Crystal Structure and Thermal Properties of Double-Complex Salts [M(NH)][M(CO)] (M, M = Co, Rh) and K[Rh(NH)][Rh(CO)]∙6HO.

Here, seven new double-complex salts, [M(NH)][M(CO)] (M, M = Co, Rh) and K[Rh(NH)][Rh(CO)]∙6HO types, are synthesised. The crystal structure and composition of DCS (double-complex salts) are studied by SCXRD, XRD, CHN and IR methods. The complex salts of the [M(NH)][M(CO)] (M, M = Co, Rh) type can be crystallised both as a crystalline hydrate [M(NH)][M(CO)]·3HO (sp.

Preliminary exploration of direct mercury speciation in solid samples by using thermal release coupled to electrothermal atomic absorption spectrometry.

It is known that monitoring of mercury and notably its species is very important to assess their impact and distribution in the environment. In this regard, the development of a methodology for mercury speciation in natural and man-made media is of particular importance. There are a variety of studies in this area associated with the application of thermal release in combination with electrothermal atomic absorption detection for direct mercury speciation in solid samples without preliminary extraction of analytes.

Efficient Production of Segmented Carbon Nanofibers via Catalytic Decomposition of Trichloroethylene over Ni-W Catalyst.

The catalytic utilization of chlorine-organic wastes remains of extreme importance from an ecological point of view. Depending on the molecular structure of the chlorine-substituted hydrocarbon (presence of unsaturated bonds, intermolecular chlorine-to-hydrogen ratio), the features of its catalytic decomposition can be significantly different. Often, 1,2-dichloroethane is used as a model substrate.

Single-Walled Carbon Nanotubes with Red Phosphorus in Lithium-Ion Batteries: Effect of Surface and Encapsulated Phosphorus.

Single-walled carbon nanotubes (SWCNTs) with their high surface area, electrical conductivity, mechanical strength and elasticity are an ideal component for the development of composite electrode materials for batteries. Red phosphorus has a very high theoretical capacity with respect to lithium, but has poor conductivity and expends considerably as a result of the reaction with lithium ions. In this work, we compare the electrochemical performance of commercial SWCNTs with red phosphorus deposited on the outer surface of nanotubes and/or encapsulated in internal channels of nanotubes in lithium-ion batteries.

Adsorption kinetics of NO gas on oxyfluorinated graphene film.

We report the fabrication of high-performance NO gas sensors based on oxyfluorinated graphene (OFG) layers. At room temperature, the times of adsorption/desorption of NO on/from the surface of thin OFG films are less than 1200 s and can be reduced by increasing the operation temperature. The sensors are capable of detecting NO molecules at sub-ppm level with a sensitivity of 0.

Porous Co-Pt Nanoalloys for Production of Carbon Nanofibers and Composites.

The controllable synthesis of carbon nanofibers (CNF) and composites based on CNF (Metals/CNF) is of particular interest. In the present work, the samples of CNF were produced via ethylene decomposition over Co-Pt (0-100 at.% Pt) microdispersed alloys prepared by a reductive thermolysis of multicomponent precursors.

Synthesis and investigation of the thermal properties of [Co(NH)][Co(CO)]·3HO and [Ir(NH)][Ir(CO)].

The complexes [Co(NH)][Ir(CO)] and [Ir(NH)][Co(CO)]·HO have previously been synthesized and their thermal properties studied. The [Ir(NH)][Ir(CO)] and [Co(NH)][Co(CO)]·3HO complexes considered here are the end members in a series of possible isostructural solid solutions based on the complex salts in the Co-Ir system. Their crystal structures and thermal properties are described in detail, including temperature-dependent in situ X-ray diffraction.

Doping of Carbon Nanotubes with Encapsulated Phosphorus Chains.

Single-walled carbon nanotubes (SWCNTs) are a perfect host for the formation of one-dimensional phosphorus structures and to obtain hybrid materials with a large P-C ratio. This work presents a procedure for high-yield phosphorus filling of commercial Tuball SWCNTs and efficient removal of phosphorus deposits from the external nanotube surface. We probed white and red phosphorus as precursors, varied the synthesis temperature and the ampoule shape, and tested three solvents for sample purification.

Thermophysical properties of lithium thiogallate that are important for optical applications.

