Thermoelectric and magnetic properties of Cr-doped single crystal Bi2Se3 – Search for energy filtering

• Published in: Journal of solid state chemistry Vol. 258; pp. 768 - 775
• Main Authors: Cermak, P., Ruleova, P., Holy, V., Prokleska, J., Kucek, V., Palka, K., Benes, L., Drasar, C.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.02.2018
• Subjects: Energy filtering; Single crystal; Tetradymite; Thermoelectrics; Transition metal doping; Thermoelectrics; Energy filtering; Tetradymite; Single crystal; Transition metal doping
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2017.12.009

Thermoelectric effects are one of the promising ways to utilize waste heat. Novel approaches have appeared in recent decades aiming to enhance thermoelectric conversion. The theory of energy filtering of free carriers by inclusions is among the latest developed methods. Although the basic idea is clear, experimental evidence of this phenomenon is rare. Based on this concept, we searched suitable systems with stable structures showing energy filtering. Here, we report on the anomalous behavior of Cr-doped single-crystal Bi2Se3 that indicates energy filtering. The solubility of chromium in Bi2Se3 was studied, which is the key parameter in the formation process of inclusions. We present recent results on the effect of Cr-doping on the transport coefficients on a wide set of single crystalline samples. Magnetic measurements were used to corroborate the conclusions drawn from the transport and X-ray measurements. [Display omitted] •Solubility of chromium is close to x = 0.003 for Bi2−xCrxSe3 crystals.•Chromium doping varies mosaicity of Bi2Se3 single crystals.•Chromium induces extraordinary behavior of physical parameters in Bi2Se3 crystals.•Chromium doping seems to induce all forms of magnetism in Bi2Se3 crystals.