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1.
Information on the across-plane conductivity of films of solid-oxide electrolytes SrZr0.95Y0.05O3–δ and CaZr0.9Y0.1O3–δ deposited on ion-conducting supports is acquired by the impedance method. It is shown that the support/film interface and the intergrain boundaries considerably affect the across-plane charge transfer in the film. The effect of the crystallographic orientation of the YSZ support on the microstructure and conductivity of the CaZr0.9Y0.1O3–δ electrolyte film is demonstrated.  相似文献   

2.
The chemical potential of oxygen ΔμO relative to its standard state in the gas phase was calculated from the experimental dependences of the oxygen content in various polymorphic modifications of Ca0.9Pr0.1MnO3–δ on the partial pressure and temperature. The partial molar enthalpy \(\Delta {\overline H _O}\) and entropy \(\Delta {\overline S _O}\) of oxygen were obtained from the linear temperature dependences of ΔμO. Based on the ideal solution approximation, \(\Delta {\overline H _O}\) and \(\Delta {\overline S _O}\) were correlated with the enthalpies and entropies of the defect formation reactions, the concentrations of manganese cations, and the oxygen nonstoichiometry. The thermal excitation of Mn4+ cations was shown to substantially affect the thermodynamic functions of oxygen.  相似文献   

3.
CaZr0.9Y0.1O3–δ powders were synthesized by chemical solution methods: modified Pechini method and from solutions of inorganic salts in water and ethanol. The structure crystallizes into the orthorhombic type upon annealing at 1000°C for powders prepared by the Pechini method and from solution of salts in water. It was shown that CaZr0.9Y0.1O3–δ powders synthesized by various methods have different dispersities. The results obtained in a study of the granulometric composition by the sedimentation method and microscopic analysis enable fabrication of dense and mechanically strong electrolyte films and ceramics.  相似文献   

4.
In this study, the A-site-deficient ABO3 perovskites La0.9–x Sr0.1Ga0.8Mg0.2O3– with x=0.025, 0.05, 0.075, 0.1, and 0.2 were prepared by conventional solid state reactions. X-ray investigations were carried out in order to determine the influence of the A-site deficiencies on the structure. The electrical conductivities were measured as a function of both temperature and oxygen partial pressure in ranges 500–1000 °C and 0.2–10–6 atm, respectively. Only for small x values were single phases obtained. All compositions with A-site deficiencies exhibit a lower conductivity compared to the stoichiometric compound. It is shown by SEM micrographs that the sample morphology is changed by an A-site-deficient preparation as well. For A-site-deficient compositions, a reduction of the grain size is observed, most likely due to impurity inclusions in the grain boundaries.  相似文献   

5.
The complex Na3(NH4)2[Ir(SO3)2Cl4]·4H2O was examined with single crystal X-ray diffraction and IR spectroscopy. Crystal data: a = 7.3144(4) Å, b = 10.0698(5) Å, c = 12.3748(6) Å, β = 106.203(1)°, V = 875.26(8) Å3, space group P21/c, Z = 2, d calc = 2.547 g/cm3. In the complex anion two trans SO 3 2? groups are coordinated to iridium through the S atom. The splitting of O-H bending vibrations of crystallization water molecules and N-H ones of the ammonium cation is considered in the context of different types of interactions with the closest neighbors in the structure.  相似文献   

6.
Single crystals of Ba3[UO2(C2O4)2(NCS)]2 · 9H2O are synthesized and studied by X-ray diffraction. The crystals are orthorhombic, space group Fddd, Z = 16, and the unit cell parameters are a = 16.253(3) Å, b = 22.245(3) Å, c = 39.031(6) Å. The main crystal structural units are mononuclear complex groups [UO2(C2O4)2NCS]3? of the crystal-chemical family (AB 2 01 M1 (A = UO 2 2+ , B01 = C2O 4 2? , M1 = NCS?) of the uranyl complexes linked into a three-dimensional framework by electrostatic interactions and hydrogen bonds involving oxalate ions and water molecules.  相似文献   

