Advances in materials Research

  • 제3권2호
  • /
  • Pages.105-116
  • /
  • 2014
  • /
  • 2234-0912(pISSN)
  • /
  • 2234-179X(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Cryogenic microwave dielectric properties of Mg2TiO4 ceramics added with CeO2 nanoparticles

  • Bhuyan, Ranjan K. (Department of physics, Indian Institute of Technology Guwahati) ;
  • Thatikonda, Santhosh K. (Department of physics, Indian Institute of Technology Guwahati) ;
  • Dobbidi, Pamu (Department of physics, Indian Institute of Technology Guwahati) ;
  • Renehan, J.M. (Electronics Materials Lab., School of Engineering and Physical Sciences, James Cook University) ;
  • Jacob, Mohan V. (Electronics Materials Lab., School of Engineering and Physical Sciences, James Cook University)
  • 투고 : 2014.02.10
  • 심사 : 2014.07.10
  • 발행 : 2014.06.25
⟨ 이전 논문 다음 논문 ⟩

초록

The microwave dielectric properties of $CeO_2$ nanoparticles (0.5, 1.0 & 1.5wt%) doped $Mg_2TiO_4$ (MTO) ceramics have been investigated at cryogenic temperatures. The XRD patterns of the samples were refined using the full proof program reveal the inverse spinel structure without any secondary phases. The addition of $CeO_2$ nanoparticles lowered the sintering temperature with enhancement in density and grain size as compared to pure MTO ceramics. This is attributed to the higher sintering velocity of the fine particles. Further, the microwave dielectric properties of the MTO ceramics were measured at cryogenic temperatures in the temperature range of 6.5-295 K. It is observed that the loss tangent ($tan{\delta}$) of all the samples increased with temperature. However, the $CeO_2$ nanoparticles doped MTO ceramics manifested lower loss tangents as compared to the pure MTO ceramics. The loss tangents of the pure and MTO ceramics doped with 1.5 wt% of $CeO_2$ nanoparticles measured at 6.5K are found to be $6.6{\times}10^{-5}$ and $5.4{\times}10^{-5}$, respectively. The addition of $CeO_2$ nanoparticles did not cause any changes on the temperature stability of the MTO ceramics at cryogenic temperatures. On the other hand, the temperature coefficient of the permittivity increased with rise in temperature and with the wt% of $CeO_2$ nanoparticles. The obtained lower loss tangent values at cryogenic temperatures can be attributed to the decrease in both intrinsic and extrinsic losses in the MTO ceramics.

키워드

참고문헌

  1. Belous, A., Ovchar, O., Durylin, D., Valent, M., Krzmanc, M.M. and Suvorov, D. (2007), "Microwave Composite Dielectrics Based on Magnesium Titanates", J. Euro. Ceram. Soc., 27(8), 2963-2966. https://doi.org/10.1016/j.jeurceramsoc.2006.11.022
  2. Bhuyan, R.K., Kumar, T.S., Goswami, D., James, A.R., Perumal A. and Pamu, D. (2013), "Enhanced densification and microwave dielectric properties of $Mg_2TiO_4$ ceramics added with $CeO_2$ nanoparticles", Mater. Sci. Eng. B., 178(7), 471-476. https://doi.org/10.1016/j.mseb.2012.12.014
  3. Chen, Y.B. (2012), "Dielectric properties and crystal structure of $Mg_2TiO_4$ ceramics substituting $Mg^{2+}$ with $Zn^{2+}$ and $Co^{2+}$", J. Alloys Compd., 513(5),481-486. https://doi.org/10.1016/j.jallcom.2011.10.095
  4. Ferreira, V.M., Baptista, J.L., Kamba, S. and Petzelt, J. (1993), "Dielectric spectroscopy of $MgTiO_3$-based ceramics in the $10^9-10^{14}$ Hz region", J. Mater. Sci., 28(21), 5894-5900. https://doi.org/10.1007/BF00365198
  5. Freer, R. and Azough, F. (2008), "Microstructural engineering of microwave dielectric ceramics", J. Euro. Ceram. Soc., 28(7), 1433-1441. https://doi.org/10.1016/j.jeurceramsoc.2007.12.005
  6. Ginzton, E.L. (1995), "Microwave Measurements", McGraw-Hill Book Co, New York.
  7. Huang, C.L., Chen, J.Y. and Li, B.J. (2010), "A new dielectric material system using (1-x) $(Mg_{0.95}Co_{0.05})_2TiO_{4}$-x $Ca_{0.8}Sm_{0.4/3}TiO_3$ at microwave frequencies", Mater. Chem. Phys., 120(1), 217-220. https://doi.org/10.1016/j.matchemphys.2009.10.050
  8. Jacob, M.V. (2005), "Low temperature microwave characteristics of lithium fluoride at different frequencies," Sci. Technol. Adv. Mater., 6(8), 944-949. https://doi.org/10.1016/j.stam.2005.07.009
  9. Jacob, M.V., Mazierskaa, J., Ledenyova, D. and Krupka, J. (2003), " Microwave characterisation of CaF2 at cryogenic temperatures using a dielectric resonator technique", J. Euro. Ceram. Soc., 23(14), 2617-2622. https://doi.org/10.1016/S0955-2219(03)00183-3
  10. Jacob, M.V., Hartnett, J.G., Mazierska, J., Krupka, J. and Tobar, M.E. (2006), "Dielectric characterisation of barium fluoride at cryogenic temperatures using TE011 and quasi TE0mn mode dielectric resonators", Cryogenics, 46(10), 730-735. https://doi.org/10.1016/j.cryogenics.2006.06.004
  11. Jacob, M.V., Mazierska, J., Leong, K. and Krupka, J. (2001), "Simplified method for measurements and calculations of coupling coefficients and $Q_0$ factor of high temperature super conducting dielectric resonators", IEEE Trans. Micro. Theory Tech.., 49(12), 2401-2407. https://doi.org/10.1109/22.971627
  12. Jacob, M.V., Pamu, D. and James Raju, K.C. (2007), "Cryogenic microwave dielectric properties of sintered $(Zr_{0.8}Sn_{0.2})TiO_4$ doped with CuO and ZnO", J. Am. Ceram. Soc., 90(5), 1511-1514. https://doi.org/10.1111/j.1551-2916.2007.01638.x
  13. Kuang, X., Jing, X. and Tang, Z. (2006), "Dielectric loss spectrum of $MgTiO_3$ investigated by AC impedance and microwave resonator measurements", J. Am. Ceram. Soc., 89(1), 241-246. https://doi.org/10.1111/j.1551-2916.2005.00669.x
  14. Pamu, D., Narayana Rao, G.L., Raju James, K.C. and Jacob, M.V. (2007), "Effect of CuO on the sintering and cryogenic microwave characteristics of $(Zr_{0.8}Sn_{0.2})TiO_4$ ceramics", Sci. Technol. Adv. Mater., 8(6), 469-476. https://doi.org/10.1016/j.stam.2007.07.006
  15. Penn, S.J., Alford, N.M., Templeton, A., Wang, X., Xu, M., Reece, M. and Schrapel, K. (1997), "Effect of porosity and grain size on the microwave dielectric properties of sintered alumina", J. Am. Ceram. Soc., 80(7), 1885-1888.
  16. Reaney, I.M. and Iddles, D. (2006), "Microwave dielectric ceramics for resonators and filters in mobile phone networks", J. Am. Ceram. Soc., 89(7), 2063-2072.
  17. Subodh, G., Ratheesh, R., Jacob, M.V. and Sebastian, M.T. (2008), "Microwave dielectric properties and vibrational spectroscopic analysis of $MgTe_2O_5$ ceramics", J. Mater. Res., 23(6), 1551-1556. https://doi.org/10.1557/JMR.2008.0212
  18. Wakino, K., Murata, M. and Tamura, H. (1986), "Far infrared reflection spectra of Ba (Zn,Ta) $O_3-BaZrO_3$ dielectric resonator material," J. Am. Ceram. Soc., 69(1), 34-37. https://doi.org/10.1111/j.1151-2916.1986.tb04689.x