Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Superparamagnetic enhancement of thermoelectric performance

A Corrigendum to this article was published on 08 November 2017

Abstract

The ability to control chemical and physical structuring at the nanometre scale is important for developing high-performance thermoelectric materials1. Progress in this area has been achieved mainly by enhancing phonon scattering and consequently decreasing the thermal conductivity of the lattice through the design of either interface structures at nanometre or mesoscopic length scales2,3,4,5,6 or multiscale hierarchical architectures7,8. A nanostructuring approach that enables electron transport as well as phonon transport to be manipulated could potentially lead to further enhancements in thermoelectric performance. Here we show that by embedding nanoparticles of a soft magnetic material in a thermoelectric matrix we achieve dual control of phonon- and electron-transport properties. The properties of the nanoparticles—in particular, their superparamagnetic behaviour (in which the nanoparticles can be magnetized similarly to a paramagnet under an external magnetic field)—lead to three kinds of thermoelectromagnetic effect: charge transfer from the magnetic inclusions to the matrix; multiple scattering of electrons by superparamagnetic fluctuations; and enhanced phonon scattering as a result of both the magnetic fluctuations and the nanostructures themselves. We show that together these effects can effectively manipulate electron and phonon transport at nanometre and mesoscopic length scales and thereby improve the thermoelectric performance of the resulting nanocomposites.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Microstructures of the as-prepared powders and bulk materials of xCo/Ba0.3In0.3Co4Sb12 with x = 0.2%.
Figure 2: Measured magnetic properties.
Figure 3: Electrical and thermal properties in the temperature range 300–850 K.
Figure 4: Thermoelectromagnetic effects induced by Co nanoparticles with diameters of 5–10 nm.

Similar content being viewed by others

References

  1. Dresselhaus, M. S. et al. New directions for low-dimensional thermoelectric materials. Adv. Mater. 19, 1043–1053 (2007)

    Article  CAS  Google Scholar 

  2. Zhou, M., Li, J. F. & Kita, T. Nanostructured AgPbmSbTem+2 system bulk materials with enhanced thermoelectric performance. J. Am. Chem. Soc. 130, 4527–4532 (2008)

    Article  CAS  Google Scholar 

  3. Hu, Y. J., Zeng, L. P., Minnich, A. J., Dresselhaus, M. S. & Chen, G. Spectral mapping of thermal conductivity through nanoscale ballistic transport. Nat. Nanotechnol. 10, 701–706 (2015)

    Article  ADS  CAS  Google Scholar 

  4. Zhao, W. Y. et al. Enhanced thermoelectric performance via randomly arranged nanopores: excellent transport properties of YbZn2Sb2 nanoporous materials. Acta Mater. 60, 1741–1746 (2012)

    Article  CAS  Google Scholar 

  5. Fu, C. G. et al. Realizing high figure of merit in heavy-band p-type half-Heusler thermoelectric materials. Nat. Commun. 6, 8144 (2015)

    Article  ADS  Google Scholar 

  6. Luo, Y. B. et al. Progressive regulation of electrical and thermal transport properties to high-performance CuInTe2 thermoelectric materials. Adv. Energy Mater. 6, 1600007 (2016)

    Article  Google Scholar 

  7. Biswas, K. et al. High-performance bulk thermoelectrics with all-scale hierarchical architectures. Nature 489, 414–418 (2012)

    Article  ADS  CAS  Google Scholar 

  8. Wu, H. J. et al. Broad temperature plateau for thermoelectric figure of merit ZT > 2 in phase-separated PbTe0.7S0.3 . Nat. Commun. 5, 4515 (2014)

    Article  ADS  CAS  Google Scholar 

  9. Bell, L. E. Cooling, heating, generating power, and recovering waste heat with thermoelectric systems. Science 321, 1457–1461 (2008)

    Article  ADS  CAS  Google Scholar 

  10. Sales, B. C., Mandrus, D. & Williams, R. K. Filled skutterudite antimonides: a new class of thermoelectric materials. Science 272, 1325–1328 (1996)

    Article  ADS  CAS  Google Scholar 

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

    Article  ADS  CAS  Google Scholar 

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

    Article  ADS  CAS  Google Scholar 

  13. Liu, H. L. et al. Copper ion liquid-like thermoelectrics. Nat. Mater. 11, 422–425 (2012)

    Article  ADS  Google Scholar 

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

    Article  ADS  CAS  Google Scholar 

  15. Zhao, L. D. et al. Ultrahigh power factor and thermoelectric performance in hole-doped single-crystal SnSe. Science 351, 141–144 (2016)

