Electrophysical properties of the Bi2-xSe3-x x SmSe alloys as thermoelectric converter of n-type

Abstract

The paper presents the research of the electrophysical properties of the Bi2Se3-based alloys containing 0.5 – 5.0 mol. %SmSe at 27 – 110°C. The as-cast samples are synthesized by the ampoule method. The thermoelectric Q-factor of these alloys is determined according to the a2’a value. All the investigated alloy samples are semiconductive. When the SmSe content increases to 1.5 mol. %, inclusive, the decrease in resistance and the increase in the thermoelectric power are registered at indoor temperature. The a2’a values for the samples of this range composition are commeasurable. The increase in the temperature does not result in the change of the values of electrical conductivity and thermoelectric power in the sample containing 98.5 mol. % Bi2Se3. The increase in the SmSe content from 2 to 5 mol. % in the samples results in natural decrease in the a2'a value, that correlates with the second phase occurrence in the samples. The microhardness of the samples naturally increases from about 500 to 750 MPa when the SmSe content increases from 0.5 to 5 mol. %. The value of the SmSe solubility in Bi2Se3 under the standard conditions (25 °C) is 1.5 mol.% SmSe.

Представлены результаты изучения электрофизических свойств в интервале от 27 до 110°C сплавов на основе Bi2Se3 с содержанием SmSe от 0,5 до 5 мол. %. Образцы синтезированы ампульным методом в литом состоянии. По величине a2*σ определяли величину термоэлектрической добротности данных сплавов. Все изученные образцы сплавов имеют полупроводниковый характер электропроводности.