Dielectric Properties of CaCu₃Ti₄O₁₂/Al₂O₃ Composites

Abstract:

In this work, (1-x)CaCu₃Ti₄O₁₂/xAl₂O₃ (x = 0, 0.01, 0.03, 0.05 and 0.1) composite samples were prepared by the conventional solid-state reaction method. The dielectric properties of the samples were investigated at frequency range of 20 – 10⁶ Hz. X-ray diffractogram results show that the samples with Al₂O₃ sintered at 1040 °C/10 h are mixed phase and consist of CaCu₃Ti₄O₁₂, CuAl₂O₄, TiO₂ and Al₂O₃. The average grain size of the samples increased greatly for x = 0.01, then abruptly depressed for x ≥ 0.03. Al₂O₃-added (x = 0.01) has been shown to increase the dielectric permittivity (ε’) up to ~5000 over frequency range of 10² – 10⁵ Hz, while retaining the dielectric loss (tan δ ~ 0.15) at 1 kHz. With further increase of Al₂O₃ content, the ε’ and tan δ values of the samples are decreased monotonically in all frequency ranges. The improvement of dielectric properties in the composite sample was attributed to the enhanced grain boundary resistance.

• Periodical: Materials Science Forum (Volume 888)
• Pages: 12-16
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.888.12
• Online since: March 2017
• Authors: Mohamad Johari bin Abu, Rosyaini Afindi Zaman, Mohd Fariz Ab Rahman, Mohsen Ahmadipour, Julie Juliewatty Mohamed, Mohd Fadzil Ain, Zainal Arifin Ahmad*
• Keywords: Composite Ceramics, Dielectric Properties, Microstructure

References

[1] C.C. Homes, T. Vogt, S.M. Shapiro, S. Wakimoto, A.P. Ramirez, Optical response of high-dielectric-constant perovskite-related oxide, Science 293(5530) (2001) 673-676.

DOI: 10.1126/science.1061655

[2] M.A. Subramanian, L. Dong, N. Duan, B.A. Reisner, A.W. Sleight, High dielectric constant in ACu3Ti4O12 and ACu3Ti3FeO12 phases, J. Solid State Chem. 151(2) (2000) 323-325.

DOI: 10.1006/jssc.2000.8703

[3] S.D. Hutagalung, M.I. M Ibrahim, Z.A. Ahmad, Microwave assisted sintering of CaCu3Ti4O12, Ceram. Int. 34 (4)(2008) 939-942.

DOI: 10.1016/j.ceramint.2007.09.074

[4] M.H. Cohen, J.B. Neaton, L. He, D. Vanderbilt, Extrinsic models for the dielectric response of CaCu3Ti4O12, J. Appl. Phys. 94(5) (2003) 3299-3306.

DOI: 10.1063/1.1595708

[5] J. Li, K. Wu, R. Jia, L. Hou, L. Gao, S. Li, Towards enhanced varistor property and lower dielectric loss of CaCu3Ti4O12 based ceramics, Mater. Des. 92 (2016) 546-551.

DOI: 10.1016/j.matdes.2015.12.073

[6] J. Boonlakhorn, B. Putasaeng, P. Kidkhunthod, P. Thongbai, Improved dielectric properties of (Y+Mg) co-doped CaCu3Ti4O12 ceramics by controlling geometric and intrinsic properties of grain boundaries, Mater. Des. 92 (2016) 494-498.

DOI: 10.1016/j.matdes.2015.12.042

[7] M.F. Ab Rahman, S.D. Hutagalung, Z.A. Ahmad, M.F. Ain, J.J. Mohamed, The effect of different dopant site (Cu and Ca) by magnesium on CaCu3Ti4O12 dielectric properties, J. Mater. Sci.: Mater. Electron. 26(6) (2015) 3947-3956.

DOI: 10.1007/s10854-015-2929-z

[8] A. Rajabtabar-Darvishi, R. Bayati, O. Sheikhnejad-Bishe, L.D. Wang, W.L. Li, J. Sheng, W.D. Fei, Giant dielectric response and low dielectric loss in Al2O3 grafted CaCu3Ti4O12 ceramics, J. Appl. Phys. 117(9) (2015) 094103.

DOI: 10.1063/1.4914052

[9] R. Jia, X. Zhao, J. Li, X. Tang, Colossal breakdown electric field and dielectric response of Al-doped CaCu3Ti4O12 ceramics, Mater. Sci. Eng. B 185(1) (2014) 79-85.

DOI: 10.1016/j.mseb.2014.02.015

[10] S.W. Choi, S.H. Hong, Effect of Al doping on the electric and dielectric properties of CaCu3Ti4O12, J. Am. Ceram. Soc. 90(12) (2007) 4009-4011.

[11] C. Puchmark, G. Rujijanagul, Improvement in dielectric and mechanical performance of CaCu3. 1Ti4O12. 1 by addition of Al2O3 nanoparticles, Nanoscale Res. Lett. 7(1) (2012) 68.

DOI: 10.1186/1556-276x-7-68

[12] P.K. Jena, E.A. Brocchi, I.G. Solorzano, M.S. Motta, Identification of a third phase in Cu–Al2O3 nanocomposites prepared by chemical routes, Mater. Sci. Eng. A 371(1-2) (2004) 72-78.

DOI: 10.1016/s0921-5093(03)00642-7

[13] M.J. Abu, J.J. Mohamed, M.F. Ain, Z.A. Ahmad, Phase structure, microstructure and broadband dielectric response of Cu nonstoichiometry CaCu3Ti4O12 ceramic, J. Alloys Comp. 683 (2016) 579-589.

DOI: 10.1016/j.jallcom.2016.04.318