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排序方式: 共有139条查询结果,搜索用时 15 毫秒
1.
Solid solutions based on K3PO4 in systems K3 – 4x
E"
x
PO4 (E" = Si, Ti, Ge, Zr, Sn, Hf, Ce) are synthesized. The crystal structure, thermal behavior, and electroconduction of the synthesized solutions is studied. The narrowest single-phase regions take place in the systems where E" = Si, Ge (x 0.025), and the widest, in the system with Zr (x 0.125, at 700°C). Introducing Ti or Sn additives (x 0.05) and minimum quantities of Zr, Hf, or Ce (x = 0.025) into potassium orthophosphate leads to stabilization of highly-conductive -modification of K3PO4 at room temperature. Maximum values of potassium-cation conduction in all the systems studied correspond to regions of single-phase solid solutions based on K3PO4. The maximum electroconductivity (0.005 S cm–1 at 300°C, 0.1 S cm–1 at 700°C) and the smallest activation energies (32–35 kJ mol–1) take place in the systems with Zr and Hf. 相似文献
2.
Prilezhaeva E. N. Laba V. I. Snegotskii V. I. Shekhtman R. I. 《Russian Chemical Bulletin》1970,19(7):1507-1511
Russian Chemical Bulletin - 相似文献
3.
E. I. Burmakin S. S. Stroev G. Sh. Shekhtman B. D. Antonov 《Russian Journal of Electrochemistry》2003,39(9):1005-1007
Solid solutions Cs3 – 2x
M
x
PO4 (M = Ba, Sr, Ca, Mg) are synthesized and their thermal behavior and electroconductivity are examined. Adding elements of Subgroup IIA of the periodic table into cesium orthophosphate shifts the phase transition, which occurs in pure Cs3PO4 at 450–620°, towards lower temperatures and raises the cesium cation conductivity at low temperatures. The electroconductivity of a high-temperature modification of Cs3PO4 is weakly dependent on the presence and concentration of such additives, which points to structural disordering of the cesium sublattice. 相似文献
4.
5.
G. Sh. Shekhtman E. I. Burmakin N. B. Smirnov N. O. Esina 《Russian Journal of Electrochemistry》2002,38(5):549-553
In the sodium-orthophosphate-based solid solutions in Na3 – 2x
M
x
PO4 systems (M = Cd, Pb), the electroconduction is maximum near the upper concentration boundaries of the single-phase regions: x 0.4 for M = Cd and x 0.25 for M = Pb. The conductivity values at 300°C are 6.25 × 10–3 and 2.5 × 10–3 S/cm, respectively. The conduction of synthesized solid electrolytes has a co-cation nature. Their electric characteristics, inferior to those of the Na3PO4-based solid solutions obtained via heterovalent substitutions of another type, may be a manifestation of an effect similar to the polyalkali effect. 相似文献
6.
Solid electrolytes in the systems K3 – 3x
Me
x
PO4 (Me = Sc, Y, In, La, Nd, Gd, Tb) are synthesized. Their phase composition and the temperature and concentration dependences of their electroconductivity are studied. In all the systems there form solid solutions based on K3PO4, which have a high potassium cation conductance. The latter is due to the formation of potassium vacancies at substitutions 3K+ Me3+ and, at lower temperatures, to stabilization of a high-temperature -modification of potassium orthophosphate. The electroconductivity of synthesized solid solutions, which equals (4–7) × 10–3 and 10–1 S cm–1 at 300 and 700°C, is similar to that of solid electrolytes K3 – x
P1 – x
E
x
VIO4 and K3 – 4x
E
x
IVPO4. 相似文献
7.
8.
Shchelkanova Mariya S. Shekhtman Georgi Sh. Kalashnova Anastasia V. Reznitskikh Olga G. 《Journal of Solid State Electrochemistry》2018,22(9):2959-2964
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... 相似文献
9.
G. Sh. Shekhtman E. I. Burmakin B. D. Antonov 《Russian Journal of Electrochemistry》2013,49(7):693-697
The lithium-conducting solid electrolytes in the Li4 ? 2x Cd x GeO4 (0 ≤ x ≤ 0.6) system are synthesized. Their crystal structure and temperature and concentration dependences of conductivity are studied. The specimens with the highest conductivity have a γ-Li3PO4-derivative structure. The solid solutions with x = 0.15–0.25 are stable at the room temperature, whereas the specimens with x ≥ 0.3 decompose yielding Li2CdGeO4 below 310 ± 10°C. Li3.6Cd0.2GeO4 solid solution exhibits the highest conductivity (5.25 × 10?2 S cm?1 at 300°C). The factors, which affect the conductivity of synthesized solid electrolytes, are considered. 相似文献
10.
E. I. Lakhno E. I. Burmakin I. V. Korzun G. Sh. Shekhtman 《Russian Journal of Electrochemistry》2013,49(1):38-44
Solid solutions based on rubidium monogallate RbGaO2 with a general formula Rb2?2x Ga2?x A x O4 (A = P, V, Nb, and Ta) are synthesized. Their crystal structure and temperature and concentration dependences of conductivity are studied. The highest rubidium-cationic conductivity is (1.8–3.9) × 10?3 S cm?1 at 400°C and (1.4–2.1) × 10?2 S cm?1 at 700°C. These results are compared with the data for rubidium monogallate doped with four-charged cations and solid solutions based on RbAlO2. 相似文献