Surface conductivity and bulk thermoelectric properties of thermoelements on the basis of extruded samples of Bi0.5Sb1.5Te3 and Bi2Te2.7Se0.3 solid solutions

Surface conductivity of the thermoelements on a basis of the extruded samples of Bi0.5Sb1.5Te3 and Bi2Te2.7Se0.3 solid solutions and influence of the distorted surface layer, arising at manufacturing thermoelements on their bulk thermoelectric properties have been investigated over 77 - 470 K temperature range. It is found that thermoelectrical efficiency of thermoelements after treatment of a surface increases by 10-20%. The obtained results are explained by creating of the distorted layer of similar to 20 mum thickness on a surface of thermoelements in the course of their manufacturing.