Year: 2007
Type: article
Abstract: Rod-like single crystals of Sr 6 Co 5 O 14.3 were grown by the flux method, and the electrical conductivity (σ), Seebeck coefficient ( S ) and power factor (σ S 2 ) were investigated in the temperature range of 300–900 K in air to explore the potential as thermoelectric materials. Sr 6 Co 5 O 14.3 is an oxygen-nonstoichiometric phase of Sr 6 Co 5 O 15 , which is a member of the homologous ( A 3 Co 2 O 6 ) m ( A 3 Co 3 O 9 ) n [ A =Ca, Sr, Ba] series including Ca 3 Co 2 O 6 ( m =1, n =0) and BaCoO 3 ( m =0, n =1) as the end members. The rod-like single crystals mainly grew along Co–O one-dimensional chains ( c -axis) consisting of face-sharing CoO 6 octahedra and CoO 6 triangular prisms. The electrical conductivity along the Co–O chains showed semiconducting behavior (260–9600 S m -1 in the temperature range of 300–900 K). The Seebeck coefficient was positive, and decreased with increasing temperature (280–140 µV K -1 ). The power factor increased with increasing temperature (0.20 × 10 -4 –1.9 × 10 -4 W m -1 K -2 ), which was about one order of magnitude larger than that of polycrystalline Sr 6 Co 5 O 15 .
DOI: 10.1143/jjap.46.256
Institution: Nagoya University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W1485567499