Lithium thiogallate LiGaS is one of the most common nonlinear crystals for mid-IR due to its extreme beam strength and wide transparency range; however, its thermophysical properties have not yet been practically studied. Large crystals of high optical quality are grown. DTA revealed features at 1224 K below melting point (1304 K) that are associated with the oxygen containing compounds of the LiGaO S type.

Formation of Catalytically Active Nanoparticles under Thermolysis of Silver Chloroplatinate(II) and Chloroplatinate(IV).

The thermal behaviour of Ag[PtCl] and Ag[PtCl] complex salts in inert and reducing atmospheres has been studied. The thermolysis of compounds in a helium atmosphere is shown to occur in two stages. At the first stage, the complexes decompose in the temperature range of 350-500 °C with the formation of platinum and silver chloride and the release of chlorine gas.

Tetranitratopalladate(II) Salts with Tetraalkylammonium Cations: Structural Aspects, Reactivity, and Applicability toward Palladium Deposition for Catalytic Applications.

A series of salts (RN)[Pd(NO)] (R = CH, CH, n-CH; -) were synthesized in high yield from a nitric acid solution of palladium. The salts were characterized by a combination of physicochemical methods, and their crystal structures were determined by X-ray diffraction. The conformation of the [Pd(NO)] anion was studied in detail using crystal structure data and density functional theory calculations.

One-Dimensional Diiodine-Iodobismuthate(III) Hybrids Cat{[BiI](I)}: Syntheses, Stability, and Optical Properties.

One-dimensional iodine-rich iodobismuthates(III), Cat{[BiI](I)} [Cat = 1,4-MePy () and 1-EtBMAP ()], feature the highest amount of "trapped" diiodine units in polyhalogen-halometalates of p-block elements. Both complexes have narrow optical band gaps (1.55 and 1.

Preparation of porous Co-Pt alloys for catalytic synthesis of carbon nanofibers.

A simple and convenient procedure for the production of highly dispersed porous Co-Pt alloys to be used as catalysts for the synthesis of nanostructured carbon fibers (CNF) has been developed. The technique is based on the thermal decomposition of specially synthesized multicomponent precursors in a reducing atmosphere. A series of porous single-phase alloys Co-Pt (10-75 at% Pt) have been synthesized.

Insight into the thermal decomposition of ammonium hexahalogenoiridates(IV) and hexachloroiridate(III).

Thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6] in reductive and inert atmospheres has been investigated in situ using quick-EXAFS and temperature-resolved powder X-ray diffraction. For the first time, (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] have been proven as intermediates of thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6]. Thermal degradation of (NH4)2[IrCl6] and (NH4)2[IrBr6] is a more complex process as suggested previously and includes simultaneous formation of (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] intermediates mixed with metallic iridium.

Luminescent Zn(ii) and Cd(ii) complexes with chiral 2,2'-bipyridine ligands bearing natural monoterpene groups: synthesis, speciation in solution and photophysics.

Mononuclear zinc(ii) and cadmium(ii) complexes, ZnLCl2 (1), CdLCl2 (2), ZnL1Cl2·2H2O (3), and CdL1Cl2·2H2O (4), with chiral ligands containing a 2,2'-bipyridine moiety and natural terpene (+)-limonene (L) or (+)-3-carene (L1) moieties were synthesized. In these complexes the L and L1 ligands are shown to coordinate Zn2+ and Cd2+ ions through the 2,2'-bipyridine moiety. The acetamide group of the ligands interacts with M2+ ions by forming NM2+ and C[double bond, length as m-dash]OM2+ contacts and N-HCl hydrogen bonds with coordinated Cl- ions.

Light-Induced Sulfur Transport inside Single-Walled Carbon Nanotubes.

Filling of single-walled carbon nanotubes (SWCNTs) and extraction of the encapsulated species from their cavities are perspective treatments for tuning the functional properties of SWCNT-based materials. Here, we have investigated sulfur-modified SWCNTs synthesized by the ampoule method. The morphology and chemical states of carbon and sulfur were analyzed by transmission electron microscopy, Raman scattering, thermogravimetric analysis, X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopies.

Tetraammineplatinum(II) and Tetraamminepalladium(II) Chromates as Precursors of Metal Oxide Catalysts.