7.
Processes were developed for manufacturing mixed magnetoelectric (ME) composites (100 − x) wt % PZTNB-1 + x wt % Ni0.9Co0.1Cu0.1Fe1.9O4 − δ using sol-gel processes to synthesize piezoelectric and magnetostrictive components; these processes provide composite ceramics having different connectivity types with the same composition. When PZTNB-1 prepared by the sol-gel process is used for manufacturing the composites, there is a deep one-way doping of the piezoelectric with ferrite constituents, and this doping considerably reduces the degree of tetragonal distortion of the perovskite unit cell to the point of disappearance. In contrast, when coarse-grained PZTNB-1 powder and a ferrite nanopowder prepared by the sol-gel process are used, undesirable doping is completely inhibited. This type of composite has the highest ME transduction efficiency, by two or more times exceeding the ME ceramics of the same composition manufactured by other processes.  相似文献   

8.
The structure of tri-μ2-disulfido-μ3-thiotris(diethyldithiocarbamato)-S,S′-triangle-trimolybdenum iodide [Mo33-S)(μ2-S2)3(Et2NCS2)3]I was determined. The compound was characterized by differential thermal analysis and IR, Raman, and X-ray electronic spectroscopy.  相似文献   

9.
A solvatothermal reaction of the octahedral cluster molybdenum complex (H3O)2[Mo63-Cl)8Cl6] · 6H2O with CaCl2 · 6H2O and OPPh3 in acetonitrile gave the known polymeric complex trans-[{Ca(OPPh3)4}{Mo63-Cl)8Cl6}]. However, a closer examination revealed that this system also produces a novel cluster complex, [Ca(OPPh3)5][Mo63-Cl)8Cl6] · OPPh3, which was isolated and characterized by X-ray diffraction.  相似文献   

10.
A new compound containing the tetraphenylphosphonium cation and the nickel(III) bisdicarbollyl anion, [(C6H5)4P][Ni(B9C2H11)2]·CCl4, was synthesized and investigated by XRD at room temperature (295 K). Crystal data: C29H42B18PCl4Ni, M = 816.69, monoclinic, space group P2/c; unit cell parameters a = 13.5873(6) Å, b = 7.1475(2) Å, c = 20.7829(8) Å, β = 94.4595(13)°, V = 2012.2(2) Å3, Z = 2, d calc = 1.348 g/cm3. The structure was solved by direct and Fourier methods and refined by the full-matrix least squares method in an anisotropic (isotropic for H) approximation to the final R 1 = 0.0466 for 3055 I hkl ≥ 2σ I of 23,655 reflections collected and 5618 independent I hkl (Bruker X8 APEX diffractometer, λMoK α).  相似文献   

11.
Compact CaZr0.9Y0.1O3–δ (CZY) film on a porous SrTi0.8Fe0.2O3–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.  相似文献   

12.
Single crystals of Cs[(UO2)2(C2O4)2(OH)] · H2O were synthesized and structurally studied using X-ray diffraction. The compound crystallizes in monoclinic space group P21/m, Z = 2, with the unit cell parameters a = 5.5032(4) Å, b = 13.5577(8) Å, c = 9.5859(8) Å, β = 97.012(3)°, V = 709.86(9) Å3, R = 0.0444. The main building units of crystals are [(UO2)2(C2O4)2(OH)]? layers of the A2K 2 02 M2 (A = UO 2 2+ , K02 = C2O 4 2? , and M2 = OH?) crystal-chemical family. Uranium-containing layers are linked into a three-dimensional framework via electrostatic interactions with outer-sphere cations and hydrogen bonds with water molecules.  相似文献   

13.
A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C.  相似文献   

14.
Single crystals of the Na4[Na2Cr2(C2O4)6] · 10H2O complex were synthesized for the first time. The structure of the complex was determined by X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system with the unit cell parameters a = 17.290(4) Å, b = 12.521(3) Å, c = 15.149(3) Å, β = 100.45(3)°, Z = 4, space group Cc. Anionic layers [NaCr(C2O4)3] 2n 4n? can be distinguished in the crystal structure of the complex. The Na+ cations and water molecules, involved in the formation of a hydrogen bond network, are located between the anionic layers.  相似文献   

