used (complete in 5 min at room temperature) to produce large-size Pd, PdCu, and PdPtCu nanomeshes without additional organic ligands or solvent and the volume restriction of reaction solution. The obtained metallic nanomeshes possess graphene-like morphology and a large size of dozens of microns. Abundant edges (coordinatively unsaturated sites, steps, and corners), defects (twins), and mesopores are seen in the metallic ultrathin structures. The formation mechanism for porous Pd nanomeshes disclosed that they undergo oriented attachment growth along the ⟨111⟩ direction. Owing to structural and compositional advantages, PdCu porous nanomeshes with certain elemental ratios (e. g., Pd87 Cu13 ) presented enhanced electrocatalytic performance (larger mass activity, better CO tolerance and stability) toward ethanol oxidation.

K2AgIn3Se6 was synthesized by a molten-salt (alkali-metal polyselenide flux) reaction at 500 C. The orange red granular crystal crystallizes in monoclinic space group C2/c with cell parameters, a =1.16411(7) nm, b= 1.16348(8) nm, c=2.14179(12) nm, V=2.8740(9) nm3, and Z=8. The crystal has a new two-dimensional structure containing 2-−[AgInSe6]2-− anionic layers separated by K+ cations and the 2-−[AgIn3Se6]2-− layer is constructed with comer-shared [AgSe4] and [InSe4] tetrahedra. The optical band gap of K2AgIn3Se6 was determined to be ca. 2.9 eV by UV/vis/NIR diffuse reflectance spectra.

A novel one-dimensional coordination polymer, Catena-poly [bis(4-cyano-pyridyl) copper(II)-di-thiocyanate], 1∞ [CuII-(cypy)2(μN.S-SCN)2] (cypy = 4-cyano-pyridyl), was synthesized in a solution reaction of Cu(NO3)2·3H2O, 4-cyano-pyridine and KSCN in mole ratio of 1:2:2 at room temperature. Its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic crystal system, space group P21/c with cell parameters a = 1.0719(2), b = 1.8441(4), c =0.9144(2) nm, β = 110.49(3)° and Z = 4. A full-matrix least-squares refinement gave R1 = 0. 0393 and wR2= 0.0916 for 1554 reflections having 1 >2σ(I). The crystal is thermally stable up to approximately 170 °C.

A novel coordination polymer, [Ag4ppdc)(H2bpdc)(Hbpdc)2] (bpdc = 2,2′-bipyridyl-3,3′-dicarboxylate), was hydrothermally synthesized at 403 K and structurally characterized by single crystal X-ray diffraction analysis. The compound crystalizes in the monoclinic space group C2/c with a=1.9516(4) nm, b=1.9503(4) nm. c=1.2566(3) nm, and β=112.48(3)°. In the two-dimensional crystal structure, AgI center is coordinated, in a scarce coordination environment, double-capped tetrahedron, by one bpdc ligand to form N-Ag-N chelate bond via two pyridyl N atoms, and other two bpdc ligands to form two O-Ag-O chelate bonds, respectively, via two carboxyl O atoms. The bpdc ligands are present in one non-protonated form, bpdc, and two protonated forms, Hbpdc and H2bpdc, which all act as μ3-ligand in a hexadentate fashion (N, N′; O, O′; O, O′) to coordinate with three Ag centers, respectively, through the three chelate bonds. This coordinated fashion of bpdc ligand is first found in the title compound. W-Us-NIR reflectance spectroscopy study revealed insulator nature for the crystal with an optical energy gap of 3.1 eV.

Three coordination polymers, Ln2(bpdc)3(phen)2(H2O)2 (Ln=Nd(1), Eu(2), and Tb (3); bpdc=2,2′-bipyridine-3,3′-dicarboxylate; phen=1,10-phenanthroline), were obtained by hydrothermal reaction of Ln2O3 with 2,2′-bipyridine-3,3′-dicarboxylate acid, and 1,10-phenanthroline. They were characterized by single-crystal X-ray diffraction, IR spectra, and photoluminescent spectra. The crystallographic data of 1–3 indicated that they were isostructural. Both complexes contained paddle-wheel building blocks, formed by bpdc and phen ligands. These paddle-wheel secondary building units (SBUs) were further connected to form two-dimensional (2-D) metal organic framework (MOF) networks by 2,2′-bipyridine-3, and 3′-dicarboxylate linkers. A three-dimensional (3-D) supramolecular structure was formed by π–π aromatic interactions between adjacent 2-D infinite networks. Photoluminescent measurements indicated that europium compound 2 and terbium compound 3 were strong, red and green emitters, respectively.