    Article  ADS  CAS  Google Scholar 

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

    Article  ADS  CAS  Google Scholar 

  17. Liu, W. et al. Convergence of conduction bands as a means of enhancing thermoelectric performance of n-type Mg2Si1−xSnx solid. Phys. Rev. Lett. 108, 166601 (2012)

    Article  ADS  Google Scholar 

  18. Zhao, W. Y. et al. Enhanced thermoelectric performance in barium and indium double-filled skutterudite bulk materials via orbital hybridization induced by indium filler. J. Am. Chem. Soc. 131, 3713–3720 (2009)

    Article  CAS  Google Scholar 

  19. Zhao, W. Y. et al. Multi-localization transport behaviour in bulk thermoelectric materials. Nat. Commun. 6, 6197 (2015)

    Article  ADS  CAS  Google Scholar 

  20. Zhao, W. Y. et al. Magnetoelectric interaction and transport behaviors in magnetic nanocomposite thermoelectric materials. Nat. Nanotechnol. 12, 55–60 (2016)

    Article  ADS  Google Scholar 

  21. Pappas, P. T. The original ampere force and Biot–Savart and Lorentz forces. Il Nuovo Cimento B 76, 189–197 (1983)

    Article  ADS  Google Scholar 

  22. Chen, L. D. et al. Anomalous barium filling fraction and n-type thermoelectric performance of BayCo4Sb12 . J. Appl. Phys. 90, 1864–1868 (2001)

    Article  ADS  CAS  Google Scholar 

  23. Micha, J. S., Dieny, B., Régnard, J. R., Jacquot, J. F. & Sort, J. Estimation of the Co nanoparticles size by magnetic measurements in Co/SiO2 discontinuous multilayers. J. Magn. Magn. Mater. 272–276 (Suppl.), E967–E968 (2004)

    Article  Google Scholar 

  24. Cutler, M., Leavy, J. F. & Fitzpatrick, R. L. Electronic transport in semimetallic cerium sulfide. Phys. Rev. 133, A1143–A1152 (1964)

    Article  ADS  Google Scholar 

  25. Rowe, D. M. & Bhandari, C. M. Modern Thermoelectric 26 (Reston Publishing Company, 1983)

  26. Boona, S. R., Vandaele, K., Boona, I. N., Mccomb, D. W. & Heremans, J. P. Observation of spin Seebeck contribution to the transverse thermopower in Ni–Pt and MnBi–Au bulk nanocomposites. Nat. Commun. 7, 13714 (2016)

    Article  ADS  CAS  Google Scholar 

  27. Rhoderick, E. H. & Williams, R. H. Metal–Semiconductor Contacts 2nd edn, 10–15 (Clarendon Press, 1988)

  28. Wood, D. M. Classical size dependence of the work function of small metallic spheres. Phys. Rev. Lett. 46, 749 (1981)

    Article  ADS  CAS  Google Scholar 

  29. Dhara, S ., Chowdhury, R. R. & Bandyopadhyay, B. Observation of resistivity minimum at low temperature in CoxCu1−x (x ~ 0.17–0.76) nanostructured granular alloys. Phys. Rev. B 93, 214413 (2016)

    Article  ADS  Google Scholar 

  30. Zhao, W. Y. et al. Synthesis and high temperature transport properties of barium and indium double-filled skutterudites BaxInyCo4Sb12–z . J. Appl. Phys. 102, 113708 (2007)

    Article  ADS  Google Scholar 

  31. Fitsul, V. I. Heavily Doped Semiconductors 139–169 (Plenum Press, 1969)

  32. Snyder, G. J., Christensen, M., Nishibori, E. J., Caillat, T. & Iversen, B. B. Disordered zinc in Zn4Sb3 with phonon glass, electron crystal thermoelectric properties. Nat. Mater. 3, 458–463 (2004)

    Article  ADS  CAS  Google Scholar 

  33. Kim, S. I. et al. Dense dislocation arrays embedded in grain boundaries for high-performance bulk thermoelectrics. Science 348, 109–114 (2015)

    Article  ADS  CAS  Google Scholar 

  34. Nolas, G. S., Kendziora, C. A. & Takizawa, H. Polarized Raman-scattering study of Ge and Sn-filled CoSb3 . J. Appl. Phys. 94, 7440–7444 (2003)

