Semiconductor Physics, Quantum Electronics & Optoelectronics, 24 (2), P. 131-138 (2021).
Influence of cation substitution on electrical conductivity of microcrystalline ceramics based on (Cu1-xAgx)7GeSe5I solid solutions
1Uzhhorod National University, 46, Pidgirna str., 88000 Uzhhorod, Ukraine Abstract.
Ceramic samples based on the microcrystalline powders (Cu1–хAgx)7GeSe5I (x = 0, 0.25, 0.5, 0.75, 1) were prepared by pressing them at the pressure close to 400 MPa and
subsequent annealing at 873 K for 36 hours. Using the microstructural analysis, the average size of microcrystallites of these samples was determined. Investigation of
electrical conductivity of ceramics based on (Cu1 хAgx)7GeSe5I solid solutions was carried out using the method of impedance spectroscopy in the frequency range from 10 Hz
to 3×105 Hz and within the temperature range 293...383 K. Analysis of the Nyquist plots allowed determining the contributions of ionic and electronic components to the total
electrical conductivity. The temperature dependence of ionic and electronic conductivity in Arrhenius coordinates is linear, which indicates their thermoactivation character.
The compositional behaviour of ionic and electronic conductivity, as well as their activation energies have been studied.
Their nonlinear character can be explained by the complex process of recrystallization and Cu+ ↔ Ag+ cation substitution within the cationic sublattice.
Keywords: argyrodite, superionic conductor, solid solution, ceramic, impedance spectroscopy. This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.
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