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1.
A. R. Shaikhlislamova N. A. Zhuravlev A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2010,55(1):18-22
H3 − 2x
Nb
x
M2 − x
(PO4)3 (M = In, Fe) acid phosphates have been obtained by ion exchange from their lithium forms and X-ray powder diffraction, impedance
measurements, and 7Li and 1H NMR spectroscopy. The parameters of the hexagonal unit cell of the proton-exchanged forms differ only slightly from those
of the initial lithium compounds. According to 1H NMR data, the proton in the acid phosphates is not hydrated. The conductivity of the acid phosphates at high temperatures
depends weakly on their composition and is ∼1.7 × 10−7 S cm−1 at 620 K. The activation energy of conduction is 30–33 kJ/mol (430–770 K). 相似文献
2.
I. Yu. Pinus I. V. Arkhangel’skii N. A. Zhuravlev A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2009,54(8):1173-1176
Li1 +x
Ti2 − x
Ga
x
(PO4)3(x= 0−0.2) NASICON double phosphates are prepared and studied by high-temperature X-ray diffraction, 7Li NMR spectroscopy, impedance spectroscopy, and calorimetry. Doping with Ga3+ cations increases cation mobility in LiTi2(PO4)3. Ion conductivity, NMR spectroscopy, and calorimetry data imply the occurrence of a phase transition in LiTi2(PO4)3 and in products of partial gallium-for-titanium substitution.
Original Russian Text ? I.Yu. Pinus, I.V. Arkhangel’skii, N.A. Zhuravlev, A.B. Yaroslavtsev, 2009, published in Zhurnal Neorganicheskoi
Khimii, 2009, Vol. 54, No. 8, pp. 1235–1239. 相似文献
3.
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
4.
U. Ahmadu A. O. Musa S. A. Jonah N. Rabiu 《Journal of Thermal Analysis and Calorimetry》2010,101(1):175-179
Sodium zirconium phosphate (NZP) composition Na1−x
Li
x
Zr2(PO4)3, x = 0.00–0.75 has been synthesized by method of solid state reaction method from Na2CO3·H2O, Li2CO3, ZrO2, and NH4H2PO4, sintering at 1050–1250 °C for 8 h only in other to determine the effect on thermal properties, such as the phase formation
of the compound. The materials have been characterized by TGA and DTA thermal analysis methods from room temperature to 1000 °C.
It was observed that the increase in lithium content of the samples increased thermal stability of the samples and the DTA
peaks shifted towards higher temperatures with increase in lithium content. The thermal stability regions for all the sample
was observed to be from 640 °C. The sample with the highest lithium content, x = 0.75, exhibited the greatest thermal stability over the temperature range. 相似文献
5.
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
6.
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
7.
I. Yu. Kotova D. A. Belov S. Yu. Stefanovich 《Russian Journal of Inorganic Chemistry》2011,56(8):1189-1193
Ag1 − x
Mg1 − x
R1 + x
(MoO4)3 NASICON-like solid solutions, where R = Al or Sc and 0 ≤ x ≤ 0.5, were prepared; their crystal lattice parameters and thermal stabilities were determined. Silver-ion conductivity was
measured, and conductivity activation energy values were calculated for various temperature ranges. Above 400°C, Ag1 − x
Mg1 − x
R1 + x
(MoO4)3 phases have ionic conductivities comparable to the conductivities of sodium-ion and lithium-ion NASICON-like conductors.
The conductivity increases as the tervalent cation radius increases or the amount of mobile silver ions increases. 相似文献
8.
Hong Tang Xiao-Dong Guo Ben-He Zhong Heng Liu Yan Tang Rui Xu Long-Yan Li 《Journal of Solid State Electrochemistry》2012,16(4):1537-1543
Hybrid materials xLiFePO4·(1 − x)Li3V2(PO4)3 were synthesized by sol–gel method, with phenolic resin as carbon source and chelating agent, methylglycol as surfactant.
The crystal structure, morphology and electrochemical performance of the prepared samples were investigated by X-ray diffraction
(XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), galvanostatic charge–discharge test and particle size
analysis. The results show that LiFePO4 and Li3V2(PO4)3 co-exist in hybrid materials, but react in single phase. Compared with individual LiFePO4 and Li3V2(PO4)3 samples, hybrid materials have smaller particle size and more uniform grain distribution. This structure can facilitate Li
ions extraction and insertion, which greatly improves the electrochemical properties. The sample 0.7LiFePO4·0.3Li3V2(PO4)3 retains the advantages of LiFePO4 and Li3V2(PO4)3, obtaining an initial discharge capacity of 166 mA h/g at 0.1 C rate and 109 mA h/g at 20 C rate, with a capacity retention
rate of 73.3% and an excellent cycle stability. 相似文献
9.
