Integrating Band Structure Engineering with All-Scale Hierarchical Structuring for High Thermoelectric Performance in PbTe System

Journal Article · Wed Oct 12 00:00:00 EDT 2016 · Advanced Energy Materials

DOI:https://doi.org/10.1002/aenm.201601450· OSTI ID:1397218

Pei, Yanling ^[1]; Tan, Gangjian ^[2]; Feng, Dan ^[3]; Zheng, Lei ^[1]; Tan, Qing ^[4]; Xie, Xiaobing ^[3]; Gong, Shengkai ^[1]; Chen, Yue ^[5]; Li, Jing-Feng ^[4]; He, Jiaqing ^[3]; Kanatzidis, Mercouri G. ^[2]; Zhao, Li-Dong ^[1]

---

1. Beihang Univ., Beijing (China)
2. Northwestern Univ., Evanston, IL (United States)
3. South Univ. of Science and Technology of China, Shenzhen (China); Shenzhen Key Lab. of Thermoelectric Materials, Shenzhen (China)
4. Tsinghua Univ., Beijing (China)
5. Univ. of Hong Kong (Hong Kong)

PbTe _{1− x} Se _x ‐2%Na‐y%SrTe system is investigated and a high maximum ZT of 2.3 at 923 K for PbTe _0.85 Se _0.15 ‐2%Na‐4%SrTe is reported. This is achieved by performing electronic band structures modifications as well as all‐scale hierarchical structuring and combining the two effects. It is found that high ZTs in PbTe _0.85 Se _0.15 ‐2%Na‐4%SrTe are possible at all temperature from 300 to 873 K with an average ZT _ave of 1.23. The high performance in PbTe _{1− x} Se _x ‐2%Na‐y%SrTe can be achieved by either choosing PbTe‐2Na‐4SrTe or PbTe _0.85 Se _0.15 ‐2Na as a matrix. At room temperature the carrier mobility shows negligible variations as SrTe fraction is increased, however the lattice thermal conductivity is significantly reduced from ≈1.1 to ≈0.82 W m ⁻¹ K ⁻¹ when 5.0% SrTe is added, correspondingly, the lattice thermal conductivity at 923 K decreases from ≈0.59 to ≈0.43 W m− ¹ K ⁻¹ . The power factor maxima of PbTe _{1− x} Se _x ‐2Na‐4SrTe shift systematically to higher temperature with rising Se fractions due to bands divergence. The maximum power factors reach ≈27, ≈30, ≈31 μW cm ⁻¹ K ⁻² for the x = 0, 0.05, and 0.15 samples peak at 473, 573, and 623 K, respectively. The results indicate that ZT can be increased by synergistic integration of band structure engineering and all‐scale hierarchical architectures.

• Research Organization: Energy Frontier Research Centers (EFRC) (United States). Revolutionary Materials for Solid State Energy Conversion (RMSSEC)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0001054
• OSTI ID: 1397218
• Alternate ID(s): OSTI ID: 1400584
• Journal Information: Advanced Energy Materials, Vol. 7, Issue 3; Related Information: RMSSEC partners with Michigan State University (lead); University of California, Los Angeles; University of Michigan; Northwestern University; Oak Ridge National Laboratory; Ohio State University; Wayne State University; ISSN 1614-6832
• Publisher: Wiley
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE