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CHEMICAL PROBLEMS 2020 no. 1 (18) ISSN 2221-8688
UDC 546.87.546.657.546.31.
STUDY OF 3Bi2O3-5B2O3-Nd2O3-3B2O3 SYSTEM AND DEPENDENCE OF ELECTROPHYSICAL AND HEAT PROPERTIES OF OBTAINED ALLOYS ON THE
COMPOSITION
S.I. Bananyarli, Sh.S. Ismayilov, R.N. Gasimova, L.A. Khalilova
Acad. M. Nagiyev Institute of Catalysis and Inorganic Chemistry of the National Academy of Sciences of Azerbaijan H. Javid Ave.,113, AZ1143, Baku; e-mail: ishr_az.yahoo.com
Received 14.09.2019
The 3Bi2O3'5B2O3-Nd2O3 -3B2O3 system was studied using DTA, XRD, and electrical conductivity and heat properties measured. A new ternary compound was revealed in the system. Formation of a new compound expands an area of glass formation towards non-glass forming boundary binary compounds. It found that obtained materials possess semiconductor properties as distinct from initial 3Bi2O3-5B2O3, M2O3 3B2O3
Keywords: electric resistance, system, dielectric loss, phonons, dependence, frequency. DOI: 10.32737/2221-8688-2020-1-106-112
Introduction
Materials based on boric oxide are of a great practical importance. High dielectric borate glasses are widely used in different fields of technology (microelectronics) as high melting coatings which provide isolation of main operating materials from external influence. Laser borate crystals which are used in microelectronics are very important materials [1-6].
Composition of studied alloys consists of binary-, ternary-, tetra- and sometimes multicomponent mixtures. Production of new materials and improvement of their properties are possible by studying phase diagrams of multicomponent systems. Phase diagrams are closely connected with composition-property diagrams.
Earlier, we studied phase equilibriua and some physical properties of the BaO2B2O3-La2O3 2B2O3, BaO-La2O3-2B2O3,2B2O3-3SiO2-Bi2O3-B2O3, 2Bi2O3 -B2O3- 2Bi2O3 -3GeO2 and 3Bi2O3-5B2O3 - Nd2O3-3B2O3and systems to establish areas of glass formation therein [7-10]. From this point of view, the data on studying
Bi2O3-B2O3-Nd2O3 triple system, the research of internal section in the triple system by physical-chemical methods, the border of Bi2O3-B2O3-Nd2O3 triple system - binary systems Bi2O3-B2O3 Nd2O3- Bi2O3 and Nd2O3- B2O3 are less known in literature sources [11-15].
It is known that 5 compounds are generated in Bi2O3-B2O3 system: Bi2O3-3B2O3 (melting temp. (981K), 3Bi2O3-5B2O3 (995K), Bi2O3-B2O3 (963K), 2Bi2O3-B2O3 (948K) and 3Bi2O3-B2O3(908K) [1,2].
It was determined that 3 compounds had been formed in Nd2O3- B2O3 system: Nd2O3-3B2O3 (1428K), Nd2O3-B2O3 (1885K), 3Nd2O3-B2O3 [3]. In Bi2O3-Nd2O3 system formation of solid solution and one compound at 1:1 ratio based on primary compounds are shown in literature source.
In the present work we continued physical-chemical research of 3Bi2O3'5B2O3-Nd2O3'3B2O3 system and gave analysis of values typical for some electro-physical parameters of alloys [9].
CHEMICAL PROBLEMS 2020 no. 1 (18)
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Samples were prepared from oxides (Bi2O3, Nd2O3) of elements and borate acid. Borate acid was decomposed at 723K:
723K
H3B03 ^^ B203 + H20 We used chemically pure reagents in the synthesis of samples in the research work. Synthesis was conducted at 1273^1373K8-10 hours in platinum crucibles. The compositions (those with high concentration of Nd2O3) with high melting temperature were synthesized by solid phase synthesis method 40-50 hours at 1273K in platinum crucibles [8-9].
Synthesized samples were studied by differential-thermal analysis (DTA), X-ray phase analysis methods. Differential thermal
al part
analysis (DTA) was performed on a derivatograph with a Pt-Pt / Rh thermocouple in platinum crucibles with a heating rate of 10°/min.X-ray phase analysis was conducted on diffractometer «D 2Phazer» (CuKa ray, Ni -filter).
According to the results of differential-thermal analysis we determined that softening temperature of synthesized glasses was in the range of 773^ 873K, melting temperature -973^ 1073K, and hardening temperature -943^1043K. Optimum crystallization condition for glasses was selected and crystallization process conducted at 923K 100 hours.
