K1.65V1.78W0.22O2(AsO4)2

The title potassium vanadium tungsten bis­(arsenate oxide) was synthesized by a solid-state reaction at 973 K. The crystal structure is isotypic with KVOPO4 and contains a [MVAs2O10]∞ framework built up from single MO6 (M = V+W) octa­hedra sharing corners with single VO6 octa­hedra and AsO4 tetra­hedra. This structure shows the existence of infinite [VAsO8]∞ and [MAsO8]∞ chains running along the a and c directions, respectively. All atoms are located on general positions. The metal position M is statistically occupied by 78% V and 22% W

K2V2O2(AsO4)2

The vanadium oxide arsenate with formula K2V2O2(AsO4)2, dipotassium divanadium(IV) dioxide diarsenate, has been synthesized by solid-state reaction in an evacuated silica ampoule. Its structure is isotypic with K2V2O2(PO4)2. The framework is built up from corner-sharing VO6 octahedra and AsO4 tetrahedra, creating an infinite [VAsO8]∞ chain running along the a- and c-axis directions. The K+ cations are located in hexagonal tunnels, which are delimited by the connection of the [VAsO8]∞ chains

A novel iron (III) organic-inorganic hybrid with a thermochromic transition: Synthesis and structural characterisation of the dicystaminium dichloride aquapentachloridoferrate (III), monohydrate (C4H14N2S2)2[FeCl5(H2O)]Cl2*H2O

International audienceThe magnetic hybrid material, based on the aquapentachloridoferrate (III), [FeCl5(H2O)]2- and on the dicystaminium cation H2Cys, is reported for the first time in this paper exhibiting an interesting thermochromic behaviour. It was prepared as orange single crystals, suitable for single crystal X-ray diffraction, with the chemical formula (C4H14N2S2)2[FeCl5(H2O)]Cl2*H2O (1). The characterization by X-ray diffraction was carried out at room temperature 296 K and at 120 K. The new derivative displays an asymmetric unit, formed by two H2Cys cations, one anionic complex [FeCl5(H2O)]2- and two Cl−, that ensure the electroneutrality, all trapped in the matrix with one water molecule. It crystallizes in the triclinic space group with the following unit cell parameter at 120 K and 296 K respectively: a = 10.7913(4) Å, b = 11.4145(5) Å, c = 11.4225(5) Å and α = 99.010(4) °, β = 102.529(4) °, γ = 90.466(3); a = 10.8747(4) Å, b = 11.4717(5) Å, c = 11.5483(4) Å and α = 98.907(3) °, β = 103.169(3) ° γ = 90.635(3). The compound was also characterized by IR spectroscopy and by DSC analysis and its magnetic behaviour was investigated

Supercapacitor electrode based on ternary activated carbon/CuCoO2 hybrid material

International audienceIn this work, a supercapacitor electrode was prepared using modified ternary activated carbon (AC ODS : Ternary Olive-Date-Sugar activated carbon) by CuCoO 2 bimetallic oxide. The hydrothermal synthesis of CuCoO 2 was successfully carried out, and then the doping on activated carbon was done. Subsequently, the characterization of the hybrid material by ATR, SEM, XRD, Zeta potential, XPS, Raman, TGA, and electrochemical methods were studied in a binary electrolyte (1 M H 2 SO 4 /KCl). The electrochemical results indicate that AC ODS /CuCoO 2 modified electrode exhibits excellent pseudo-capacitive behavior, with a specific capacitance of 1052.95 F g -1 at 0.3 A g -1 and high specific energy (161.23 Wh.kg - 1 ) at high current (8 A g -1 ). High specific capacitance of 103.12 F g -1 and a specific capacitance retention reaches up to 95.41 % after 10 4 charge-discharge cycles at 20 A g -1 were also obtained. This study revealed that the activated carbon modified with CuCoO 2 oxide offers a significant improvement in the specific capacitance and the specific energy with a high specific current. Based on these results, AC ODS /CuCoO 2 can be explored as supercapacitor electrode for energy storage, and that in terms of specific capacitance, this hybrid material gives the most important result ever obtained with this oxide

Synthesis, spectral characterization, molecular modeling, antibacterial and antioxidant activities and stability study of binuclear Pd(II) and Ru(III) complexes with novel bis-[1-(2-[(2-hydroxynaphthalen-1-yl)methylidene]amino}ethyl)-1-ethyl-3-phenylthiourea] ligand Application to detection of cholesterol

International audienceA novel bis-[1-(2-[(2-hydroxynaphthalen-1-yl) methylidene]amino}ethyl)-1-ethyl-3-phenylthiourea] Schiff base (L) and its binuclear palladium and ruthenium complexes have been prepared and characterized by ESI-MS, elemental analysis, NMR (H NMR, C NMR, COSY, NEOSY and HSQC), FT-IR, ATR, UV-Visible spectra, TGA measurements, conductivity and cyclic voltammetry. The experimental results and the molecular parameters calculated using DFT method revealed a square planar geometry around Pd and octahedral geometry around ruthenium metal. The antibacterial activity of the ligand L and its complexes was evaluated against different human bacteria. In addition, the formation constants of the synthesized Schiff base-metal complexes and the systems formed with these chelates and cholesterol were estimated using spectrophotometric technique. The detection of cholesterol using novel Pd and Ru Schiff base complexes was studied using fluorometric method, and the measurements showed that the sensitive fluorometric response towards cholesterol analysis was determined using palladium complex. The limit of detection (LOD) of cholesterol calculated using this complex (4.6 μM) is lower (better) than LOD found using ruthenium complex (19.1 μM) and different compounds previously published around linear range of 0-5 mM