Investigation of Thermoelectric Properties of Thallium Bismuth Diselenide Crystals

Abstract

Thermoelectric materials, which can be used in high-efficiency cooling and refrigeration, as well as energy scavenging, sensing, and thermo-power systems, can help to solve the global energy issue by providing a long-term energy solution. Our study sheds light on the thermoelectric power measurements of thallium bismuth diselenide crystals. A modified Bridgman technique was used to make TlBiSe₂ crystals. TlBiSe₂ crystals are particularly engaging in the quest for more effective thermoelectric materials that can change thermal energy to electrical energy and vice versa. The properties of thermal transport were studied. Thermoelectric power measurements were performed at temperatures ranging from 211 to 504 K. Based on these measurements, the conductivity of the crystals was determined to be n-type. The mobilities of the charge carriers, i.e., holes and electrons, were calculated to be 0.0115 cm²/(V s) and 0.0229 cm²/(V s), respectively. The effective masses of the majority and minority carriers were determined to be  4.3 x 10^-33 kg and 1.6 x 10^-31 kg, respectively. In addition, the relaxation times, diffusion coefficients, and diffusion lengths of both majority and minority carriers were checked. All the obtained parameters revealed that this semiconducting compound can be used in the fields of energy conversion, semiconducting devices, and electronic engineering.