Thermoelectric properties of n-type Nb-doped Ag8SnSe6.

Electrical and thermoelectric (TE) properties for n-type Ag₈SnSe₆ and (Ag_1-xNb_x)₈SnSe₆ are investigated. Ag₈SnSe₆ has the thermoelectric figure of merit (ZT) close to 1.1 at 803K due to its intrinsic ultralow thermal conductivity ~0:3Wm^-1K^-1, relativelyμow resistivity ~0.01 X cm, and high Seebeck coefficient ~-200μV/K. The ZT for pure Ag₈SnSe₆ drops to 0.02 at room temperature due to itsμarge resistivity. Niobium doping increases the carrier concentration nearly 10 times and thus enhances its ZT to 0.11 at room temperature. Ag₈SnSe₆ is a promising n-type candidate of TE materials which needs further elaborations. [ABSTRACT FROM AUTHOR]