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1.
E. I. Burmakin E. I. Volegova G. Sh. Shekhtman 《Russian Journal of Electrochemistry》2010,46(11):1323-1327
New solid rubidium-conducting electrolytes based on rubidium monoferrite in the system of Rb2 − 2x
Fe2−x
V
x
O4 are synthesized and studied. It is found that introduction of V5+ ions causes a drastic decrease in the electronic conductivity component prevalent in pure RbFeO2 with a simultaneous increase in the ionic conductivity. The latter becomes predominant at an increase in the concentration
of vanadium. The optimum compositions of the studied electrolytes feature a very high cationic rubidium conductivity (∼1.8
× 10−2 S cm−1 at 200°C, more than 10−1 S cm−1 at 700°C). The results are compared with the data obtained earlier for similar systems based on RbGaO2 and RbAlO2. 相似文献
2.
A. S. Monaenkova A. A. Popova L. A. Tiflova M. L. Kovba 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(7):1085-1088
The enthalpies of reactions of Sm1 + x
Ba2 − x
Cu3O
y
substitution solid solutions (x = 0, 0.1, 0.2, 0.3, 0.7, and 0.8) with 1.07 N HCl were measured at 298.15 K in a hermetic isothermic-shell swinging calorimeter.
The results and the literature data were used to calculate the standard enthalpies of their formation from simple substances
and binary oxides (Δf
H
298.15o and Δox
H
298.15o). The dependence of the enthalpy of formation on the degree of samarium substitution for barium was obtained. 相似文献
3.
A. S. Monaenkova A. A. Popova L. A. Tiflova E. A. Gudilin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(8):1280-1284
The enthalpies of reactions of substitution solid solutions Pr1 + x
Ba2 − xCu3O
y
, where x = 0, 0.2, 0.4, 0.6, and 0.9, with 1.07 N HCl were measured at 298.15 K in a hermetic swinging isothermic-shell calorimeter.
The results and the literature data were used to calculate the standard enthalpies of formation of solid solutions from the
elements and oxides. The dependence of the enthalpy of solid solution formation on the degree of praseodymium substitution
for barium (x) was revealed. 相似文献
4.
V. D. Zhuravlev V. G. Zubkov A. P. Tyutyunnik Yu. A. Velikodnyi N. D. Koryakin 《Russian Journal of Inorganic Chemistry》2009,54(1):134-136
The phase compositions of theLaVO4-SrMoO4(1) and Sr2GeO4-SrMoO4 (2) binary systems, which bound the Sr2GeO4-LaVO4-SrMoO4 (3) ternary system, and the LaSr2(VO4)(GeO4)-Sr2GeO4+SrMoO4 section (4) of system 3 are studied at subsolidus temperatures. Systems 1 and 2 consist of a mixture of the initial compounds,
and the La1 − x
Sr2 + x
(GeO4)(V1 − x
Mo
x
O4) (where 0 ≤ x ≤ 0.4) region of substitutional solid solutions with a palmierite structure is formed in system 3. The unit cell parameters
of the solid solutions are determined. The distribution of the lanthanum and strontium cations over two positions of the cationic
sublattice is described.
Original Russian Text ? V.D. Zhuravlev, V.G. Zubkov, A.P. Tyutyunnik, Yu.A. Velikodnyi, N.D. Koryakin, 2009, published in
Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 1, pp. 135–137. 相似文献
5.
D. A. Medvedev E. V. Gorbova A. K. Demin B. D. Antonov 《Russian Journal of Electrochemistry》2011,47(12):1404-1410
In the present work, samples with the composition of BaCe0.77 − x Zr x Gd0.2Cu0.03O3 − δ (x = 0, 0.1…0.7, 0.77) were synthesized according to the standard solid state technique. The effect of zirconium oxide on the phase character, structure, and conductivity was studied using the methods of X-ray diffraction analysis, scanning electron microscopy, and four-probe method, accordingly. Stability of these materials in the flow of carbon dioxide was studied. The results show that introduction of zirconium oxide leads to preservation of a single-phase system (x ≤ 0.6), a decrease in the grain size, and an increase in stability in the CO2 atmosphere. 相似文献
6.
