Enhanced mid-temperature thermoelectric performance of textured SnSe polycrystals made of solvothermally synthesized powders

This work revealed that the thermoelectric properties of textured SnSe polycrystals, which are made of solvothermally synthesized powders with a preferred orientation grown along the (400) plane, can be enhanced, especially in the range of mid-temperatures. The electrical conductivity for the sintered sample is greatly improved in the whole measured temperature range, attributed to the high carrier concentration and unique mobility change. This results in a large power factor combined with the moderate Seebeck coefficient, especially in the range of 300-650 K, which exceeds 5 μW cm −1 K −2 at 423 K and even larger than 6 μW cm −1 K −2 at 521 K. Benefiting from the enhanced electrical conductivity and the low total thermal conductivity (