Thermoelectric material including coating layers, method of preparing the thermoelectric material, and thermoelectric device including the thermoelectric material

摘要

A thermoelectric material includes powders having a surface coated with an inorganic material. The thermoelectric material includes a thermoelectric semiconductor powder and a coating layer on an outer surface of the thermoelectric semiconductor powders.

主权项

1. A thermoelectric material comprising:
a thermoelectric semiconductor powder, wherein the thermoelectric semiconductor powder comprises a Bi—Te based thermoelectric semiconductor doped with Sb; and a coating layer on an outer surface of each particle of the thermoelectric semiconductor powder, wherein the coating layer comprises at least one ceramic material selected from the group consisting of aluminum oxide, MN and BN, wherein an average thickness of the coating layer is about 1 nm to about 10 nm and the average thickness of the coating layer is equal to or smaller than a mean free path of phonons of the thermoelectric semiconductor such that phonons are scattered by the coating layer, and wherein a thermal conductivity of the thermoelectric material is decreased as compared to a thermoelectric material comprising the same thermoelectric semiconductor powder without a coating layer on the outer surface of each particle.