Photon treatment effect on the surface and figure of merit of thermoelectric material Bi2Te3−xSex

Abstract

The phase composition, structure, morphology, and thermal conductivity of Bi 2 Te 3−x Se x-based semiconductor solid solution after photon treatment (PT) were studied by X-ray diffractometry, SEM, TEM, and the laser flash techniques. It was revealed that PT leads to recrystallization of the subsurface layers of the solid solution with the formation of a heterogeneous nanocrystalline structure. The thermoelectric figure of merit of the semiconductor Bi 2 Te 3−x Se x (n-type) solid solution increases after PT due to modification of the surface layers. This is due to the decrease of the thermal conductivity of the studied material after PT.

Enhanced mechanism of thermoelectric performance of Bi2Se3 using density functional theory

“…The narrow-band gap (0.3 eV) semiconductor such as Bi 2 Se 3 has been recognized as an outstanding thermoelectric material [4][5][6]. Thermoelectric material's unique properties is that it can convert waste heat to electrical energy directly [7,8]. It has contributed to the development of many applications such as waste heat recovery, humidity sensors, solid-state generators and radiation sensors [9,10].…”