High-performance bulk thermoelectrics with all-scale hierarchical architectures

  • A Corrigendum to this article was published on 24 October 2012


With about two-thirds of all used energy being lost as waste heat, there is a compelling need for high-performance thermoelectric materials that can directly and reversibly convert heat to electrical energy. However, the practical realization of thermoelectric materials is limited by their hitherto low figure of merit, ZT, which governs the Carnot efficiency according to the second law of thermodynamics. The recent successful strategy of nanostructuring to reduce thermal conductivity has achieved record-high ZT values in the range 1.5–1.8 at 750–900 kelvin1,2,3, but still falls short of the generally desired threshold value of 2. Nanostructures in bulk thermoelectrics allow effective phonon scattering of a significant portion of the phonon spectrum, but phonons with long mean free paths remain largely unaffected. Here we show that heat-carrying phonons with long mean free paths can be scattered by controlling and fine-tuning the mesoscale architecture of nanostructured thermoelectric materials. Thus, by considering sources of scattering on all relevant length scales in a hierarchical fashion—from atomic-scale lattice disorder and nanoscale endotaxial precipitates to mesoscale grain boundaries—we achieve the maximum reduction in lattice thermal conductivity and a large enhancement in the thermoelectric performance of PbTe. By taking such a panoscopic approach to the scattering of heat-carrying phonons across integrated length scales, we go beyond nanostructuring and demonstrate a ZT value of 2.2 at 915 kelvin in p-type PbTe endotaxially nanostructured with SrTe at a concentration of 4 mole per cent and mesostructured with powder processing and spark plasma sintering. This increase in ZT beyond the threshold of 2 highlights the role of, and need for, multiscale hierarchical architecture in controlling phonon scattering in bulk thermoelectrics, and offers a realistic prospect of the recovery of a significant portion of waste heat.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: All-length-scale hierarchy in thermoelectric materials.
Figure 2: Thermoelectric properties of SPS and ingot samples of PbTe–SrTe doped with 2 mol% Na.
Figure 3: Micro and nanostructures in SPS PbTe–SrTe(4 mol%) doped with 2 mol% Na.
Figure 4: Compositional analysis of SPS PbTe–SrTe(4 mol%) doped with 2 mol% Na.


  1. 1

    Snyder, J. G. & Toberer, E. S. Complex thermoelectric materials. Nature Mater. 7, 105–114 (2008)

  2. 2

    Chen, G., Dresselhaus, M. S., Dresselhaus, G., Fleurial, J. P. & Caillat, T. Recent development in thermoelectric materials. Int. Mater. Rev. 48, 45–66 (2003)

  3. 3

    Sootsman, J., Chung, D. Y. & Kanatzidis, M. G. New and old concepts in thermoelectric materials. Angew. Chem. Int. Ed. 48, 8616–8639 (2009)

  4. 4

    Rowe, D. M. CRC Handbook of Thermoelectrics: Macro to Nano (CRC/Taylor & Francis, 2006)

  5. 5

    Tritt, T. M. . (ed). Recent Trends in Thermoelectric Materials Research I (Semiconductors and Semimetals Vol. 69, Academic, 2000); Recent Trends in Thermoelectric Materials Research II (Semiconductors and Semimetals Vol. 70, Academic, 2000); Recent Trends in Thermoelectric Materials Research III (Semiconductors and Semimetals Vol. 71, Academic, 2001)

  6. 6

    Poudel, B. et al. High-thermoelectric performance of nanostructured bismuth antimony telluride bulk alloys. Science 320, 634–638 (2008)

  7. 7

    Venkatasubramanian, R., Siivola, E., Colpitts, V. & O’Quinn, B. Thin-film thermoelectric devices with high room-temperature figures of merit. Nature 413, 597–602 (2001)

  8. 8

    Hsu, K. F. et al. Cubic AgPbmSbTe2+m: bulk thermoelectric materials with high figure of merit. Science 303, 818–821 (2004)

  9. 9

    Poudeu, P. F. P. et al. High thermoelectric figure of merit and nanostructuring in bulk p-type Na1−xPbmSbyTe2+m . Angew. Chem. Int. Ed. 45, 3835–3839 (2006)

  10. 10

    Girard, S. N. et al. High performance Na-doped PbTe-PbS thermoelectric materials: electronic density of states modification and shape-controlled nanostructures. J. Am. Chem. Soc. 133, 16588–16597 (2011)

  11. 11

    Pei, Y. et al. Convergence of electronic bands for high-performance bulk thermoelectric. Nature 473, 66–69 (2011)

  12. 12

    Heremans, J. P. et al. Enhancement of thermoelectric efficiency in PbTe by distortion of the electronic density of states. Science 321, 554–557 (2008)