Results and discussion
On the basis of differential-thermal and X-ray phase analysis phase diagram of 3Bi2O3-5B2O3-Nd2O3-3B2O3 system was plotted (Fig. 1.) [9]. As is seen from diagram,
3Bi2O3'5B2O3-Nd2O3'3B2O3 system was quasi-binary, and formation of new one compound in the system determined.
Fig. 1. Phase diagram of the 3Bi2O3-5B2O3-Nd2O3-3B2O3 section.
The composition of the new compound conforms to 86 mol% 3Bi2O3-5B2O3 14mol% Nd2O3'3B2O3, it is glass-like, softening temperature is 773K, crystallization temperature
- 943K, melting temperature - 1113K.
We determined eutectics between new compound and primary oxides: e1= 93mol%, 3Bi2O3-5B2O3 - 7mol%, Nd2O3-3B2O3 and e2=
80mol%, 3Bi2O3-5B2O3 - 20 mol%, Nd2O3'3B2O3, melting temperature is 813^ 973K correspondingly.
Also, 10, 20, 30, 50 and 70 mol% Nd2O3'3B2O3 containing alloys of 3Bi2O3-5B2O3-Nd2O3-3B2O3 system were synthesized additionally. Some physical parameters of samples synthesized in the range of T=300^600K: composition dependence of electrical resistance (R), volt-ampere characterization (VACh), heat conductivity
coefficient (s) and heat resistance values were calculated and their diagrams drawn and analyzed.
Fig. 2 shows the dependence of the electrical resistance (R) on the composition at a room temperature. As is seen from Fig., when moving from primary substance (3Bi2O3'5B2O3) to 10 mol% of Nd2O3 oxide containing composition, R resistance dropped approximately by one order R= 8.5-1011 Ohm.
Fig. 2. Structural dependence of electric resistance (R) of the (3Bi2O3-5B2O3)100-x-(Nd2O3-3B2O3)x system T= 300K
Fig. 3. Temperature dependence of electric resistance
of (3Bi2O3-5B2O3)100-x-(Nd2O3-3B2O3)x N2 - x = 10 mol%; N4 - x = 20 mol%; N14 - x = 70 mol%
This reduction is explained by the formation of optimal maximum structure in the composition. Increase of Nd2O3'3B2O3 component up to 25mol% occurred due to the formation of additional dispersion center and value of electric resistance in 50:50mol% was maximum (9.8-1012 Ohm). In the system, this sample (50 mol %) was a material with maximum resistance. In following increase of the second component (Nd2O3'3B2O3) the value of electric resistance is reduced approximately to ~5-1010Ohm-sm.
We may come to the conclusion that alloys of (3Bi2O3-5B2O3)100-x- (Nd2O-3B2O3)x system pertained to high resistive active dielectric row.
Fig. 3 shows temperature dependences of electric resistances of x=10(N2); x=20(N4) and x=70(N14) mol% Nd2O3-3B2O3 sample from (3Bi2O3-5B2O3)100-x-(Nd2O3-3B2O3)x system alloys. Measurements were performed in the temperature range of T=300^680K. As is seen from the chart, in the temperature range of
T=300-460K and in x=20 and 70 mol% samples R(T) dependences were relatively stable and had values of R=8.5-109-8-1010ohm.
Fig. 4 shows the dependence of dielectric permittivity (s) and dielectric loss (tgô) of 30mol% (3BÎ2O3-5B2O3) + 70mol% -(Nd2O3-3B2O3) samples on space frequency. According to Fig. 4, at T = 300 K and a frequency of / = 10 Hz, the dielectric constant s '= 54, at f = 100 Hz, the s decreased to 40. In the range of /=103^105 Hz it is relatively stable within experimental error and in the course of further increase of space frequency (/>105 Hz) it decreased slightly. As for the value of dielectric loss, the situation is different: in the range of /=50^105 Hz it was tgô -const-6. But in the range of />105 Hz dielectric loss increased. The values of electric resistances and dielectric constants of this composition at T=300^460K and in /<105 Hz frequencies were relatively stable.
Fig. 4. The dependence of dielectric permittivity (s) (1) and dielectric loss (tgS) (2) of 30 mol% (3Bi2O3-5B2O3) + 70 mol% -(Nd2O3-3B2O3) sample on dielectric space frequency. T=300K.
Fig. 5 shows the volt-ampere characteristics (VACh) for the alloys of the composition (N2: x=10 mol% Nd2O3 -3B2O3 , N4 x=20 mol% u N14 x=70mol%). The measurements were carried out at a room temperature and electric field voltage in the range E = 0 ^ 450 V / cm. According to Fig. 5, the volt-ampere characteristic has a different shape. A sample
with composition x = 70 mol% in the range U = 0 ^ 150 V (in other words, at low voltage values), had a semiconductor property, its resistance at a room temperature is R -8.5 • 1010 Ohm, and in a wide temperature range (T = 300 ^ 460 K) it had dielectric properties, relatively low dielectric constant and at U=0-150V, its
volt-ampere characteristic corresponds to semiconductors.
