title: Promoting SnTe as an Eco-Friendly Solution for p-PbTe Thermoelectric via Band Convergence and Interstitial Defects.
abstract: Compared to commercially available p-type PbTe thermoelectrics, SnTe has a much bigger band offset between its two valence bands and a much higher lattice thermal conductivity, both of which limit its peak thermoelectric figure of merit, zT of only 0.4. Converging its valence bands or introducing resonant states is found to enhance the electronic properties, while nanostructuring or more recently introducing interstitial defects is found to reduce the lattice thermal conductivity. Even with an integration of some of the strategies above, existing efforts do not enable a peak zT exceeding 1.4 and usually involve Cd or Hg. In this work, a combination of band convergence and interstitial defects, each of which enables a ≈150% increase in the peak zT, successfully accumulates the zT enhancements to be ≈300% (zT up to 1.6) without involving any toxic elements. This opens new possibilities for further improvements and promotes SnTe as an environment-friendly solution for conventional p-PbTe thermoelectrics.
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Li
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Linglang
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing, 100190, China.
authors.forename: Binghui
authors.initials: B
authors.lastname: Ge
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Siqi
authors.initials: S
authors.lastname: Lin
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Xinyue
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing, 100190, China.
authors.forename: Yunjie
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800, Caoan Road, Shanghai, 201804, China.
authors.forename: Yanzhong
authors.initials: Y
authors.lastname: Pei
keywords: band convergence; eco-friendly; interstitial defects; thermoelectrics