Hostname: page-component-848d4c4894-p2v8j Total loading time: 0 Render date: 2024-05-06T01:48:57.329Z Has data issue: false hasContentIssue false
  • English
  • Français

Relationship between microstructure and thermoelectric properties of Bi2Sr2Co2Ox bulk materials

Published online by Cambridge University Press:  15 July 2014

Emmanuel Combe ,
Ryoji Funahashi ,
Feridoon Azough  and
Robert Freer
Emmanuel Combe
Affiliation:
Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology, Ikeda, Osaka 563-8577, Japan
Ryoji Funahashi*
Affiliation:
Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology, Ikeda, Osaka 563-8577, Japan; and CREST, Japan Science and Technology Agency, Chiyoda, Tokyo 102-0075, Japan
Feridoon Azough
Affiliation:
Materials Science Center, School of Materials, University of Manchester, Manchester M13 9PL, United Kingdom
Robert Freer
Affiliation:
Materials Science Center, School of Materials, University of Manchester, Manchester M13 9PL, United Kingdom
*
a)Address all correspondence to this author. e-mail: funahashi-r@aist.go.jp
Get access

Abstract

The thermoelectric properties of Bi2Sr2Co2Ox (BSC-222) bulk materials prepared by three different processing methods, i.e., conventional sintering, hot pressing, or partial melting, were investigated and compared. The electrical current, temperature difference for Seebeck coefficient, and thermal diffusion were measured in the same direction. The hot pressing and partial melting are effective processing methods for improving the electrical transport property in BSC-222 bulk materials due to an improvement of density in hot-pressed samples or by grain growth during partial melting process. For partially melted samples, a decrease in the thermal conductivity is also observed. The highest dimensionless thermoelectric figure of merit (ZT) values have been obtained in the sample prepared by partial melting method, for which ZT has been increased by a factor of 2.7 by comparison with bulk materials prepared by conventional sintering. At 700 °C in air, ZT value reaches 0.27 for partially melted Bi2Sr2Co2Ox bulk materials. This study shows that optimized electrical and thermal transport properties can be achieved in BSC-222 bulk materials possessing microstructures with both large average grain size and appropriate bulk density.

Type
Articles
Information
Journal of Materials Research , Volume 29 , Issue 12 , 28 June 2014 , pp. 1376 - 1382
Copyright
Copyright © Materials Research Society 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Poudel, B., Hao, Q., Ma, Y., Lan, Y., Minnich, A., Yu, B., Yan, X., Wang, D., Muto, A., Vashaee, D., Chen, X., Liu, J., Dresselhaus, M.S., Chen, G., and Ren, Z.: High-thermoelectric performance of nanostructured bismuth antimony telluride bulk alloys. Science 320, 634 (2008).Google Scholar
Terasaki, I., Sasago, Y., and Uchinokura, K.: Large thermoelectric power in NaCo2O4 single crystals. Phys. Rev. B 56(20), 12685 (1997).Google Scholar
Funahashi, R., Matsubara, I., Ikuta, H., Takeuchi, T., Mizutani, U., and Sodeoka, S.: An oxide single crystal with high thermoelectric performance in air. Jpn. J. Appl. Phys. 39, L1127 (2000).Google Scholar
Maignan, A., Hébert, S., Hervieu, M., Michel, C., Pelloquin, D., and Khomskii, D.: Magnetoresistance and magnetothermopower properties of Bi/Ca/Co/O and Bi(Pb)/Ca/Co/O misfit layer cobaltites. J. Phys.: Condens. Matter 15, 2711 (2003).Google Scholar
Funahashi, R. and Shikano, M.: Bi2Sr2Co2Oy whiskers for high thermoelectric figure of merit. Appl. Phys. Lett. 81(8), 1459 (2002).Google Scholar
Leligny, H., Grebille, D., Perez, O., Masset, A.C., Hervieu, M., and Raveau, B.: A five-dimensional structural investigation of the misfit layer compound [Bi0.87SrO2]2[CoO2]1.82. Acta Crystallogr., Sect. B 56, 173 (2000).Google Scholar
Funahashi, R., Matsubara, I., and Sodeoka, S.: Thermoelectric properties of Bi2Sr2Co2Ox polycrystalline materials. Appl. Phys. Lett. 76(17), 2385 (2000).Google Scholar
Shin, W. and Murayama, N.: Thermoelectric properties of (Bi,Pb)-Sr-Co-O oxide. J. Mater. Res. 15(2), 382 (2000).Google Scholar
Masuda, Y., Nagahama, D., Itahara, H., Tani, T., Seo, W.S., and Koumoto, K.: Thermoelectric performance of Bi- and Na-substituted Ca3Co4O9 improved through ceramic texturing. J. Mater. Chem. 13(5), 1094 (2003).Google Scholar
Shinzato, K. and Baba, T.: A laser flash apparatus for thermal diffusivity and specific heat capacity measurements. J. Therm. Anal. Calorim. 64, 413 (2001).Google Scholar
Rubešová, K., Hlásek, T., Jakeš, V., Sedmidubský, D., and Hejtmánek, J.: Water based sol-gel methods used for Bi-222 thermoelectrics preparation. J. Sol-Gel Sci. Technol. 64(1), 93 (2012).Google Scholar
Hsu, H.C., Lee, W.L., Wu, K.K., Kuo, Y.K., Chen, B.H., and Chou, F.C.: Enhanced thermoelectric figure-of-merit ZT for hole-doped Bi2Sr2Co2Oy through Pb substitution. J. Appl. Phys. 111, 103709 (2012).Google Scholar
Wang, S., Bai, Z., Wang, H., Lü, Q., Wang, J., and Fu, G.: High temperature thermoelectric properties of Bi2Sr2Co2Oy/Ag composites. J. Alloys Compd. 554, 254 (2013).Google Scholar
Muta, H., Kanemitsu, T., Kurosaki, K., and Yamanaka, S.: High-temperature thermoelectric properties of Nb-doped MNiSn (M=Ti, Zr) half-Heusler compound. J. Alloys Compd. 469, 50 (2009).Google Scholar