Preparation and Structure of Ba₂Ti₉O₂₀ and BaTi₄O₉ Ceramics Derived from Sol-Gel Powders

Abstract:

Ba2Ti9O20 (B2T9) and BaTi4O9 (BT4) ceramics have been fabricated using sol-gel technique. The sol-gel derived powder was produced from barium acetate and butyl titanate using acetic acid as solvent. The as-prepared powders were then calcined at different temperatures ranging from 600° to 1200°C. After that, the powder was pressed into pellets and further sintered at different temperatures ranging from 1250°C to 1380°C. XRD characterization and Raman spectroscopy showed that after calcining the sol-gel powder at 900°C for 2 h and sintering the pressed pellets at 1330°C for 4 h, triclinic B2T9 and orthorhombic BT4 ceramics could be obtained. The dielectric constant and Q-value are 35 and 1910 at 6.1 GHz.

• Periodical: Key Engineering Materials (Volumes 280-283)
• Pages: 47-52
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.280-283.47
• Online since: February 2007
• Authors: Sheng Guo Lu, Haydn Chen, C.L. Mak, K.H. Wong, H.W.L. Chan, C.L. Choy
• Keywords: Ba₂Ti₉O₂₀, BaTi₄O₉, Microwave Dielectrics, Sol-Gel Process

References

[1] Y. H. Xu and J. D. Mackenzie, Integr. Ferroelectr. Vol. 1 (1992), p.17.

[2] E. K. Akdogan, M. R. Leonard and A, Safari, Size effects in ferroelectric ceramics, pp.61-112.

[3] S. G. Lu, C. L. Mak, and K. H. Wong, J. Am. Ceram. Soc. Vol. 84 (2001), p.79.

[4] I. -W. Chen and X. -H. Wang, Nature, Vol. 404 (2000), p.168.

[5] K. P. Kumar, K. Keizer, A. J. Burggraaf, T. Okubo, H. Nagamoto & S. Morooka, Nature, Vol. 358 (1992), p.48.

DOI: 10.1038/358048a0

[6] H. M. O'Bryan, Jr., J. Thomson, Jr. and J. K. Plourde, J. Am. Ceram. Soc. Vol. 57 (1974), p.450.

[7] H. M. O'Bryan and Jr., J. Thomson, ibid. Vol. 57 (1974), p.522.

[8] H. M. O'Bryan and Jr., J. Thomson, ibid. Vol. 66 (1983), p.66.

[9] K. Wakino, K. Minai, and H. Tamura, ibid. Vol. 67 (1984), p.278.

[10] P. K. Davies, J. Z. Tong, and T. Negas, ibid. Vol. 80 (1997), p.1727.

[11] R. J. Cava, J. Mater. Chem. Vol. 11 (2001), p.54.

[12] S. Nomura, K. Toyama, K. Kaneta, Jpn. J. Appl. Phys. Vol. 21 (1982), pp. L624.

[13] S. I. Hirano, K. Yokouchi, M. Arai and S. Naka, Advances in Ceramics, Vol. 19 (1986), p.139.

[14] H. C. Lu, L. E. Burkhart and G. L. Schrader, J. Am. Ceram. Soc. Vol. 74 (1991), p.968.

[15] Y. B. Xu, X. M. Chen, and L. B. Wang, ibid. Vol. 84 (2001), p.669.

[16] M. Cernea, E. Chirtop, D. Neacsu, I. Pasuk, and S. Iordanescu, ibid. Vol. 85 (2002), p.499.

DOI: 10.1111/j.1151-2916.2002.tb00122.x

[17] J. Javadpour and N. G. Eror, ibid., Vol. 71 (1988), p.206.

[18] S. G. Lu, K. W. Kwok, H. L. W. Chan and C. L. Choy, Mater. Sci. & Eng. B Vol. 99 (2003), p.491.