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2022, №1 “Pedagogik mahorat” Ilmiy-nazariy va metodik jurnal
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Bog'liq pedagogik mahorat 2022 1Key words: complex oxides of antimony, pyrochlore-type structure, phase formation, space group Fd-
3m, solid-phase reaction.
Piroxlorin tipidagi tizimga k va Na ionlari Me
2
CO
3
- Sb
2
O
3
- WO
3
kiritilganda faza hosil boʻlish
jarayonlari boʻlib, unda ion oʻtkazuvchanlik xossalari oʻrganilgan. Olingan fazalarda Fd3m fazoviy
simmetriya guruhining nuqtaviy sistemasida ionlarning taqsimlanishi amalga oshirildi.
Kalit soʻzlar: antimonning murakkab oksidlari, piroklor tipidagi tuzilish, faza hosil boʻlishi, FD-3m
kosmik guruhi, qattiq fazali reaksiya.
Процессы фазообразования при введении ионов K и Na в систему пирохлорного типа Me
2
CO
3
-
Sb
2
O
3
- WO
3
, в которой были изучены свойства ионной проницаемости. В полученных фазах было
выполнено распределение ионов в системе точек группы пространственной симметрии Fd3m.
Ключевые слова: комплексные оксиды сурьмы, структура пирохлорного типа,
фазообразование, пространственная группа Fd-3m, твердофазная реакция.
Solid electrolytes with ionic conductivity for potassium cations are of interest for use in various
energy systems. However, unlike sodium solid electrolytes, relatively little is known about solid potassium
conductors; therefore, the search for new potassium super ion conductors remains relevant. The synthesis of
new materials with high ion permeability allows the creation of various electrochemical devices based on
them, including sensors, current sources, fuel cells and more. Compounds based on pyrochlorine-type
complex driving oxides are of particular importance because they are good ion conductors and ion
exchangers [1-6]. These compounds can be obtained by solid phase synthesis in a system containing
Me
2
CO
3
-Sb
2
O
3
-WO
3
(where Me = K, Na) [7-14].
However, the formation and stability of the phases obtained in this system have not yet been studied,
and the concentration interval for the synthesis of pyrochlor-type phases has not been determined.
In this regard, the purpose of this work was to study the processes of phase formation in the system
Me
2
CO
3
-Sb
2
O
3
-WO
3
(where Me = K, Na), to determine the composition and structure of the formed phases.
Trivalent antimony and hexavalent tungsten powder oxides, chemically pure potassium and sodium
carbonates were obtained as starting reagents. Sample synthesis was performed using a well-known method
[15-18]. The mixtures were prepared with different ratios of (1-х)K
2
CO
3
-хNa
2
CO
3
-Sb
2
O
3
-WO
3
reagents, and
the molar ratio of the components of the mixture x varied by 0.1 steps in the concentration range 0≤x≤1.0
(Table 1). After the samples were thoroughly ground with a thief, they underwent two-stage curing in air at a
temperature of 673 K and 1170 K. At a temperature of 1170 K, the samples are stored for 13 hour until a
continuous sample mass is obtained. The gross composition of the final products of solid phase synthesis was
calculated by the following reaction:
(1-х)K
2
CO
3
+хNa
2
CO
3
+Sb
2
O
3
+2WO
3
+0,5О
2
=2Na
X
K
1-x
WSbO
6
+2CO
2
(1), where 0≤x≤1.0 (Table 1).
It has been hypothesized that solid phase synthesis will result in the complete decomposition of
potassium and sodium carbonates and the oxidation of the trivalent lead to the pentavalent state.
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