Proton conductivity of composites based on Nafion and silica matrices with a chemically modified surface

The surface of aerosilogel and macroporous and microporous glasses was modified with aromatic sulfo groups (≡Si(CH₂)₂-C₆H₄-SO₃H) by the chemical assembly method. Composite solid electrolytes containing Nafion were prepared from the silica matrices with a chemically modified surface. The proton conductivity of the materials was studied by impedance spectroscopy. Composite materials based on Nafion and aerosilogel matrices and macroporous glasses with grafted ≡Si(CH₂)₂-C₆H₄-SO₃H groups showed the highest proton conductivity.     

Perovskites with the Framework‐Forming Xenon

The Group 18 elements (noble gases) were the last ones in the periodic system to have not been encountered in perovskite structures. We herein report the synthesis of a new group of double perovskites KM(XeNaO₆) (M=Ca, Sr, Ba) containing framework‐forming xenon. The structures of the new compounds, like other double perovskites, are built up of the alternating sequence of corner‐sharing (XeO₆) and (NaO₆) octahedra arranged in a three‐dimensional rocksalt order. The fact that xenon can be incorporated into the perovskite structure provides new insights into the problem of Xe depletion in the atmosphere. Since octahedrally coordinated Xe^VIII and Si^IV exhibit close values of ionic radii (0.48 and 0.40 Å, respectively), one could assume that Xe^VIII can be incorporated into hyperbaric frameworks such as MgSiO₃ perovskite. The ability of Xe to form stable inorganic frameworks can further extend the rich and still enigmatic chemistry of this noble gas.     

Structural features and transport processes of superionic conductors based on tin(II) fluoride

The thermal behavior and transport properties of lead(II) tetrafluorostannate(II) have been investigated by impedance spectroscopy,¹⁹F NMR and high hydrostatic pressure techniques. It is shown that these experimental methods are powerful tools to clarify ionic transport processes in the investigated solid electrolytes with predominant fluorine mobility. Paper presented at the 3rd Euroconference on Solid State Ionics, Teulada, Sardinia, Italy, Sept. 15–22, 1996     

Synthesis,Interatomic Interactions,Structure, and Conductivity of Lanthanum Gallate Doped with Nickel and Magnesium

Russian Journal of General Chemistry - The coexistence of two crystal modifications of lanthanum gallate, orthorhombic and rhombohedral, was revealed for the first time in two series of solutions:...     

Open-circuit polarization of a porous platinum electrode in an atmosphere with a changing oxygen content: Comparing a polarization equation to experimental results

The dependence of overpotential on emf of a porous platinum electrode polarized under open-circuit conditions is analyzed on the basis of a polarization equation. The electrode is situated on the surface of a solid-electrolyte cell of 0.9ZrO₂ + 0.1Y₂O₃ in an atmosphere containing oxygen, inert gas, and carbon dioxide or water vapor. A comparison with the experiment is performed. Deceased.     

Open-circuit polarization of a porous platinum electrode in an atmosphere with a changing oxygen content: Diffusion model and equation for polarizing flux

A diffusion-kinetic model for an open-circuit polarization of a porous platinum electrode is considered. The electrode is situated on the surface of a solid-electrolyte cell of 0.9ZrO₂ + 0.1 Y₂O₃ in an atmosphere containing oxygen, inert gas, and carbon dioxide or water vapor. Deceased.     

Atom states and interatomic interactions in perovskite-like oxides: XXVII. Influence of strontium concentration on interatomic interactions and conductivity in lanthanum gallates doped with strontium and chromium

Solid solutions based on lanthanum gallate and containing chromium and strontium in the ratio 2:1 as doping elements were studied by the method of static magnetic susceptibility, electron paramagnetic resonance spectroscopy, and impedance spectroscopy. Clustering of chromium atoms resulting in the formation of large aggregates of paramagnetic atoms is strengthened as the amount of strontium in the system increases.     

Studying the semiconductor-metal phase transition in nanoscale vanadium dioxide, doped with ions of 3d-elements on a silicon surface

Nanoscale vanadium dioxide doped with chromium and iron is obtained via molecular layering method on the surface of a single-crystal silicon. The qualitative and quantitative composition of the samples is determined by photometry and magnetochemical analysis. The morphology is examined by AFM and SEM. Two independent methods (magnetic susceptibility and impedance spectroscopy) show the presence of the semiconductor-metal phase transition in the obtained structures in the range 100–125 K. The considerable influence of the alloying element content on the characteristics of the phase transition, including its temperature, is established.