A. R. Shaikhlislamova I. A. Stenina A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2008,53(12):1829-1833
Synthesis and ionic conductivity of Li3−2x
Nb
x
Fe2−x
(PO4)3 complex phosphates were studied by X-ray powder diffraction and impedance spectroscopy. These phosphates are formed only
at 900–1000°C. Variations in their thermal expansivity and unit cell parameters induced by aliovalent doping were characterized.
The conductivity of these materials increases monotonically in the series Li0.5Nb1.25Fe0.75(PO4)3-LiNbFe(PO4)3 and Li1.2Nb0.9Fe1.1(PO4)3-Li3Fe2(PO4)3, which is explained by consecutive occupation of the Li(1) and Li(2) positions in their structures.
Original Russian Text ? A.R. Shaikhlislamova, I.A. Stenina, A.B. Yaroslavtsev, 2008, published in Zhurnal Neorganicheskoi
Khimii, 2008, Vol. 53, No. 12, pp. 1957–1962. 相似文献
7.
V. A. Ketsko E. N. Beresnev M. A. Kop’eva L. V. Elesina A. I. Baranchikov A. I. Stognii A. V. Trukhanov N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2010,55(3):427-429
This work demonstrates the possibility of preparing solid solutions in the (MgGa2O4)
x
(MgFe2O4)1 − x
system by pyrohydrolytic and solid-phase methods. It is shown that the products obtained have different specific surface
areas depending on the ratio between metal nitrates and citric acid. The composition dependence of the unit cell parameter
deviates considerably from the Vegard’s rule. The compounds obtained are found to be stable up to 300°C, which makes them
candidate materials for electronics. 相似文献
8.
T. I. Chupakhina N. I. Matskevich G. V. Bazuev N. A. Ovechkina V. R. Galakhov M. Raeckers M. Neumann 《Russian Journal of Inorganic Chemistry》2010,55(7):1002-1009
New perovskite oxide phases BaCe1 − x
In
x
O3 − x/2 (x = 0.1–0.8) (space group Pbnm) have been synthesized. The unit cell volume of the resulting solid solutions monotonically decreases with an increase in
the degree of substitution of indium for cerium due to the contraction of octahedra in perovskite blocks. The thermodynamic
stability of the compound BaCe0.75In0.25O2.875 was studied by the solution calorimetry method, and barium cerates were shown to be thermodynamically stable with respect
to binary oxides at room temperature. The structure of occupied and vacant states in BaCe1 − x
In
x
O3 − x/2 was determined on the basis of X-ray emission, absorption, and photoelectron spectra, and the energy gap was estimated at
∼2 eV. 相似文献
9.
A multicomponent system of complex refractory oxides of the composition Zn2 − x
(Zr
a
Sn
b
)1 − x
Fe2x
O4 (a + b = 1; a: b = 1: 5, 1: 4, 1: 3, 1: 2, 1: 1, 2: 1, 3: 1, 4: 1; x = 0−1.0; Δx = 0.05) was studied by X-ray diffraction. The samples were prepared from oxides of appropriate metals by low-temperature
plasma synthesis (hydrogen-oxygen flame). Two phases with wide homogeneity ranges were identified: α phase crystallized in
the crystal system of inverse cubic spinel and β phase with the structure of tetragonal spinel. The phase boundaries were
found. Structural data are presented for about 100 solid solutions. 相似文献
10.
11.
V. B. Balakireva A. V. Kuz’min V. P. Gorelov 《Russian Journal of Electrochemistry》2010,46(7):749-753
Proton and deuteron conductivities in the BaZr1 − x
Y
x
O3 − δ system (x = 0.02–0.2) are investigated experimentally over the temperature range 600–900°C in reducing H2/H2O and D2/D2O atmospheres with pH2O = pD2O = 3.15 kPa. 相似文献
12.
