Effects of Ag Addition on High Temperature Thermoelectric Properties of (Ca_0.9Gd_0.1)₃Co₄O₉ Ceramics

Abstract:

A series of (Ca0.9Gd0.1)3Co4O9/xAg(x=0, 0.1, 0.15, 0.2) ceramics were prepared by a polyacrylamide gel method and Spark Plasma Sintering. Scanning electron microscopy (SEM) revealed that small size Ag particles were dispersed into the (Ca0.9Gd0.1)3Co4O9(CGCO) matrix. The electrical conductivity of the composites was obviously higher than that of (Ca0.9Gd0.1)3Co4O9, and increased with increase of Ag content. However, the addition of Ag seemed to have a negative impact on the Seebeck coefficient (S) of the composites samples due to its poor S. Since the increase of electrical conductivity (σ) is more significant than the degradation of S, the power factor (P=σS2) was found to be improved by the addition of Ag. At 973 K, the P value of the sample with x =0.2 reached 3.17×10-4 W•m-1•K-2, which was 12.5% higher than that of Ca3Co4O9(CCO) bulk material.

• Periodical: Materials Science Forum (Volume 650)
• Pages: 132-136
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.650.132
• Online since: May 2010
• Authors: Yan Lu, Ying Song, Jin Feng, Fu Ping Wang
• Keywords: Ag Addition, Ca₃Co₄O₉, Gd-Doped, Thermoelectric Property

References

[1] I. Terasaki, Y. Sasago, and K. Uchinokura. Phys. Rev B. 56 (1997), 12685-12687.

[2] Y. F. Hu E. Sutter, W. D. Si, and Q. Li. Appl. Phys. Lett. 87 (2005), 1712-1719.

[3] P. Limelette, V. Hardy, P. S. Auban. Phys. Rev B. 71(23) (2005), 1098-0121.

[4] D. L. Wang, L. D. Chen, Q. Wang, et al. J Alloy Compd. 376 (2004), 58-61.

[5] C. J. Liu, L. C. Huang, J. S. Wang. Appl. Phys. Lett. 89 (2006), 1-3.

[6] G. J. Xu, R. Funahashi, et al. Appl. Phys. Lett. 20(80) (2002), 3760-3762.

[7] I. Matsubara, .R. Funahashi, T. Takeuchi, et al. Appl. Phys. Lett. 78(23) (2001), 3627-3629.

[8] M. Prevel, O. Perez, J.G. Noudem. Solid State Sci. (2007), 1-16.

[9] I. Matsubara, et al. International Confcrcnc on Thermoclectrics. 20 (2001), 172-175.

[10] E. Guilmeau, M. Pollet, et al. Mater Res. Bull. 43 (2008), 394-400.

[11] Y. F. Zhang, J.X. Zhang, Q.M. Lu. Ceram Int. 33 (2007), 1305-1308.

[12] M. Masashi, G. Emmanuel, et al. J Mater Res. 9(20) (2005), 2491-2497.

[13] P. H. Xiang, Y. Kinemuchi, H. Kaga. J Alloy Compd. 454 (2008), 364-369.

[14] Y. Song, Q. Sun, L.R. Zhao, F.P. Wang. Mater. Chem. Phys. 113 (2009), 645-649.

[15] I. Matsubara, R. Funahashi, T. Takeuchi, et al. J Appl Phys. 90 (2001), 462-465.

[16] I. Mikio, F. Daisuke. J Alloy and Compd. 450 (2008), 517-520.

[17] A. C. Masset, C. Michel, A. Maignan, et al. Phys Rev B. 62 (2000), 166-175.

[18] M. Mikami, N. Ando, et al. J Solid State Chem. 178 (2005), 2186-2190.