Electrical resistivity and scattering mechanisms of GeTe-rich thermoelectric materials in the system GeTe-AgBiTe2

Electrical resistivity (80 to 800 K) of (GeTe)(1-x)(AgBiTe2)(x) solid solutions with 0.02 less than or equal to x less than or equal to 0.20 (bulk) and x = 0.03; 0.05. 0.10; 0.15. 0.20 (hot-pressed) samples is investigated. Information about the scattering mechanisms in the system is obtained bi analysis of the experimental data of electrical resistivity. From the results it is seen that the resistivity is determined mainly by scattering on acoustic phonons (rho(ac)) and increases nearly linearly with temperature. Up to temperatures of about 250 K the resistivity due to defects (rho(def)) decreases and above 250 K it is almost constant.