Three monofunctionalized organoimido derivatives of [Mo6O19]2− bearing an electron-withdrawing chloro group (R = p-ClC6H4 1, m-ClC6H4 2, or o-ClC6H4 3) have been prepared in high purity and moderate to good yields using an easy reaction route of [α-Mo8O26]4− with corresponding aromatic amine hydrochlorides or a mixture of aromatic amines and their hydrochloride salts in the presence of N,N′-dicyclohexylcarbodiimide (DCC). These complexes have been characterized by 1H NMR, IR, UV–Vis, UV–Vis-NIR reflectance spectroscopy, cyclic voltammetry, and their semiconductive and redox properties were explored by these techniques. Their electronic absorption spectra were also interpreted based on first-principles electronic structure calculations and these features of the simulated spectra are qualitatively consistent with the observed UV spectra. Additionally, the composition and structure of compounds 1 and 2 were further confirmed by X-ray single-crystal diffraction studies.

In this paper, a series of rare earth carbonate nanostructures were synthesized in the reverse micelle system and the influences of experimental conditions on the growth of the product crystals wer...

Single-crystal hydroxyapatite (HAP) nanorods have been successfully synthesized by the reverse microemulsion method, and characterized by high-resolution transmission electron microscope (HRTEM), infrared spectra (IR), and powder X-ray diffraction (XRD). In this work, the feasibility of using quaternary reverse microemulsion (TX-100 + CTAB/ n -butanol + n -hexanol/cyclohexane/water) to prepare hydroxyapatite nanorods with diameter 8–15 nm and length 25–50 nm, is described. The homogeneity in size and shape of hydroxyapatite nanoparticles observed by TEM is probably attributed to the different stabilization functions of different kinds of surfactant on the interfacial film.

LaPO4 nanofibers were synthesized and their bundle-like assemblies were investigated in reverse micelles system. Techniques of XRD, XPS, TEM, SEM and UV–vis absorption spectra were used to characterize the morphology, structure and composition of the nanofibers and the bundle-like products. The experimental results show that the obtained LaPO4 nanofibers are large aspect-ratio and narrow distribution of diameter and their assembly process can be regulated through the control of different experimental parameters. The possible mechanism of bundle-like assemblies was also proposed.

An organic–inorganic hybrid compound, (Bu4N)2[Mo6O18(NAr)] (Ar = p-BrC6H4) has been synthesized via the DCC dehydrating protocol of the reaction of [α-Mo8O26]4− with 4-bromoaniline hydrochloride in anhydrous acetonitrile, which has been characterized by UV–Vis spectra, 1H NMR and single crystal X-ray diffraction study. By comparing the UV–Vis spectra, which were used to monitor the reaction, the optimum preparative condition for this compound was also determined. This compound crystallizes in the monoclinic space group P21/n, which is featured in a terminal para-bromophenylimido group linked to an Mo atom of a hexamolybdate cluster by a Mo–N triply bond. In addition, there are π–π dimerization of the neighboring cluster anions though the parallel aromatic rings in their crystals.

A kinetically controlled trans bifunctionalized organoimido derivative of hexamolybdate, (n-Bu(4)N)(2){trans-[Mo(6)O(17)(NAr)(2)]} (Ar = 2,6-dimethylphenyl) 1, in which the two 2,6-dimethylphenylimido groups are bonded to hexamolybdate at the trans positions, has been successfully synthesized in ca. 60% yield under mild reaction conditions. Its trans structure has been confirmed by a single-crystal X-ray diffraction study. In the crystals, cluster anions of 1 self-assemble into a 3D netlike structure via two different kinds of C-H...O hydrogen bondings, in which 1D supramolecular rectangular channels containing tetrabutylammonium cations form along the a axis. Compound 1 has also been characterized by (1)H NMR, IR, and UV-vis spectroscopic studies. UV-vis-near-IR reflectance spectroscopy measurements reveal the compound's nature of semiconductivity with an optical energy gap of 2.55 eV.

A novel organic−inorganic hybrid solid, (n-Bu4N)2[Mo6O17(NAr)2] (Ar = o-CH3OC6H4) 1, has been prepared by refluxing of (n-Bu4N)2[Mo6O19] and appropriate o-anisidine in acetonitrile with N-N‘-dicyclohexylcarbodiimide (DCC) as the dehydrating agent. Compound 1 has been characterized by single-crystal X-ray diffraction. Both of the two terminal o-anisidido ligands are linked, respectively, to an Mo atom of the hexamolybdate in a terminal fashion and exhibit an almost linear coordination mode of the Mo⋮N triple bond character. The two o-anisidido aryl rings on the hexamolybdate cluster lie in the cis position, allowing π−π stacking of phenyl ring among the anions. In the crystal, the cluster anions of 1 aggregate into an interesting 1D double chain along the a-axis through π−π stacking and C−H···O hydrogen-bonding interactions. Compared to the hexamolybdate parent, this solid has a smaller optical band gap of 2.25 eV from UV−visible-near-IR reflectance spectroscopy studies. It has also been characterized by 1...

A variety of novel La 2 (CO 3 ) 3 nanostructures, such as nanowires, nanobelts and ramiform superstructures, have been synthesized in the Triton X-100/cyclohexane/water reverse micelles system. These nanostructures could be obtained at pH 2–5 and the length of nanowires was seen to increase with increase in aging time. Nanobelts or flakelike La 2 (CO 3 ) 3 nanowire bundles formed at low aging temperature; however, ramiform superstructures could be obtained at high temperature. The growth mechanism combined with the Ostwald ripening process and oriented attachment process was proposed to the La 2 (CO 3 ) 3 nanostructures.