15.
The compound [Co(NH3)6]2[W4Se4(CN)12]·8.5H2O was obtained by evaporating an aqueous ammonia solution of K6[W4Se4(CN)12]·6H2O and CoCl2·6H2O complexes. The starting Co(II) of CoCl2·6H2O transforms into [Co(NH3)6]3+ when exposed to air in a water-ammonia medium. Crystal data: triclinic crystal system, a = 10.7750(8) Å, b = 12.2843(9) Å, c = 19.6539(14) Å; α = 90.213(2)°, β = 99.910(2)°, γ = 114.737(1)°, V = 2319.1(3) Å3, space group , Z = 2, D x = 2.633 g/cm3.Original Russian Text Copyright © 2004 by I. V. Kalinina, Z. A. Starikova, F. M. Dolgushin, D. G. Samsonenko, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 905–908, September–October, 2004.  相似文献   

16.
Phase formation in the system Li2MoO4–MgMoO4–Sc2(MoO4)3 was studied by X-ray powder diffraction analysis and differential thermal analysis. Ternary molybdate LiMgSc(MoO4)3 was synthesized, which crystallizes in the triclinic system (space group P\(\bar 1\)). In the Li2Mg2(MoO4)3–Li3Sc(MoO4)3 section, a continuous solid solution in the rhombic system was found to form (space group Pnma).  相似文献   

17.
The single crystals of Rb2[(UO2)2(C2O4)2(SeO4)] · 1.33H2O were synthesized and studied by X-ray diffraction. The crystals are monoclinic, space group P21/m, Z= 2, the unit cell parameters: a = 5.6537(8), b = 18.736(3), c = 9.4535(15) Å, β = 98.440(5)°, V = 990.6(3) Å3, R 1 = 0.0506. The main structural units of the crystal are infinite layers of [(UO2)2(C2O4)2(SeO4)]2?, corresponding to the crystal chemical group A2K 2 02 B2 (A = UO 2 2+ , K02 = C2O 4 2? , B2 = SeO 4 2? ) of uranyl complexes. The uranium-containing layers are united into a three-dimensional framework through the electrostatic interactions with the outer-sphere rubidium ions and the hydrogen bonding system involving the outer-sphere water molecules.  相似文献   

18.
The crystal structure of a double complex salt of the composition [Au(en)2]2[Cu(C2O4)2]3·8H2O (en = ethylenediamine) at 150 K is determined by single crystal X-ray diffraction. The crystal data for C20H48Au2Cu3N8O32 are: a = 9.1761(3) Å, b = 16.9749(6) Å, c = 13.4475(5) Å, β = 104.333(1)°, V = 2029.43(12) Å3, P21/c space group, Z = 2, d x = 2.450 g/cm3. It is demonstrated that the thermal decomposition of the double complex salt in a helium or hydrogen atmosphere affords the solid solution Au0.4Cu0.6.  相似文献   

19.

Abstract  

Three novel lanthanide-organic frameworks: [Ln2(pyba)33-OH)22-OH)(H2O)] n (Ln = Er (1), Y (2), Dy (3) Hpyba = 4-pyridin-4-yl-benzoic acid) have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. Structure analysis shows that each {Ln43-OH)42-OH)2} cluster units interconnect to form 1-D chains, which are further linked by π–π interactions to make a 3-D supramolecular network structure. Furthermore, the IR, PXRD and TGA of compounds 13 were also studied.  相似文献   

20.
The described method for synthesis of proton-conducting ceramics BaZr0.9Y0.1O3 ? α at the temperature of 1850°C from mixture of barium carbonate and zirconium-yttrium hydroxides enabled to prepare high-density translucent specimens. According to powder diffraction data, the synthesized ceramics consists of single phase and has the cubic perovskite structure with the elementary cell parameter a = 0.42009 ± 0.00004 nm. The electrophysical properties of the synthesized ceramics were measured. The conductivity of such high-density specimens was shown to excel by an order of magnitude the conductivity of porous (80% relative density) material.  相似文献   

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