A. I. Pylinina I. I. Mikhalenko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(12):2109-2114
Characteristics of the catalytic activity in the dehydration of butanols of copper-containing sodium-zirconium-phosphates
(NZPs), in which Na+ ions substitute for Cu2+ ions are obtained. It was found that in the 100–370°C region, the action energy of the reaction falls upon the transition
through temperature T* ∼ 300°C, above which the electrophysical and crystallographic properties of phosphates change. The observed dependences
are explained by the center (which consists of copper with various positions in the phosphate network at T < T* and T > T*) taking part in the formation of carbonyl compounds. This indicates the presence of a ligand effect, i.e., to structural
sensitivity of the dehydration reaction in the case of Cu-NZP catalysts. 相似文献
13.
A. Yu. Suntsov I. A. Leonidov A. A. Markov M. V. Patrakeev Ya. N. Blinovskov V. L. Kozhevnikov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(5):832-838
The special features of the structure, electrophysical properties, and oxygen nonstoichiometry of new double perovskites PrBaCo2 − x
Cu
x
O5 + δ were studied. Within the homogeneity region with respect to copper 0 < x ≤ 1, solid solution samples had an orthorhombic structure (space group Pmmm) with the parameters a
p
× 2a
p
× 2a
p
, where a
p
≈ 3.8 ?. The oxygen nonstoichiometry of PrBaCo2 − x
Cu
x
O5 + δ changes as the copper content increases approximately as δ ≈ 0.85 − x/2. The content of oxygen was measured by coulometric titration over wide temperature and oxygen pressure ranges. The partial
thermodynamic functions of labile oxygen were calculated and the limits of the thermodynamic stability of the solid solution
were established.
Original Russian Text ? A.Yu. Suntsov, I.A. Leonidov, A.A. Markov, M.V. Patrakeev, Ya.N. Blinovskov, V.L. Kozhevnikov, 2009,
published in Zhurnal Fizicheskoi Khimii, 2009, Vol. 83, No. 5, pp. 954–960. 相似文献
14.
V. N. Krasil’nikov S. N. Shkerin O. I. Gyrdasova A. A. Korneva A. V. Nikonov A. S. Lipilin 《Russian Journal of Inorganic Chemistry》2011,56(7):999-1003
Highly dispersed single-phase powders described as La0.88Sr0.12Ga0.82Mg0.18O2.85 were prepared using a method based on the principles of self-propagating high-temperature synthesis (SHS). Lanthanum, strontium, gallium, and magnesium nitrates were used in the SHS as “oxidants”, and ethylene glycol was used as the reducing agent. The initial reaction mixture was liquid. According to X-ray diffraction and scanning electron microscopy data, the sample becomes a single phase after annealing of the primary SHS product at 1200°C, which is substantially lower than in other synthetic methods. Using so active powders (grain size of about 100–130 nm), it is possible to reduce the temperature of the final annealing of the ceramics to 1275°C, which gives rise to single-phase finely dispersed ceramics having specific properties. 相似文献
15.
16.
E. I. Burmakin G. Sh. Shekhtman B. D. Antonov 《Russian Journal of Electrochemistry》2011,47(4):453-456
New potassium-conducting solid electrolytes in the mixed ferrite-aluminate system K0.85Pb0.075(Fe1 − x
Al
x
)O2 are synthesized and studied. The electrolytes exhibit high ionic conductivity in the studied temperature range of 350 to
750°C (approximately 10−2 S/cm at 400°C and approximately 10−1 S/cm at 700°C). An increase in the conductivity with increasing concentration of iron in the specimens is a general tendency.
However, in a wide range of compositions (from x = 0.2 to x = 0.9), the conductivity only slightly depends on x. Possible reasons for the effect of Fe/Al ratio in the structure of solid electrolytes on their transport properties are discussed. 相似文献
17.
