Year: 2016
Type: article
Abstract: A Bi2Te3–Sb2Te3 solid solution was prepared by mechanical alloying (MA) followed by hot pressing (HP). X-ray diffraction indicated that all samples which were removed at a depth below the surface of approximately 1 mm were single-phase and isotropic Bi2Te3–Sb2Te3 solid solution. Reduction of the phonon thermal conductivity as a result of the fine-grains caused by MA predominated over the solid-solution effect caused by melt growth. The Seebeck coefficient and electrical and thermal conductivities fluctuated between those for (Bi2Te3)0.15(Sb2Te3)0.85 and (Bi2Te3)0.2(Sb2Te3)0.8 at room temperature. A (Bi2Te3)0.15(Sb2Te3)0.85 solid solution with a dimensionless figure of merit ZT = 1.16 at 367 K was obtained by MA–HP. These results indicate that the maximum ZT of the Bi2Te3–Sb2Te3 solid solution obtained by MA–HP was not restricted to a composition of (Bi2Te3)0.25(Sb2Te3)0.75, which has the minimum phonon thermal conductivity in the case of melt growth.
Source: MATERIALS TRANSACTIONS
Authors: Masato Kitamura, Kazuhiro Hasezaki
Institution: Tokushima University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2552982091