In the presence of N, N′-dicyclohexylcarbodiimide (DCC), (Bu4N)2[Mo6O18(NAr)] (1) and (Bu4N)2[Mo6O17(NAr)2] (2), Ar = o-CH3C6H4, have been synthesized via the reaction of [α-Mo8O26]4— with o-toluidine. If the hydrochloride salt of o-toluidine was added into the reactive mixture, only the monofunctionalized imido derivative of [Mo6O19]2— was obtained; the bifunctionalized derivative of [Mo6O19]2— was exclusively synthesized in the presence of non-protonated o-toluidine. The molecular and crystal structures of the hybrid compounds 1 and 2 were determined by X-ray single crystal diffraction, and their UV, IR and NMR spectra were compared. Additionally, a possible reaction mechanism was proposed.

Hydroxyapatite (HAP) nanoparticles have been successfully synthesized by reverse microemulsion (aqueous solution/mixed TX-100 and Tween 80/mixed n-butanol and n-hexanol/cyclohexane) at room temperature. In comparison with HAP particles, prepared by conventional direct precipitation method, the reverse microemulsion route led to a significant improvement in the particle size and the degree of particle agglomeration. The effect of different hydrophile–lipophile balance (HLB) values on the particle size was also discussed.

A hydrothermal reaction of WO3, CoCl2 and 4,4′-bipyridine, yields a novel organic–inorganic hybrid compound, Co2(bpy)6(W6O19)2, at 170°C. X-ray single crystal structure determination reveals a two-dimensional covalent structure belonging to monoclinic crystal system, space group C2/c, with cell parameters a=19.971(4) A, b=11.523(2) A, c=16.138(3) A, β=96.49(3)°, V=3690.0 A3 and Z=2. The hexatungstate, [W6O19]2−, acts as a building block in bidentate fashion to bridge the Co(II) centers in the crystal structure. The title compound is found to have an optical energy gap of 2.2 eV from UV–Vis–NIR reflectance spectra.

In the presence of a carbodiimide (DCC) a proton can dramatically speed up the reaction of α-[Mo8O26]4− with aromatic amines under mild conditions and convenient bench manipulations, which results in the easy synthesis of monofunctionalized organoimido derivatives of [Mo6O19]2− even bearing an electron-withdrawing group such as bromo or chloro groups. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A novel bifunctionalized arylimido derivative of hexamolybdate, (Bu4N)2[Mo6O17( NAr)2]2− (Ar=o-CH3C6H4) 1, in which the two o-tolylimido groups are bounded to hexamolybdate at the cis positions, was synthesized by self-assembled metathesis of α-type octamolybdate ion and o-toluidine with DCC as a dehydration agent. The most interesting characteristic of 1 is that the cluster anions form dimers via the π–π stacking between one of its two phenyl rings, and four such dimers are linked in turn via C–H⋯O hydrogen bonding involving terminal hexamolybdate oxygen atoms into ring-like tetramers in the solid state.

The title compound was synthesized by a reactive salt reaction at 773 K over a period of 5 d. It has a one-dimensional chain structure consisting of K+ cations and one-dimensional [Ag2Sn2Se6]2− anions. The chain is constructed by edge-sharing bitetrahedral [Sn2Se6] units connected in a 1:2 ratio via linear Ag+ ions.

A novel quaternary metal selenide, K2Hg3Ge2Se8, was synthesized using a molten-salt alkali–metal polyselenide flux reaction. The compound crystallized in the orthorhombic space group Aba2, a=19.851(2) A, b=10.0040(7) A, c=8.6097(7) A, V=1709.8(3) A3, Z=4. The crystal structure contains a 3-dimensional [Hg3Ge2Se8]2− framework and K+ cations located within channels of the framework.

The title compound, [Co(C(12)H(6)N(2)O(4))(H(2)O)(2)](n), has been hydrothermally synthesized and structurally characterized. It consists of polymeric chains of [Co(mu-(2,2'-bipyridyl-3,3'-dicarboxylato-kappa(4)N,N':O,O'))(H(2)O)(2)] units, in which each Co(II) cation is octahedrally coordinated by two chelating pyridyl N atoms, two chelating carboxyl O atoms from different carboxylate groups of another bipyridyl ligand, and two water molecules as terminal ligands. A crystallographic twofold axis parallel to the chain axis, passes through the Co atom.

The title compound was synthesized by a reactive salt reaction at 773 K over a period of 5 d. It has a one-dimensional chain structure consisting of K(+) cations and one-dimensional [Ag(2)Sn(2)Se(6)](2-) anions. The chain is constructed by edge-sharing bitetrahedral [Sn(2)Se(6)] units connected in a 1:2 ratio via linear Ag(+) ions.