    Article  ADS  CAS  Google Scholar 

  35. Sucksmith, W. & Thompson, J. E. The magnetic anisotropy of cobalt. Proc. R. Soc. Lond. A 225, 362–375 (1954)

    Article  ADS  CAS  Google Scholar 

  36. Bozorth, R. M. Directional ferromagnetic properties of metals. J. Appl. Phys. 8, 575–588 (1937)

    Article  ADS  Google Scholar 

  37. Tatsumoto, E., Okamoto, T., Iwata, N. & Kadena, Y. Temperature dependence of the magnetocrystalline anisotropy constants K1 and K2 of nickel. J. Phys. Soc. Jpn. 20, 1541–1542 (1965)

    Article  ADS  CAS  Google Scholar 

  38. Yang, C. C. & Jiang, Q. Size and interface effects on critical temperatures of ferromagnetic, ferroelectric and superconductive nanocrystals. Acta Mater. 53, 3305–3311 (2005)

    Article  CAS  Google Scholar 

  39. Mohn, P. & Wohlfarth, E. P. The Curie temperature of the ferromagnetic transition metals and their compounds. J. Phys. F 17, 2421–2430 (1987)

    Article  ADS  CAS  Google Scholar 

  40. Edgar, E. L. Periodic Table of the Elements 1 (Gaston, 1993)

  41. King, H. W. in Physical Metallurgy 3rd edn (eds Cahn, R. W . & Haasen, P. ) 59–63 (Amsterdam, 1983)

  42. Jiang, Q. & Lang, X. Y. Glass transition of low-dimensional polystyrene. Macromol. Rapid Commun. 25, 825–828 (2004)

    Article  CAS  Google Scholar 

  43. Gao, Y. L. Surface analytical studies of interfaces in organic semiconductor devices. Mater. Sci. Eng. Rep. 68, 39–87 (2010)

    Article  Google Scholar 

  44. Ertl, G. & Küppers, J. Low Energy Electrons and Surface Chemistry 87–143 (VCH, 1985)

  45. Michaelson, H. B. The work function of the elements and its periodicity. J. Appl. Phys. 48, 4729–4733 (1977)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Natural Science Foundation of China (numbers 51620105014, 11274248, 51572210 and 51521001) and the National Basic Research Program of China (973-program) (number 2013CB632505). XRD, FESEM, EPMA, HRTEM and Raman-scattering experiments were performed at the Center for Materials Research and Testing at Wuhan University of Technology. Hall measurements were performed at the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing at Wuhan University of Technology. XPS were recorded at the Key Laboratory of Catalysis and Materials Science at the State Ethnic Affair Commission and Ministry of Education of South-Central University for Nationalities. The measurements of static magnetic properties and UPS were performed at the School of Physics and Technology at Wuhan University. We thank S. B. Mu, W. Y. Chen, M. J. Yang, C. H. Shen, X. Q. Liu and Y. Y. Qi for help with structure characterization, J. R. Sun and T. Y. Zhao from the Institute of Physics of CAS for suggestions, and W. Wang from Dongguan University of Technology for preparing magnetic nanoparticles.

Author information

Authors and Affiliations

Authors

Contributions

W. Zhao and Q.Z. designed a magnetic nanocomposite thermoelectric material for this work. Z.L., C.L., S.M., D.H. and P.J. synthesized the samples. W. Zhao, Z.L., Z.S., X.M., H.Z., X.S., J.S. and X.T. carried out the thermoelectric-property and Hall measurements. W. Zhu, X.N., P.W. and Y.L. performed the electron microscopy analysis and XPS experiments. W. Zhao, P.W., Z.S., Y.L., C.L., J.S., B.S. and X.D. performed the magnetic measurements. W. Zhao, Q.Z., Z.L., Z.S., J.Y. and B.S. conceived the experiments, analysed the results and wrote and edited the manuscript. All authors read the paper and commented on the text.

Corresponding authors

Correspondence to Qingjie Zhang or Jihui Yang.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Additional information

Reviewer Information Nature thanks B. Sales and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Figure 1 Effect of Co nanoparticles on structure.

a, XRD patterns of Co nanoparticles. b, XRD patterns of the first batch of xCo/Ba0.3In0.3Co4Sb12 (x = 0, 0.1%, 0.2% and 0.3%; labelled MNC00, MNC01, MNC02 and MNC03). c, Raman spectra of the first batch of samples. dg, BEIs of the first batch of samples.

