Influence of Tungsten Doping in La₂Mo₂O₉ Oxide-Ion Conductors by Dielectric Relaxation Measurements

Abstract:

The effects of tungsten doping in La₂Mo_2–yW_yO₉ (y =0, 0.25, 0.5, 1.0, 1.4) samples were studied using dielectric relaxation measurements. The results indicate that the solubility of W⁶⁺ in La₂Mo₂O₉ sample is about 25mol%, W⁶⁺ can suppress the α/β phase transition in the La₂Mo₂O₉. Additional to the low-temperature relaxation peak P_d associated with oxygen ion diffusion, a new dielectric loss peak P_h associated with a phase transition from the static disordered state to the dynamic disordered state of oxygen ion distribution was observed around 740 K. The conductivity of La₂Mo_1.9W_0.1O₉ sample is higher than that of the pure La₂Mo₂O₉, and then decrease with the increasing of the tungsten doping in La₂Mo_2–yW_yO₉ (y = 0.5, 1.0) samples in the whole measurement temperature.

• Periodical: Applied Mechanics and Materials (Volumes 130-134)
• Pages: 3302-3305
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.130-134.3302
• Online since: October 2011
• Authors: Dan Li, Xiang Hu Li
• Keywords: Conductivity, Dielectric Relaxation, La₂Mo₂O₉, Phase Transition

References

[1] P. Lacorre, F. Goutenoire, O. Bohnke and R. Retoux: Nature Vol. 404 (2000), p.856.

DOI: 10.1038/35009069

[2] F. Goutenoire, O. Isnard, R. Retoux and P. Lacorre . Chem. Mater., Vol. 12(2000), P. 2575.

[3] S. Georges, F. Goutenoire, Y. Laligant and P. Lacorre, J. Mater. Chem., Vol. 13(2003), p.2317.

[4] G. Corbel, Y. Laligant, F. Goutenoire, E. Suard, and P. Lacorre, Chem. Mater., Vol. 17, (2005), p.4678.

[5] J. H. Yang, Z. H. Gu, Z. Y. Wen, and D. S. Yan, Solid State Ion., Vol. 176, (2005), p.523.

[6] S. Georges, F. Goutenoire, P. Lacorre, and M. C. Steil, J. Eur. Ceram. Soc., Vol. 25, (2005), p.3619.

[7] D. Marrero-Lopez, J. Canales-Vazquez, J. C. Ruiz-Morales, J. T. S. Irvine, and R. Nunez, Electrochim. Acta 50, Vol. (2005), p.4385.

[8] D. Marrero-Lopez, J. Canales-Vazquez, W. Z. Zhou, J. T. S. Irvine, and P. Nunez, J. Solid State Chem., Vol. 179, (2006), p.278.

[9] D. Li , X.P. Wang, Z. Zhuang, J.X. Wang, C. Li , Q.F. Fang, Materials Research Bulletin, Vol. 44 (2009), p.446.

[10] X. P. Wang and Q. F. Fang, J. Phys. Condensed Matt., Vol. 13, (2001), p.1641.

[11] X. P. Wang, Q. F. Fang, Z. S. Li, G. G. Zhang, and Z. G. Yi, Appl. Phys. Lett., Vol. 81(2002), p.3434.

[12] X. P. Wang and Q. F. Fang, Phys. Rev. B, Vol. 65, (2002), p.064304.

[13] X. P. Wang, Z. J. Cheng, Q. F. Fang, Solid State Ionics, Vol. 176, (2005), p.761.

[14] X. P. Wang, D. Li, Q.F. Fang, Z.J. Cheng, G. Corbel, and P. Lacorre, Appl. Phys. Lett., Vol. 89, (2006), 021904.

[15] F. J. Liang, X. P. Wang, Q. F. Fang, J. X. Wang, C. Li, D. Li, and Z. Zhuang, Phys. Rev. B, Vol. 74, (2006), 014112.