Thermal and electronic properties of Bi1-xsbx alloys

• Published in: Journal of alloys and compounds 2009-01, Vol.467 (1-2), p.305-309
• Main Authors: DUTTA, Soma, SHUBHA, V, RAMESH, T. G, D'SA, Florita
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; Electronic transport in condensed matter; Exact sciences and technology; Physics; Thermoelectric and thermomagnetic effects
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2007.11.146

Polycrystalline Bi1 - xSbx (x = 0.1,0.12 and 0.15) semiconducting alloys were synthesized by mechanical alloying in order to achieve homogeneous thermoelectric materials with improved mechanical strength. The homogeneity of the powder samples were repeatedly checked by X-ray diffraction and scanning electron microscopy to standardize the milling conditions. The best possible homogenized material was developed with the milling conditions of BPR 30:1, ball diameter 30 mm, 400 rpm and milling time of 15 h. The electrical resistivity, thermoelectric power and thermal conductivity were measured in the temperature range 300-500 K. It was found through these experiments that the composition with x = 0.12 behaved in a normal semiconducting way, whereas the other two compositions (x = 0.10 and 0.15) showed degenerate semiconductor behaviour. These features have been qualitatively explained from the band structure and interband scattering mechanisms.