Abstract
Switchable conductivity in elementary semi-conducting materials has a high potential for the design of diodes,transistors and energy conversion technolo-gies.However,the ability to utilize their physical properties is dependent on doping within the carrier density transition temperature.Single-crystal tellurium has a high Seebeck coefficient and intrinsic p-n-p conduction at room temperature and therefore,is not suitable for thermoelectric applications.We demonstrate that the addition of isovalent Se lowers the Fermi level to achieve a stable p-type conductivity with a high band degeneracy near the valence band.We observed shifts in the n-p transition temperature below the intrinsic conductivity at 470 K based on changes in stoichiom-etry and carrier concentration above 1017 cm-3.In addition,the high thermal conductivity is significantly reduced with the increase in Se alloying due to the mass and strain fluctuations.This results in a moder-ately high zT of 0.4 at 673 K.
维普
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