Structural, electrical, and thermoelectric properties of bismuth telluride: Silicon/carbon nanocomposites thin films

Journal Article · Thu Aug 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4894145· OSTI ID:22314334

Agarwal, Khushboo

In this study, the effect of the presence of secondary phases on the structural, electrical, and thermoelectric properties of nanocomposite Bi{sub 2}Te{sub 3} films prepared by co-sputtering of silicon and carbon with Bi{sub 2}Te{sub 3} has been investigated. Growth temperature and the presence of Si and C phase are observed to have a strong effect on the topography and orientation of crystallites. X-ray diffraction study demonstrates that Bi{sub 2}Te{sub 3} and Bi{sub 2}Te{sub 3}:C samples have preferred (0 0 15) orientation in comparison to Bi{sub 2}Te{sub 3}:Si sample, which have randomly oriented crystallites. Atomic force, conducting atomic force, and scanning thermal microscopy analysis show significant differences in topographical, electrical, and thermal conductivity contrasts in Bi{sub 2}Te{sub 3}:Si and Bi{sub 2}Te{sub 3}:C samples. Due to the randomly oriented crystallites and the presence of Si along the crystallite boundaries, appreciable Seebeck coefficient, higher electrical conductivity, and lower thermal conductivity is achieved resulting in relatively higher value of power factor (3.71 mW K{sup −2} m{sup −1}) for Bi{sub 2}Te{sub 3}:Si sample. This study shows that by incorporating a secondary phase along crystallite boundaries, microstructural, electrical, and thermoelectric properties of the composite samples can be modified.

• OSTI ID: 22314334
• Journal Information: Journal of Applied Physics, Vol. 116, Issue 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BISMUTH TELLURIDES
CARBON
COMPARATIVE EVALUATIONS
COMPOSITE MATERIALS
ELECTRIC CONDUCTIVITY
MICROSCOPY
MICROSTRUCTURE
NANOSTRUCTURES
POWER FACTOR
RANDOMNESS
SILICON
SPUTTERING
THERMAL CONDUCTIVITY
THERMOELECTRIC PROPERTIES
THIN FILMS
X-RAY DIFFRACTION