Correction to: Lithium ion conductivity of solid solutions based on Li8ZrO6

Journal of Solid State Electrochemistry - Lithium ion conductivity of lithium hexaoxozirconate Li8ZrO6 doped by Mg2+, Sr2+, Nb5+, V5+, and Ce4+ cations was studied using impedance spectroscopy. The...     

Thermal and electrical properties of Ca5Mg4−xZnx(VO4)6 (0 ≤ x ≤ 4)

Calcium vanadates Ca₅Mg_4−xZn_x(VO₄)₆ (0 ≤ x ≤ 4) have been studied for the first time using a set of high-temperature methods of analysis. The onset of melting process determined from differential scanning calorimetry decreases from 1158 to 881 °C (± 1.5 °C) with increasing of x (dopant’s content). CTE temperature dependence is found to show a hysteresis. Electrical transport properties measured by impedance spectroscopy in air of different humidity are also discussed. The value of electrical conductivity does not depend on air humidity. It is found to equal to 1.5 × 10⁻⁶ S cm⁻¹ at 720 °C for Ca₅Mg₄(VO₄)₆ which is specific for garnet-related crystals.

     

Lithium intercalation into TiS<Subscript>2</Subscript> cathode material: phase equilibria in a Li–TiS<Subscript>2</Subscript> system

Lithium-intercalated titanium disulfide Li _x TiS₂ had been extensively studied as prototypical cathode material for high-energy-density reversible lithium batteries with moderate voltage. Today, this phase is one of the leading candidates for all-solid-state lithium batteries with durable high energy and high rate performance. However, fundamental knowledge of Li⁺ insertion into TiS₂ is still incomplete; available information on the phase diagram of the Li–TiS₂ system is limited by x?=?1 due to difficulties in preparing lithium-rich equilibrated samples. The goals of this work were to re-examine Li _x TiS₂ single phase boundaries and to clarify the existence of lithium-rich intercalates with x?>?1. А new preparation technique was developed to obtain 1T-Li _x TiS₂ samples as good-quality equilibrated products with desirable lithium content. Phase equilibria in a quasibinary Li–TiS₂ system were studied by X-ray diffraction, emf measurements (25 °C) and thermal analysis (25–350 °C) over a wide range of Li:Ti ratios (0 to 4).     

Synthesis,microstructure, and electric properties of CaZr<Subscript>0.9</Subscript>Y<Subscript>0.1</Subscript>O<Subscript>3 – δ</Subscript> films obtained on porous SrTi<Subscript>0.8</Subscript>Fe<Subscript>0.2</Subscript>O<Subscript>3 – δ</Subscript> supports

Compact CaZr_0.9Y_0.1O_3–δ (CZY) film on a porous SrTi_0.8Fe_0.2O_3–δ (STF) support is obtained using the technique of deposition from solutions of inorganic salts in ethanol. According to the data of scanning electron microscopy (SEM), the film has a nanoporous granular structure with the grain size of 0.2 to 1 μm. The thickness of the CZY film on the STF support is about 3 μm after 15-fold solution application. The results of studying the elemental composition showed that elements of the support diffuse into the film in the course of synthesis. Analysis of the data of impedance spectroscopy shows that conductivity of the CZY film is limited the grain bulk. It is assumed that the comparatively low conductivity activation energy of the film (50.3 kJ/mol) is due to diffusion of elements of the STF support that results in variation of the film composition and properties.     

The transport and thermal properties of glassy LiPO<Subscript>3</Subscript>/crystalline Al<Subscript>2</Subscript>O<Subscript>3</Subscript> (ZrO<Subscript>2</Subscript>) composite electrolytes

Glassy LiPO₃/crystalline Al₂O₃ and glassy LiPO₃/crystalline ZrO₂ (0–12.5 vol.% of oxide fillers) composite solid electrolytes have been prepared by glass matrix softening. Their thermal and transport properties have been investigated by differential scanning calorimetry (DSC) and impedance spectroscopy methods. The addition of ZrO₂ leads to a decrease in the crystallization temperature of LiPO₃ glass. It was found that the conductivity behavior depends on the nature of the dispersed addition. In the case of the Al₂O₃ addition, the increase in the electrical conductivity is observed. The ionic conductivity of the LiPO₃/10% Al₂O₃ composite reaches 5.8 × 10^?8 S/cm at room temperature. In contrast, the conductivity in the LiPO₃/ZrO₂ composite system decreases.     

On the mutual solubility in MMoO4-LnVO4 systems,where M = Ca,Cd, Sr,Ba, Pb,Ln = Y,Sc, Ce-Lu

Journal of Structural Chemistry - The factors determining the solubility in MMoO4(scheelite)-LnVO4(zircon) systems, where M = Ca, Cd, Sr, Ba, Pb, Ln = Y, Sc, La-Lu, are analyzed. It is shown that...     

Analysis of pair heterovalent substitutions in scheelite-type molybdates and tungstates

An analysis of the formation of solid solutions in MAO₄-(Me_0.5Ln_0.5)AO₄ systems, where Me = Li, Na, K; M = Ca, Sr, Ba, Pb, Cd; Ln = La-Gd, Y, Bi; A = Mo, W, is performed in the approximation of regular solutions. Equations that make it possible to determine the temperature of the transition of limited solid solutions to unlimited ones at heterovalent substitutions M²⁺ ↔ (Me_0.5⁺Ln_0.5³⁺) are obtained.     

Quantum-chemical features of Ln—O interatomic interactions in LnNbxOy (Ln=La, Ce, Pr, Nd, Pm, Sm, Eu) systems

Properties of the lanthanide—oxygen bonds in lanthanide niobates LnNb₇O₁₂(Ln=La, Ce, Pr, Nd, Pm, Sm, Eu) have been studied using the ab initio cluster X _α discrete variational method with two different basis sets of molecular orbitals. It has been found that the structural instability of lanthanides LnNb₇O₁₂ (Ln=Nd, Sm) observed in experiments is due to the combined effect of decrease in the stability of [LnO₈] cluster and increase in quantum-mechanical Ln—O repulsion when the minimum near neodymium (in the first model of the basis set of molecular orbitals) or praseodymium (in the second model of the basis set of molecular orbitals) atoms is passed.     

Study of the structural stability of LnNbxOy systems (Ln = La, Ce, Pr, Nd, Pm, Sm, Eu) by the Xα method of discrete variation

The electronic structure and Ln-O (Ln = La, Ce, Pr, Nd, Pm, Sm, Eu) bonding parameters have been calculated by the X _α method of discrete variation taking into account the real structure of LaNb₇O₁₂ oxoniobate. It is shown that the experimentally observed tendencies in the change in the oxoniobate stability correlate with the decrease in the average electron-proton binding energy of LnO₈ clusters and enhanced repulsion between Ln and O orbitals to the end of the lanthanide series. Original Russian Text ? E.I. Yurieva, O.G. Reznitskikh, V.G. Bamburov, 2009, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73, No. 7, pp. 1066–1068.