Prospects for the practical use of the Kaminskii thermovoltaic effect

Abstract

The Kaminskii thermovoltaic effect, which is one of the new principles of converting thermal energy into electrical energy, is considered in the article. Samples of the rare-earth semiconductor samarium monosulfide (SmS), located in a uniform temperature field without any temperature gradient, generated an electromotive force (emf). The nature of the effect is associated with the concentration gradient of Sm impurity atoms in the sample, a combination of electronic and thermal processes at temperature about 200 °C, and the appearance of a concentration gradient of free electrons, which leads to the generation of emf. The following electrical characteristics of the effect were achieved on bulk samples: a 2.5 V emf in a pulsed mode with a pulse duration of 1.3 s and a 0.05 V emf in a continuous mode. The parameters of thermoelements based on the Kaminskii effect and based on the classical Seebeck thermoelectric effect were compared. The maximum values of the efficiency were 36 % and 10 %, respectively. The effect was observed on other semiconductors, however, its maximum values occur in SmS, which is explained by fundamental reasons related to the position of rare-earth elements in the periodic table. The thermovoltaic effect can be used for direct conversion of associated heat and utilization of waste heat as power sources for various devices.