Enhanced thermoelectric performance of nanostructured topological insulator Bi{sub 2}Se{sub 3}

Journal Article · Mon Feb 02 00:00:00 EST 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4907252· OSTI ID:22420261

Sun, G. L. ^[1]; Li, L. L.; Li, D.; Zou, T. H.; Xin, H. X.; Ren, B. J.; Zhang, J.; Li, Y. Y.; Li, X. J. ^[1]

---

1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031 Hefei (China)

To enhance thermoelectric performance by utilizing topological properties of topological insulators has attracted increasing attention. Here, we show that as grain size decreases from microns to ∼80 nm in thickness, the electron mobility μ increases steeply from 12–15 cm{sup 2} V{sup −1} s{sup −1} to ∼600 cm{sup 2} V{sup −1} s{sup −1}, owing to the contribution of increased topologically protected conducting surfaces. Simultaneously, its lattice thermal conductivity is lowered by ∼30%–50% due to enhanced phonon scattering from the increased grain boundaries. As a result, thermoelectric figure of merit, ZT, of all the fine-grained samples is improved. Specifically, a maximum value of ZT = ∼0.63 is achieved for Bi{sub 2}Se{sub 3} at T = ∼570 K.

• OSTI ID: 22420261
• Journal Information: Applied Physics Letters, Vol. 106, Issue 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BISMUTH SELENIDES
ELECTRICAL INSULATORS
ELECTRON MOBILITY
GRAIN BOUNDARIES
GRAIN SIZE
NANOSTRUCTURES
PERFORMANCE
PHONONS
TEMPERATURE RANGE 0400-1000 K
THERMAL CONDUCTIVITY