THERMODYNAMIC PROPERTIES OF SOLID SOLUTIONS IN THE Cu8GeS6-Ag8GeS6 SYSTEM

  • Isfendiyar Jalal Alverdiyev Cand. Sci. (Chem.), Accociate Professor of Ganja State University; e-mail:  ialverdiyev@mail.ru
  • Vusala Abbasova postgraduate student of Ganja State University, e-mail: _samira@mail.ru
  • Yusif Amiraly Yusibov Dr. Sci. (Chem.), Full Professor, Rector of Ganja State University; e-mail: babanlymb@gmail.com
  • Mahammad Baba Babanly Dr. Sci. (Chem.), Full Professor, Deputy-Directors of Institute of Catalysis and Inorganic Chemistry (ICICh); e-mail: babanlymb@gmail.com
Keywords: Cu8GeS6 - Ag8GeS6 system, solid solutions, EMF method, Cu4RbCl3I2 solid electrolyte, thermodynamic properties

Abstract

The system Cu8GeS6-Ag8GeS6 was studied by electromotive force measurements of the

(−)Cu(sol.)|Cu4RbCl3I2(sol.)|(Cu in alloys)(sol.)(+)(1)(1)(−)Cu(sol.)|Cu4RbCl3I2(sol.)|(Cu in alloys)(sol.)(+)

concentration chains within 300÷380 К temperature interval. In these chains, solid-state superionic conductor Cu4RbCl3I2 was used as the electrolyte. This compound possesses high ionic conductivity (0.5 Om-1·sm-1) on Cu+ cations at a room temperature. The metallic copper was used as a left (negative) electrode and equilibrium alloys of the studied system were served as right (positive) electrodes. The formation of wide areas of solid solutions based on Cu8GeS6 (α-phase, 60 mol.%) and Ag8GeS6 (β-phase, 23 mol.%) starting compounds is defined. Based on EMF measurements, the linear equations of temperature dependences EMF were obtained and presented in the following form

E=a+bT±t[S2En+S2b(Ti−T¯¯¯¯)2]1/2(2)(2)E=a+bT±t[SE2n+Sb2(Ti−T¯)2]1/2

where n is the number of pairs of E and T values; S2E and S2b are the error variances of the EMF readings and b coefficient, respectively.

The partial molar thermodynamic functions of copper in alloys were calculated based on the results of the EMF measurements.

Analysis of the concentration dependences of the partial molar functions of copper showed that the within homogeneity areas of α and β-phase with a decrease of the copper content the partial entropy increases monotonically, while the partial enthalpy and Gibbs free energy decrease. At the interfaces of α- and β-phases with two-phase α + β field, there are abrupt changes in the partial entropy and enthalpy. All partial molar functions of copper are constant in the α+β two-phase area, which is related with the constancy of compositions of coexisting phases.

Keywords: Cu8GeS6 - Ag8GeS6 system, solid solutions, EMF method, Cu4RbCl3I2 solid electrolyte, thermodynamic properties

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Author Biography

Isfendiyar Jalal Alverdiyev, Cand. Sci. (Chem.), Accociate Professor of Ganja State University; e-mail:  ialverdiyev@mail.ru

 

 

References

1. Babanly M. B., Yusibov Yu. A., Abishev V. T. Ternary Chalcogenides Based on Copper and Silver. Baku: BSU Publ., 1993, 342 p. (in Russian)
2. Applications of Chalcogenides: S, Se, and Te / Ed. by Ahluwalia G.K. Springer. 2016, 461 p.
3. Ivanov-Shits A. K., Murin I. V. Solid State Ionica. Vol. 1. S.-Petersburg University Press Publ., 2000, 616 p. (in Russian)
4. Lin Li, Yuan Liu, Jiyan Dai. J. Mater. Chem. C, 2016, vol. 4, pp. 5806-5813. DOI: 10.1039/C6TC00810K
5. Alieva Z. M., Bagheri S. M., Alverdiev I. Dzh, Yusibov Yu. A., Babanly M. B. Inorganic Materials, 2014, vol. 50, no. 10, pp. 981–986. DOI: 10.1134/S002016851410001X
6. Aliyeva Z. M., Bagheri S. M., Aliev Z. S., Alverdiyev I. J., Yusibov Yu. A. Babanly M. B. J. Alloys Compd., 2014, vol. 611, pp. 395–400. http://dx.doi.org/10.1016/j.jallcom.2014.05.112
7. Alverdiyev I. J., Abbasova V. A., Gahramanova A. S., Yusibov Y. A., Babanly M. B. “XV International Conference on Physics and Technology of Thin Films and Nanosystems (ICPTTFN-XV)”, Ivano-Frankivsk, Ukraine, 2015, p. 337.
8. Alverdiyev I. J., Aliev Z. S., Bagheri S. M., Mashadiyeva L. F., Yusibov Y. A., Babanly M. B. J. Alloys Compd., 2017, vol. 691, pp. 255-262. http://dx.doi.org/10.1016/j.jallcom.2016.08.251
9. Bagheri S. M., Imamaliyeva S. Z., Mashadiyeva L. F., Babanly M. B. International Journal of Advanced Scientific and Technical Research., 2014, iss. 4(2), pp. 291-296
10. Gorochov O. Bull. Soc. Chim. Fr., 1968, no. 6, рр. 2263–2275.
11. Babanly M. B., Yusibov Yu. A. Electrochemical Methods in the Thermodynamics of Inorganic Systems. Baku, ELM Publ., 2011, 306 p. (in Russian)
12. Prince A. In: Ternary Alloys. vol. 2, VCH, 1988, рp. 196-202.
Published
2017-11-06
How to Cite
Alverdiyev, I. J., Abbasova, V., Yusibov, Y. A., & Babanly, M. B. (2017). THERMODYNAMIC PROPERTIES OF SOLID SOLUTIONS IN THE Cu8GeS6-Ag8GeS6 SYSTEM. Kondensirovannye Sredy I Mezhfaznye Granitsy = Condensed Matter and Interphases, 19(1), 22-26. https://doi.org/10.17308/kcmf.2017.19/172
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