  13. 13

    Shi, X. et al. Multiple-filled skutterudites: high thermoelectric figure of merit through separately optimizing electrical and thermal transport. J. Am. Chem. Soc. 133, 7837–7846 (2011)

  14. 14

    Biswas, K. et al. Strained endotaxial nanostructures with high thermoelectric figure of merit. Nature Chem. 3, 160–166 (2011)

  15. 15

    Zhu, G. H. et al. Increased phonon scattering by nanograins and point defects in nanostructured silicon with a low concentration of germanium. Phys. Rev. Lett. 102, 196803 (2009)

  16. 16

    Martin, J., Wang, L., Chen, L. & Nolas, G. S. Enhanced Seebeck coefficient through energy-barrier scattering in PbTe nanocomposite. Phys. Rev. B 79, 115311 (2009)

  17. 17

    Ravich, Y. I., Efimova, B. A. & Smirnov, I. A. Semiconducting Lead Chalcogenides Vol. 5 184–192 (Plenum, 1970)

  18. 18

    Crocker, A. J. & Rogers, L. M. Valence band structure of PbTe. J. Phys. Colloq. 29 (C4). 129–132 (1968)

  19. 19

    Airapetyants, S. V. & Vinogradova, M. N. Durbrovskaya, I. N., Kolomoets, N. V. & Rudnik, I. M. Structure of the valance band of heavily doped lead telluride. Sov. Phys. Solid State 8, 1069–1072 (1966)

  20. 20

    Johnsen, S. et al. Nanostructures boost the thermoelectric performance of PbS. J. Am. Chem. Soc. 133, 3460–3470 (2011)

  21. 21

    May, A. F., Fleurial, J.-P. & Snyder, G. J. Thermoelectric performance of lanthanum telluride produced via mechanical alloying. Phys. Rev. B 78, 125205 (2008)

  22. 22

    Goldsmid, H. J. Thermoelectric Refrigeration (Plenum, 1964)

  23. 23

    Qiu, B., Bao, H., Zhang, G., Wu, Y. & Ruan, X. Molecular dynamics simulations of lattice thermal conductivity and spectral phonon mean free path of PbTe: bulk and nanostructures. Comput. Mater. Sci. 53, 278–285 (2012)

  24. 24

    Tian, Z. et al. Phonon conduction in PbSe, PbTe and PbTe1−xSex from first-principle calculations. Phys. Rev. B 85, 184303 (2012)

  25. 25

    Esfarjani, K., Chen, G. & Stokes, H. T. Heat transport in silicon from first-principle calculations. Phys. Rev. B 84, 085204 (2011)

  26. 26

    Hÿtch, M. J., Snoeck, E. & Kilaas, R. Quantitative measurement of displacement and strain fields from HREM micrographs. Ultramicroscopy 74, 131–146 (1998)

  27. 27

    Seidman, D. N. Three-dimensional atom-probe tomography: advances and applications. Annu. Rev. Mater. Res. 37, 127–158 (2007)

  28. 28

    Crocker, A. J. & Dorning, B. F. Diffusion of sodium in lead telluride. J. Phys. Chem. Solids 29, 155–161 (1968)

  29. 29

    Blachnik, R. & Igel, R. Thermodynamic properties of IV–VI compound: lead chalcogenides. Z. Naturforsch. B 29, 625–629 (1974)

Download references


This work was supported by the Energy Frontier Research Center for Revolutionary Materials for Solid State Energy Conversion, funded by the US Department of Energy, Office of Science, Basic Energy Sciences under award number DE-SC0001054. TEM was performed in the (EPIC) (NIFTI) (Keck-II) facility of the NUANCE Center at Northwestern University. The spark plasma sintering system at Michigan State University is supported by ONR DURIP. APT was performed at NUCAPT and supported by NSF-MRI (DMR-0420532), ONR-DURIP (N00014-0400798, N00014-0610539, N00014-0910781), MRSEC (DMR-1121262) and ISEN at Northwestern University.

Author information

K.B. synthesized the samples and designed and carried out thermoelectric experiments. J.H. performed the TEM experiments. I.D.B. performed the APT measurements. C.-I.W. and T.P.H. performed the spark plasma sintering. K.B., J.H., I.D.B., D.N.S., V.P.D. and M.G.K. conceived the experiments, analysed the results and wrote and edited the manuscript.

Correspondence to Mercouri G. Kanatzidis.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

This file contains Supplementary Text and Data, Supplementary Figures 1-8, Supplementary Tables 1-3 and Supplementary References. (PDF 656 kb)

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Biswas, K., He, J., Blum, I. et al. High-performance bulk thermoelectrics with all-scale hierarchical architectures. Nature 489, 414–418 (2012). https://doi.org/10.1038/nature11439

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.