Room temperature thermal properties of Pb(Fe1/2Nb1/2)O3 ferroelectromagnetic ceramics
R. Fonta,b, E. Marínc, A. Lara–Bernalc, O. Raymondª, A. Calderónc, J. Portellesa,b, and J.M. Siqueirosª
ª Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 Carretera Tijuana–Ensenada, Ensenada, 22860, Baja California, México.
b Facultad de Física, Universidad de La Habana, San Lázaro y L, Vedado, La Habana, 10400, Cuba.
c Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada–Instituto Politécnico Nacional, Legaria 694, Col. Irrigación, 11500, México, D.F., México.
]]>Recibido el 14 de febrero de 2011
Aceptado el 11 de abril de 2011
Abstract
The thermal properties of ferroelectromagnetic Pb(Fe1/2Nb1/2)O3 ceramics obtained using the conventional ceramic method at different sintering temperatures between 850°C and 1000°C by stoichiometric mixing of the corresponding oxides and using different kinds of precursors, have been investigated for the first time. In particular the thermal conductivity was calculated from the measured values of thermal diffusivity and specific (volume) heat capacity using the photoacoustic technique and the temperature relaxation method, respectively. Whereas no influence of the kind of precursor used for sample preparation on the thermal conductivity (k) was observed, we have found that the value of k depends on sintering temperature and has a maximum for samples synthesized at 900°C, regardless of the use of precursors or not. This paper shows that such feature is determined by the competition of the thermal conductivity mechanisms inside the grains and those at the grain boundaries in combination with the morphologic features.
Keywords: Thermal diffusivity; thermal conductivity; specific heat capacity; ferroelectromagnetic; multiferroic; lead iron niobate (PFN).
Resumen
Se determinan por primera vez las propiedades térmicas de la cerámica ferroelectromagnética Pb(Fe1/2Nb1/2)O3 obtenida utilizando el método cerámico convencional a diferentes temperaturas de sinterización, entre 850° C y 1000° C, mezclando estequiométricamente los óxidos correspondientes y utilizando diferentes tipos de precursores. En particular, la conductividad térmica se calculó a partir de los valores medidos de la difusividad térmica y el calor específico (a volumen constante) utilizando la técnica fotoacústica y el método de relajación térmica, respectivamente. Aunque no se observó ninguna influencia del tipo de precursor utilizado en la preparación de la muestra sobre la conductividad térmica (k), se encontró que el valor de k depende de la temperatura de sinterización y alcanza su valor máximo para las muestras sinterizadas a 900°C, sin importar si se utilizaron precursores o no. Este artículo muestra que esta propiedad esta determinada por una combinación de los mecanismos de conducción dentro del grano con los que suceden en la frontera de grano y las características morfológicas.
]]> Descriptores: Difusividad térmica; conductividad térmica; calor específico; ferroelectromagnético; multiferroico; niobato de plomo y niobio (PFN).
PACS: 77.84.Dy; 78.20.Hp; 81.40.Rs
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Acknowledgements
This work was partially supported by projects SIP–IPN 20080032 and SEP–CONACyT 83289, 82503, and 49986–F, as well as DGAPA–UNAM projects N° IN105711 and IN107811. The support of COFAA–IPN through the PIFI and SIBE programs is also greatly acknowledged. Thanks are due to I. Gradilla for technical support.
References
]]>1. R. Ramesh and N.A. Spaldin, Nature Mater. 6 (2007) 21. [ Links ]
2. J.F. Scott, Nature Mater 6 (2007) 256. [ Links ]
3. M. Gajek et al., Nature Mater. 6 (2007) 296. [ Links ]
4. W. Eerenstein, M. Wiora, J.L. Prieto, J.F. Scott, and N.D. Mathur, Nature Mater. 6 (2007) 348. [ Links ]
5. Y.H. Chu, L.W. Martin, M.B. Holcomb, and R. Ramesh, Mater. Today 10 (2007) 16. [ Links ]
]]>6. X.S. Gao, X.Y. Chen, J. Yin, J. Wu, Z.G. Liu, and M. Wang, J Mater. Sci. 35 (2000) 5421. [ Links ]
7. O. Raymond, R. Font, N. Suárez–Almodovar, J. Portelles, and J.M. Siqueiros Ferroelectrics 294 (2003) 141. [ Links ]
8. Y. Yang, J.M. Liu, H.B. Huang, W.Q. Zou, P. Bao, and Z.G. Liu, Phys. Rev. B 70 (2004) 132101. [ Links ]
9. O. Raymond, R. Font, N. Suárez–Almodovar, J. Portelles, and J.M. Siqueiros, J. Appl. Phys. 97, 084107 (2005). [ Links ]
10. O. Raymond, R. Font, N. Suárez–Almodovar, J. Portelles, and J.M. Siqueiros, J. Appl. Phys. 97 (2005) 084108. [ Links ]
]]>11 . O. Raymond, R. Font, N. Suárez–Almodovar, J. Portelles, and J.M. Siqueiros, J. Appl. Phys. 99 (2006) 124101. [ Links ]
12. L. Yan, J. Li, C. Suchicital, and D. Viehland, Appl. Phys. Lett. 89 (2006) 132913. [ Links ]
13. D. Varshney, R.N.P. Choudhary, and R.S. Katiyar, Appl. Phys. Lett. 89 (2006) 172901. [ Links ]
14. R. Font, G. Alvarez, O. Raymond, J. Portelles, and J.M. Siqueiros, Appl. Phys. Lett. 93 (2008) 172902. [ Links ]
15. M.H. Lente et al., Phys. Rev. B 78 (2008) 054109. [ Links ]
]]>16. R. Font, O. Raymond, E. Martínez, J. Portelles, and J.M. Siqueiros, J Appl. Phys. 105 (2009) 114110. [ Links ]
17. D.P. Almond and P.M. Patel, Photothermal Science and Techniques in Physics and its Applications (Chapman and Hall, London 1996). [ Links ]
18. L.F. Perondi and L.C.M. Miranda, J. Appl. Phys. 62 (1987) 2955. [ Links ]
19. M.V. Marquezini, M.N. Cella, A.M. Mansanares, H. Vargas, and L.C.M. Miranda, Meas. Sc. Technol. 2 (1991) 396. [ Links ]
20. A.M. Mansanares, A.C. Bento, H. Vargas, N.F. Leite, and L.C.M. Miranda, Phys. Rev. B 42 (1990) 4477. [ Links ]
]]>21. H Valiente, O. Delgado–Vasallo, R Galarraga, A. Calderon, and E. Marin, International Journal of Heat Transfer 276 (2006) 1859. [ Links ]
22. J.L. Pichardo et al., Appl. Phys. A 65 (1997) 69. [ Links ]
23. M.E. Rodriguez et al., Z. Lebensm. Unters. Forsch. 200 (1995) 100. [ Links ]
24. J.A. Balderas–López et al., Forest Products Journal 46 (1996) 84. [ Links ]
25. S. Martínez etal., Journal of Materials Science 39 (2004) 1233. [ Links ]
]]>26. S. García et al., Journal de Physique IV 125 (2005) 309. [ Links ]
27. E. Marín and H. Valiente, Journal de Physique IV 125 (2005) 305. [ Links ]
28. R.E. Newnham, Properties ofMaterials: Anisotropy, Symmetry, Structure (Oxford University Press Inc., New York 2005). [ Links ]
]]>