Fig. 5. Volt-ampere characteristics (VACh) for alloys of the (3Bi2O3 •5B2O3)ioo-x - (Nd2O3 -3B2O3)x system. N2-x = 10 mol%; N4-x = 20 mol%; N14-x = 70 mol%
The temperature dependences of the thermal conductivity x and thermal resistance coefficient ro at compositions x = 30 and 50 mol% are also studied.As can be seen from figure 6, in the temperature range T = 300^420 K, the x values of the sample N1 are relatively stable and equal to xi~10.8 • 10-3 Vt / cm • K, while in sample N2, in the temperature range T = 300 ^ 500 K is relatively stable and equal to X2~12 • 10-3Vt / cm • K. With a further increase in temperature (T
>420K) in the sample N2-x = 30 mol%, the X2 value sharply decreases and at T = 620K, the X2~4 • 10-3Vt / cm • K, and vice versa for the sample N1-x~50 mol% , at T >420 K, the xi decreases very slightly and at T = 620K corresponds to xi = 5 • 10-3Vt / cm • K. To identify the defective nature of these samples, the dependence of the electrical resistance on temperature was analyzed (Fig.6).
Fig.6. Temperature dependences of thermal conductivity (1.2) and heat resistance (3.4) in the (3Bi2O3-5B2O3)i00-x - (Nd2O3-3B2O3)x system. 1 and 3 - x=50mol%; 2 and 4 - x=30 mol%
It was determined that in 300-480K temperature range heat resistance was relatively stable (w=const.). (Fig. 6). w increases in different rates in the further increase of temperature (in 30 and 50 mol% of samples). Non-linear change of w for these samples is related to not only the dispersion of phonons from point defect, vacant centers, but also phonon-phonon interactions. In other words, low values and change of heat-conductivity x and heat resistance win complex form were related to sharp increase of mixed dispersion
mechanism. In other compositions (10, 20 and 70mol% of Nd2O-3B2O3) similar processes occurred. But in these samples the change of x in temperature range was weak, it was relatively stable within experimental error.
It was determined from analyses of heat conductivity coefficient and other kinetic parameters that unlike relevant properties of dielectric materials the change of parameters proved closer to relevant properties of semiconducting materials.
Results of the complex study of the 3Bi2O3-5B2O3-Nd2O3-3B2O3 system are presented and formation of one ternary compound revealed in the system. Based on analyses of heat conductivity coefficient and other kinetic parameters, we determined that unlike dielectric properties of starting
components, parameters of intermediate alloys are close to properties of semiconductor materials.
The formation of a new compound increases the glass formation region towards non-glass-forming boundary binary components.
References
1. Goleus I. V., Shulga T.F. Calculation of the resistivity of silicate and borosilicate glasses as a function of their composition and temperature. Glass Physicsand Chemistry, 2010, vol.36, issue 5, pp. 575-578.
2. Pasinkov V.V., Sorokin. V.S. Materials of electronic technology. Moscow: Vishaya shkola Publ., 1999, p. 366.
3. Dembovskiy S.A. Chechetkina E.A. Glassformation. Moscow: Nauka Publ., 1990, p. 279.
4. Vinogradova N.N., Dmitruk L.N., Petrova O.B. Glass Transition and Crystallization of Glasses Based on Rare-Earth Borates. Glass Physics and Chemistry, 2004, vol. 30, issue1, pp.1-5.
5. Voronko Yu.K., Galaktionov S.S., Dmitru L.N. et al. Spectroscopic studies of glasses based on rare-earth borates. Glass Physics and Chemistry. 2006, vol. 32, issue 1, pp. 47-51.
6. Aliev O.A., Garayeva S.Kh. Phase formation in the Gd2Ge2O7 - B2O3 system. Chemical
Problems, 2014, vol. 12, no.3, pp. 264-266.
7. Bananyarly S.I., Kasumova R.N. Phase Relations in the BaO-2B2O3-La2O3-3B2O3 System. Inorg.Mater., 2003, vol. 39, issue 8, pp. 843-844. (In Russian).
8. Bananyarly S.I., Gasimova R.N., Ismayilov Sh.S., Khalilova L.A. Physical and chemical research of the system (2Bi2O3'B2O3)100-x -(2Bi2O3'3GeO2)x and study of electrophysical properties of obtained alloys. Chemical Problems, 2019, vol.17 no.3, pp. 429-434.