[M(NH ) ]A (M=Pt, Pd; A=CrO , Cr O ) and [Pt(NH ) (NO )(Cr O )]NO complex salts were synthesized and characterized by a number of physicochemical methods of analysis (IR, single-crystal and powder XRD, and simultaneous thermogravimetry and differential scanning calorimetry with evolved gas analysis mass spectrometry). Thermolysis of the salts obtained in a hydrogen atmosphere proceeds with the partial reduction of chromium to a metallic state and the formation of M Cr (M=Pt, Pd) metal solid solution with a chromium content of up to 22 at % and chromium(III) oxide. The thermal decomposition of salts in an inert and oxidizing atmosphere passes through the formation stage of the MCrO phase with the delafossite structure followed by its subsequent decomposition into chromium(III) oxide and noble metal.

Effect of Mo on the catalytic activity of Ni-based self-organizing catalysts for processing of dichloroethane into segmented carbon nanomaterials.

A series of micro-disperse Ni-Mo alloys with the sponge-like structure was prepared by a simultaneous precipitation method followed by sintering of the sediment in H atmosphere at 800 °C. According to XRD data, the formation of single-phase solid solution NiMo took place for the samples with Mo content of 0.6-8.

Percolative Composites with Carbon Nanohorns: Low-Frequency and Ultra-High Frequency Response.

We systematically studied the electromagnetic properties of carbon nanohorns (CNHs) and polystyrene composites filled with CNHs in static regime, low frequency and microwave regions. CNHs were synthesized using the direct current arc-discharge method using solid graphite rods and graphite rods filled by melamine mixed with graphite powder. Transmission electron microscopy and thermo-gravimetric analysis showed that CNH agglomerates are the main product, while the addition of melamine promotes the formation of graphite balls.

Bromo- and Polybromoantimonates(V): Structural and Theoretical Studies of Hybrid Halogen-Rich Halometalate Frameworks.

Cation-dependent reactions "[SbBr ] +Br +HBr+CationBr " result in the formation of bromide/polybromide complexes with zero-, one-, two-, or three-dimensional supramolecular frameworks and different Br/Sb ratios (up to 11). Seven new compounds representing six structural types were characterized by XRD and thermogravimetric analysis and DFT calculations enabled estimation of the energies of the Br⋅⋅⋅Br contacts (1.1-4.

Porous Nanocrystalline Silicon Supported Bimetallic Pd-Au Catalysts: Preparation, Characterization, and Direct Hydrogen Peroxide Synthesis.

Bimetallic Pd-Au catalysts were prepared on the porous nanocrystalline silicon (PSi) for the first time. The catalysts were tested in the reaction of direct hydrogen peroxide synthesis and characterized by standard structural and chemical techniques. It was shown that the Pd-Au/PSi catalyst prepared from conventional H[PdCl] and H[AuCl] precursors contains monometallic Pd and a range of different Pd-Au alloy nanoparticles over the oxidized PSi surface.

Preparation of Zr(Mo,W)O with a larger negative thermal expansion by controlling the thermal decomposition of Zr(Mo,W)(OH,Cl)∙2HO.

Solid solutions of Zr(Mo,W)O(OH,Cl)∙2HO with a preset ratio of components were prepared by a hydrothermal method. The chemical composition of the solutions was determined by energy dispersive X-ray spectroscopy (EDX). For all the samples of ZrMoWO(OH,Cl)∙2HO (x = 0.

Bromine-rich complexes of bismuth: experimental and theoretical studies.

Three novel polybromide complexes of bismuth(iii) - (2,6-MePyH)[BiBr(Br)] (1), (Hbpp){[BiBr](Br)} (2) and (3-ClPyH){[BiBr](Br)} (3) - were synthesized. The results of an extended screening involving a set of organic cations resulting in the formation/non-formation of Bi(iii) polybromides are presented and discussed. The nature of BrBr interactions in Bi(iii) polybromides was investigated by theoretical methods, enabling the estimation of their energies.

Synthesis and Concentration of Organosols of Silver Nanoparticles Stabilized by AOT: Emulsion Versus Microemulsion.

In this work, we tried to combine the advantages of microemulsion and emulsion synthesis to obtain stable concentrated organosols of Ag nanoparticles, promising liquid-phase materials. Starting reagents were successively introduced into a micellar solution of sodium bis-(2-ethylhexyl)sulfosuccinate (AOT) in n-decane in the dynamic reverse emulsion mode. During the contact of the phases, Ag passes into micelles and Na passes into emulsion microdroplets through the cation exchange AOTNa + AgNO = AOTAg + NaNO.