E. Yu. Pikalova A. A. Murashkina D. A. Medvedev 《Russian Journal of Electrochemistry》2011,47(6):681-689
CeO2-based solid solutions with a fluorite structure are promising materials as electrolytes of medium-temperature electrochemical
devices. This work presents the results of systematic studies of structural and electric properties and oxygen nonstoichiometry
of the Ce0.8(Sm1 − x
Ca
x
)0.2O2 − δ system in a wide range of concentrations of 0 < x < 1 performed in order to establish the causes affecting the system conductivity and its behavior in a reducing medium. It
is found that a single-phase solid solution of the fluorite type is formed in the whole concentration range. Parameters of
its lattice cells decrease linearly at an increase in the concentration of Ca2+. Conductivity in air grows when calcium is added due to a decrease in the grain boundary resistance. The maximum conductivity
in air was obtained for the composition of Ce0.8(Sm0.8Ca0.2)0.2O2 − δ and is 13.71 × 10−3 S/cm at 873 K. Studies of the dependence of conductivity of the partial pressure of oxygen showed that electron conductivity
is observed at a higher oxygen partial pressure at an increase in the temperature and calcium concentration. The critical
partial pressure of oxygen ( pO2 * )\left( {p_{O_2 }^* } \right) for the compositions of Ce0.8(Sm1 − x
Ca
x
)0.2O2 − δ with x = 0; 0.2, and 0.5 is 1.83 × 10−16, 1.73 × 10−13, and 3.63 × 10−13 atm at 1173 K, respectively, and 2.76 × 10−21, 5.05 × 10−18, and 1.31 × 10−18 atm at 1023 K. 相似文献
18.
I. Yu. Pinus I. A. Stenina A. I. Rebrov N. A. Zhuravlev A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2009,54(8):1177-1180
Li1 − x
Ti2 − x
Nb
x
(PO4)3 NASICON materials are prepared and studied by X-ray diffraction, 7Li and 31P NMR spectroscopy, and impedance spectroscopy. Vacancy mobility in Li1 − x
Ti2 − x
Nb
x
(PO4)3 is lower than interstitial lithium mobility. Nb5+ cations with low doping levels increase cation mobility in LiTi2(PO4)3.
Original Russian Text ? I.Yu. Pinus, I.A. Stenina, A.I. Rebrov, N.A. Zhuravlev, A.B. Yaroslavtsev, 2009, published in Zhurnal
Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1240–1244. 相似文献
19.
V. P. Gorelov V. B. Balakireva A. V. Kuz’min 《Russian Journal of Electrochemistry》2010,46(8):890-895
Ionic, proton, and oxygen conductivities are measured as functions of air humidity (pH2O = 0.04−3.57 kPa) in the BaZr1 − x
Y
x
O3 − α system (x = 0.02−0.15) over the temperature range 600–900°C. The important result is obtained that dissolved water vapor determines
not only proton transport, but also the overwhelming part of oxygen transport in BaZr1 − x
Y
x
O3 − α. 相似文献
20.
P. V. Anikina A. A. Markov M. V. Patrakeev I. A. Leonidov V. L. Kozhevnikov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(5):699-704
The influence of doping with niobium on the structure and oxygen nonstoichiometry of strontium ferrite SrFe1 − x
Nb
x
O3 − δ (x = 0.05, 0.1, 0.2, 0.3, and 0.4) was studied. The content of oxygen in the doped derivatives was determined by coulometric
titration as a function of temperature (650–950°C) and oxygen partial pressure in the gas phase (10−4−1 atm). The partial molar enthalpies Δ(x, δ) and entropies Δ(x, δ) of oxygen in SrFe1 − x
Nb
x
O3 − δ were calculated. An analysis of Δ(x, δ) dependences showed that the model of a random distribution of ions and vacancies over accessible sites in the oxygen
sublattice allowed the experimental data to be described satisfactorily. An increase in the partial enthalpy Δ(x, δ) as nonstoichiometry δ decreased was indicative of weak repulsive interactions between oxygen ions in the structure of
SrFe1 − x
Nb
x
O3 − δ.
Original Russian Text ? P.V. Anikina, A.A. Markov, M.V. Patrakeev, I.A. Leonidov, V.L. Kozhevnikov, 2009, published in Zhurnal
Fizicheskoi Khimii, 2009, Vol. 83, No. 5, pp. 811–817. 相似文献