9. Bananyarli S.I, GasimovaR.N, ismayilov Sh.J., Khalilova L.A., Mehdiyeva i.F. 3Bi2O3-5B2O3 - Nd2O3-3B2O3 system and electrophysical properties of intermediate alloys. 21st Century Scientific Research Conference: Theory and Practice. 2018, Prague, Czech Republic, pp. 24-31.
10. Bananyarly S.I., Gasimova R.N., Ismayilov Sh.S. Temperature dependence of dielectric permittivity of glasses of 2Bi2O3'3SiO2-Bi2O3-B2O3 system. Chemical Problems. 2013, vol. 11, no.2, pp.185-189.
11. Palakhov F.Y. State diagram of systems of high-melting oxides. 1985, issue 5, chapter 1, p. 57.
12. Kargin Y.F., Yegorov A.V. Synthesis and characreristics of structure of Bi24B2Ö39 with structure of sillenite. Inorg.mater., 1998, vol. 34 no. 7, pp. 859-863 (In Russian).
13. Yegorisheva A.V., Skorikov V.M., Volodin V.D., Myslitskii O.E., KarginYu.F. Phase equilibria in the BaO- Bi2O3- B2O3systemal.
Russ.J.Inorg.chem., 2006, vol. 51, issue 12, pp.1956-1960.
14. Arsenyev P.A., Kovba A.M., Bagdasarov Kh.S. et al. Compounds of rare earth elements. Systems with oxides of elements of I-III groups. Moscow: Nauka Publ. 1983.
15. Hamidova Sh.F., Kuli-zade E.S., Novruzova F.A., Mehdiyeva S.A. Glass formation in the systems Bi2O3-B2O3-LmO3 (Ln - La, Nd, Sm, Yb, Y). Chemical Problems. 2015, vol.13, no. 2, pp.209-212.
3Bi2O3-5B2O3-Nd2O3-3B2O3 SÎSTEMÎNÎN T3DQÎQÎ V3 ALINAN 3RÎNTÎL3RÎN ELEKTROFÎZÎKÎ V3 ÎSTÎLÎK XASSS3L3RÎNÎN T3RKÎBD3N ASILILIGI
S.i. БэпэпуагЬ, §.S. ismayilov, R.N. Qasimova, L.d. Xdlilova
AMEA akademikM.Nagiyev adina Kataliz vd Qeyri-uzvi Kimya institutu AZ1143 Baki, H.Cavidpr.113; e-mail: ishr_az.yahoo.com
Bu mdqalddd DTA, RFA metodlarindan istifadd eddrdk 3Bi2Os-5B2Os - Nd2O^3B2O3 sistemi ôyrdnilmiç, elektrik vd istilik parametrldri ôlçulmuçdur. Sistemdd yeni uçlu birld^mdnin meydana gdlmdsi açkar edilmiçdir. Yeni birld^mdnin dmdld gdlmdsi $u$ddmdldgdlmd sahdsini $u$ddmdldgdtirmdydn ikili komponentldrd dogru geniçldndirir. Mudyydn edilmiçdir ki, parametrldrin ddyiçmdsi dielektrik madddldrin xususiyydtldrinddn daha çox yarimkeçirici materiallara uygundur. Açar sôzl^r: elekrik muqavimdti, sistem, dielektrik itkisi, fononlar, asililiq, tezlik.
ИЗ УЧЕНИЕ СИСТЕМЫ 3Bi2Or5B2O3-Nd2Or3B2O3 И ЗАВИСИМОСТИ ЭЛЕКТРОФИЗИЧЕСКИХ И ТЕПЛОВЫХ СВОЙСТВ ПОЛУЧЕННЫХ СПЛАВОВ ОТ СОСТАВА
С.И. Бананярлы, Ш.С. Исмайлов, Р.Н. Касумова, Л.А. Халилова
Институт Катализа и Неорганической Химии им. акад. М. Нагиева Национальной АН Азербайджана, AZ1143 Баку, пр.Г. Джавида,113; e-mail: ishr_az.yahoo.com
В статье представлены результаты исследования системы 3Bi2O3'5B2O3 - Nd2O^3B2O3 методами ДТА, РФА и измерения ее электрических и тепловых характеристик. В системе обнаружено образование нового тройного соединения. Образование нового соединения увеличивает область стеклообразования в сторону не образующих стекло пограничных двойных компонентов. Было установлено, что полученные материалы обладают полупроводниковыми свойствами в отличие от исходных 3Bi2O3'5B2O3, Nd2O3'3B2O3.
Ключевые слова: электрическое сопротивление, система, диэлектрические потери, фононы, частота.