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
10.
Phases of variable composition K1−x
A1−x
R1+x
(MoO4)3) (0 ≤ x ≤ 0.2–0.6), where A = Ni, Mg, Co, or Mn and R = Yb, Lu, or Sc, which crystallize in a NASICON-type structure (space group
R
c) were synthesized by solid-phase reactions. Their crystal parameters were calculated, and IR and Raman spectra described.
Original Russian Text ? N.M. Kozhevnikova, T.N. Khamaganova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol.
53, No. 5, pp. 864–865. 相似文献
11.
12.
T. N. Khamaganova 《Russian Journal of Inorganic Chemistry》2008,53(4):499-502
Phases of a variable composition in the Ba3−x
Sr
x
Y(BO3)3, system (0 < x < 3) have been investigated for the first time using the solid-phase reactions method. The formation of two series of solid
solutions crystallizing in different structural types have been established using X-ray diffraction (D-8 Advance diffractometer,
CuK
α radiation, graphite monochromator). Crystal characteristics of obtained phases have been determined.
Original Russian Text ? T.N. Khamaganova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 553–556. 相似文献
13.
Christie Thomas Cherian M. V. Reddy G. V. Subba Rao Chorng Haur Sow B. V. R. Chowdari 《Journal of Solid State Electrochemistry》2012,16(5):1823-1832
Sol–gel auto-combustion method is adopted to prepare solid solutions of nano-crystalline spinel oxides, (Ni1 − x
Zn
x
)Fe2O4 (0 ≤ x ≤ 1).The phases are characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy, selected
area electron diffraction, and Brunauer–Emmett–Teller surface area. The cubic lattice parameters, calculated by Rietveld refinement
of XRD data by taking in to account the cationic distribution and affinity of Zn ions to tetrahedral sites, show almost Vegard’s
law behavior. Galvanostatic cycling of the heat-treated electrodes of various compositions are carried in the voltage range
0.005–3 V vs. Li at 50 mAg−1 up to 50 cycles. Phases with high Zn content x ≥ 0.6 showed initial two-phase Li-intercalation in to the structure. Second-cycle discharge capacities above 1,000 mAh g−1 are observed for all x. However, drastic capacity fading occurs in all cases up to 10–15 cycles. The capacity fading between 10 and 50 cycles is
found to be greater than 52% for x ≤ 0.4 and for x = 0.8. For x = 0.6 and x = 1, the respective values are 40% and 18% and a capacity of 570 and 835 mAh g−1 is retained after 50 cycles. Cyclic voltammetry and ex situ transmission electron microscopy data elucidate the Li-cycling
mechanism involving conversion reaction and Li–Zn alloying–dealloying reactions. 相似文献
14.
L. N. Komissarova M. A. Ryumin V. V. Pukhkaya E. V. Samsonova Yu. V. Orlovskii 《Russian Journal of Inorganic Chemistry》2011,56(12):1943-1950
Al synthesized samples are isostructural and crystallize in the orthorhombic symmetry system, space group Ibca. Particles of the final product of ∼200 nm in size have been obtained. The introduction of the vanadate anion into the matrix
composition leads to the lowering of the symmetry of the Eu3+ environment and to the rise of the defect luminescence at 450–550 nm because of the unit cell distortion. The luminescence
of defects in terbium-europium-containing samples is determined by the sample surface area, which decreases on annealing.
The τ, W
0 and γ parameters of the luminescence kinetics of the samples have been determined. 相似文献
15.
N. M. Kozhevnikova 《Russian Journal of Applied Chemistry》2010,83(3):384-389
The synthesis conditions for variable-composition phase Na1−x
Co1−x
Fe1+x
(MoO4)3, 0 ≤ x ≤ 0.4, crystallizing in the nasicon structure type (R
$
\bar 3
$
\bar 3
c) were examined. For this phase, the crystallographic parameters were calculated, vibrational spectra were interpreted, and
temperature dependence of electrical conductivity, dielectric constant, and dielectric loss tangent were examined. 相似文献
16.
T. N. Khamaganova 《Russian Journal of Applied Chemistry》2008,81(7):1290-1292
The possibility of preparing two series of solid solutions in the system Ba3 − x
Sr
x
Er(BO3)3 (0 ≤ x ≤ 3.0), crystallizing in different structural types, was examined. Samples of the phases of variable composition were synthesized
by the method of solid-phase reactions, and their X-ray phase analysis was done. The X-ray diffraction characteristics of
the phases synthesized were determined.
