Thermoelectric Properties of Ag-=SUB=-8-=/SUB=-Ge-=SUB=-1-x-=/SUB=-Mn-=SUB=-x-=/SUB=-Te-=SUB=-6-=/SUB=- Solid Solutions

Abstract

Ag 8 Ge 1-x Mn x Te 6 solid solutions with different manganese content (x=0, 0.05, 0.1, 0.2) were prepared by alloying and further pressing the powders under a pressure of 0.6 GPa. By the X-ray diffraction studies have shown that the introduction of manganese atoms leads to the compressibility of the Ag 8 GeTe 6 lattice. All p-type samples had high resistance below the transition at temperatures of 180-220 K. An increase in electrical conductivity in the range of 220-300 K was analyzed using the Mott ratio; at temperatures T>320 K, semiconductor behavior is observed in all compositions. The highest thermoelectric figure of merit ZT=0.7 at 550 K was obtained for a solid solution of the composition Ag 8 Ge 1-x Mn x Te 6 (x=0.05). Keywords: solid solution, Ag 8 Ge 1-x Mn x Te 6 , thermoelectric efficiency, amorphization, low thermal conductivity