Thermoelectric properties and nonstoichiometry of GaGeTe
The polycrystalline samples of composition Ga1+xGe1-xTe (x = −0.03÷0.07) were synthesized from elements of 5N purity using solid state reaction. The products of synthesis were identified by X-ray diffraction. The samples for transport measurements were prepared using hot-pressing. They were characterized by the measurement of electric conductivity, Hall coefficient and Seebeck coefficient over a temperature range 80–450K and thermal conductivity over a temperature range 300-500 K. The samples show all p-type conductivity and we observe an increase in hole concentration with increasing x (content of Ga). We discuss the influence of Ga/Ge ratio on the phase purity of the samples and free carrier concentration. The investigation of thermoelectric properties shows that ZT parameter of these samples is too low at room temperature but increase distinctly with temperature.