Original Russian Text ? T.N. Khamaganova, 2008, published in Zhurnal Prikladnoi Khimii, 2008, Vol. 81, No. 7, pp. 1210–1212. 相似文献
17.
E. A. Shusharina P. E. Plyusnin S. P. Khranenko S. A. Gromilov 《Journal of Structural Chemistry》2011,52(1):125-132
Complex salts [Ir(NH3)5Cl]x[Rh(NH3)5Cl]1−x
MO4 (x = 0.5, 1; M = Mo, W) are synthesized and their thermal properties are studied. The crystal structures are determined for
[Ir(NH3)5Cl]WO4 and [Ir(NH3)5Cl]MoO4. In the structures, the ions are linked by N-H...O hydrogen bonds, the shortest ones being 2.868(2)–3.422(2) ?. and 2.860(4)–3.434(3)
?. respectively. The thermal properties of the complex salts are studied in the hydrogen atmosphere and in hydrogen-helium
mixtures. It is demonstrated that the final products are the mixtures of nanocrystalline powders of Ir and binary or ternary
solid solutions with the hcp lattice. 相似文献
18.
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
19.
Roman Zaremba Ute Ch. Rodewald Rolf-Dieter Hoffmann Rainer P?ttgen 《Monatshefte für Chemie / Chemical Monthly》2008,139(5):481-487
The rare earth-transition metal-indides RE
4IrIn (RE = Gd–Er) and the solid solutions RE
4
TIn1–x
Mg
x
(RE = Y, Gd; T = Rh, Ir) were prepared by arc-melting of the elements and subsequent annealing. The rare earth sesquioxides were used as
oxygen source for the suboxides RE
4IrInO0.25 (RE = Gd, Er). Single crystals of the indides were grown via slowly cooling of the samples and they were investigated via X-ray powder diffraction and single crystal diffractometer data: Gd4RhIn type, F
3m, a = 1372.3(6) pm for Gd4IrIn, a = 1365.3(6) pm for Tb4IrIn, a = 1356.7(4) pm for Dy4IrIn, a = 1353.9(4) pm for Ho4IrIn, a = 1344.1(4) pm for Er4IrIn, a = 1370.3(5) pm for Y4RhIn0.54Mg0.46, a = 1375.6(5) pm for Gd4IrIn0.55Mg0.45, a = 1373.0(3) pm for Gd4IrInO0.25, and a = 1345.1(4) pm for Er4IrInO0.25. The rhodium and iridium atoms have a trigonal prismatic rare earth coordination. Condensation of the RhRE
6 and IrRE
6 prisms leads to three-dimensional networks which leave voids that are filled by regular In4 or mixed In4–x
Mg
x
tetrahedra. The indium (magnesium) atoms have twelve nearest neighbors (3In(Mg) + 9RE) in icosahedral coordination. The rare earth atoms build up a three-dimensional, adamantane-like network of condensed, edge
and face-sharing octahedra. For Gd4IrInO0.25 and Er4IrInO0.25 the RE16 octahedra are filled with oxygen. The crystal chemical peculiarities of these rare earth rich compounds are discussed.
Correspondence: Rainer P?ttgen, Institut für Anorganische und Analytische Chemie, Westf?lische Wilhelms-Universit?t Münster,
Germany. 相似文献
20.
Oana Crina Bujor Stéphane Célérier Sylvette Brunet 《Journal of Sol-Gel Science and Technology》2010,54(2):220-231
Pure ceria-zirconia mixed oxides Ce
x
Zr1−x
O2 with high specific surface area were synthesized with a new epoxyde driven sol–gel route and characterized by thermal analysis,
X-ray diffraction studies and transmission electron microscopy. This sol–gel method is cheap and uses only a few steps. The
Ce
x
Zr1−x
O2 mixed oxides were obtained in the range of 0 ≤ x ≤ 1 (except for x = 0.8) and crystallised at 350 °C after decomposition of the gels. This temperature is very low in comparison with the other
methods. The studies of the influence of different synthesis parameters (concentration of the sol and decomposition temperature)
allowed us to determine the conditions to obtain the best homogeneity in the gel to avoid the formation of a mixture of phases
instead of mixed oxides. This approach leads to the synthesis of oxide with specific surface area above 100 m2 g−1. The elaboration of an ambigel could increase this value up to 195 m2 g−1 for x = 0.5. This sol–gel synthesis offers new perspectives for these oxides in several applications. Generally, these oxides are
difficult to obtain pure in large range of composition at low-temperature and with high specific surface area by other methods. 相似文献