Details

Autor(en) / Beteiligte

• Sun, G. L.
• Li, L. L.
• Qin, X. Y.
• Li, D.
• Zou, T. H.
• Xin, H. X.
• Ren, B. J.
• Zhang, J.
• Li, Y. Y.
• Li, X. J.

Titel

Enhanced thermoelectric performance of nanostructured topological insulator Bi2Se3

Ist Teil von

• Applied physics letters, 2015-02, Vol.106 (5)

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2015

Quelle

American Institute of Physics

Beschreibungen/Notizen

• 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 cm2 V−1 s−1 to ∼600 cm2 V−1 s−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 Bi2Se3 at T = ∼570 K.