Details

Autor(en) / Beteiligte

• Liu, Wei-Shu
• Zhang, Qinyong
• Lan, Yucheng
• Chen, Shuo
• Yan, Xiao
• Zhang, Qian
• Wang, Hui
• Wang, Dezhi
• Chen, Gang
• Ren, Zhifeng

Titel

Thermoelectric Property Studies on Cu-Doped n-type CuxBi2Te2.7Se0.3 Nanocomposites

Ist Teil von

• Advanced energy materials, 2011-07, Vol.1 (4), p.577-587

Ort / Verlag

Weinheim: WILEY-VCH Verlag

Erscheinungsjahr

2011

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Combining high energy ball‐milling and hot‐pressing, significant enhancements of the thermoelectric figure‐of‐merit (ZT) have been reported for p‐type Bi0.4Sb1.6Te3 nanocomposites. However, applying the same technique to n‐type Bi2Te2.7Se0.3 showed no improvement on ZT values, due to the anisotropic nature of the thermoelectric properties of n‐type Bi2Te2.7Se0.3. Even though texturing was effective in improving peak ZT of Bi2Te2.7Se0.3 from 0.85 to 1.04, reproducibility from batch to batch remains unsatisfactory. Here, we show that good reproducibility can be achieved by introducing an optimal concentration of 0.01 copper (Cu) per Bi2Te2.7Se0.3 to make Cu0.01Bi2Te2.7Se0.3 samples. A peak ZT value of 0.99 was achieved in Cu0.01Bi2Te2.7Se0.3 samples without texturing. With texturing by re‐pressing, the peak ZT was increased to 1.06. Aging in air for over 5 months did not deteriorate but further improved the peak ZT to 1.10. The mechanism by which copper improves the reproducibility, enhances the carrier mobility, and reduces the lattice thermal conductivity is also discussed. Combining high energy ball milling and hot pressing, a significant enhancement on thermoelectric figure‐of‐merit (ZT) has been reported in p‐type Bi0.4Sb1.6Te3 nanocomposites, however the reproducibility from batch to batch is unsatisfactory. Improved reproducibility can be achieved by introducing a concentration of 0.01 Cu per Bi2Te2.7Se0.3 to give Cu0.01Bi2Te2.7Se0.3 samples. A peak ZT value of 0.99 is obtained in Cu0.01Bi2Te2.7Se0.3 samples without texturing. When textured by re‐pressing, the peak ZT can be increased to 1.06. Aging in air for over 5 months does not cause deterioration but further improved the peak ZT to 1.10.