Extended Data Figure 2 Effect of the Co nanoparticles on microstructure.

a, b, FESEM images of MNC00 (a) and MNC02 (b). c, HRTEM image of MNC02. dg, FESEM images of MNC00R, MNC01R, MNC02R and MNC03R, respectively.

Extended Data Figure 3 Theoretical blocking temperature (TB) and Curie temperature (TC), and the Ohmic contact experiment.

a, c, e, Theoretical TB dependence of the critical diameter DC. b, d, f, Theoretical TC dependence of the critical diameter DC. The oval shaded areas delineated by dotted lines indicate the range of TB and TC for the Co and Ni nanoparticles diameters of 5–10 nm and the Fe nanoparticles diameters of 2–5 nm. g, Experimental sample for measuring the Ohmic contact between Co and filled skutterudite. Co was first evaporated onto the matrix and then Cu electrodes were connected with the Co using a tin solder. h, IV plot: a straight line through the origin (0, 0), demonstrating a good and stable Ohmic contact between the Co and the matrix, consistent with the analytical result from the work functions of the Co nanoparticles and the matrix.

Extended Data Figure 4 Experimental data from Hall measurements and theoretical Lorenz number (L).

a, b, The first batch of samples. c, d, The second batch of samples. The measuring current remains unchanged at 100 mA. The magnetic field is varied in the range 0.1–1.2 T. The ΔVxy values measured in the range 0.5–1.2 T are used to linearly fit the Hall coefficient. e, f, Temperature dependence of L for the first (e; MNC00, MNC01, MNC02 and MNC03) and second (f; MNC00R, MNC01R, MNC02R, MNC03R and MNC04R) batches of MNC thermoelectric materials batch in the range 300–850 K.

Extended Data Figure 5 Effect of the Co nanoparticles on the electrical and thermal transport properties in the range 300–850 K.

af, The first batch of samples. gl, The second batch samples. al, Temperature dependence of the electric conductivity σ (a, g), the Seebeck coefficient α (b, h), the power factor α2σ (c, i), the thermal conductivity κ (d, j), lattice thermal conductivity κL (e, k) and ZT (f, l). The insets in d and j show the temperature dependence of the carrier thermal conductivity κE. The error bars in f and l are set to 5%.

Extended Data Figure 6 Effect of the Fe, Co and Ni nanoparticles on the thermoelectric and magnetic properties.

ad, Temperature dependence of the electric conductivity σ (a) Seebeck coefficient α (b), thermal conductivity κ (d) and ZT for MNC00R and xTM/Ba0.3In0.3Co4Sb12 (TM = Fe, Co or Ni) with x = 0.2%, labelled MNC02R_Fe, MNC02R_Co and MNC02R_Ni, respectively. The inset in c shows the temperature dependence of the lattice thermal conductivity κL. eh, MH curves at room temperature. The insets in eh show close-ups near zero field.

Extended Data Figure 7 Experimental evidence of the superparamagnetism of the Co nanoparticles with diameters of 5–10 nm.

a, ZFC and FC MT curves. b, MH curves at 300 K and 450 K. c, Langevin fitting of the MH curves at 450 K. d, TEM image of the Co nanoparticles. The inset in b shows the MH curves near zero field. The inset in c shows the results of the Langevin fitting.

Extended Data Figure 8 Experimental evidence of the superparamagnetism of the Fe nanoparticles with diameters of 2–5 nm.

a, ZFC and FC MT curves. b, MH curves at 50 K and 350 K. c, Langevin fitting of the MH curves at 350 K. d, TEM image of the Fe nanoparticles. The inset in b shows the MH curves near zero field. The inset in c shows the results of the Langevin fitting.

Extended Data Figure 9 Experimental evidence of the superparamagnetism of the Ni nanoparticles.

a, ZFC and FC MT curves. b, MH curves at 50 K and 350 K. c, Langevin fitting of the MH curves at 350 K. d, TEM image of the Ni nanoparticles with diameters of 5–10 nm. The inset in b shows the MH curves near zero field. The inset in c shows the results of the Langevin fitting.

Extended Data Table 1 Room-temperature charge-transport properties and scattering parameters for the first (MNC00, MNC01, MNC02 and MNC03) and second (MNC00R, MNC01R, MNC02R, MNC03R and MNC04R) batches of xCo/Ba0.3In0.3Co4Sb12 samples

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zhao, W., Liu, Z., Sun, Z. et al. Superparamagnetic enhancement of thermoelectric performance. Nature 549, 247–251 (2017). https://doi.org/10.1038/nature23667

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature23667

This article is cited by

Comments

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.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing