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Crystal Structure, Raman Spectra and Dielectric Properties of Ca0.66Ti0.66La0.34Al0.34O3 Microwave Ceramics with Nd3+Additions
Y. Xu, R. Fu, Y. Yang, J. Cai, X. Gu, J. Fang
College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 210016, Nanjing, Jiangsu
received January 3, 2016, received in revised form February 22, 2016, accepted April 13, 2016
Vol. 7, No. 3, Pages 257-262 DOI: 10.4416/JCST2016-00001
Abstract
Ca0.66Ti0.66La0.34Al0.34O3 (CTLA) ceramics doped with Nd2O3 were prepared by means of the conventional solid-state reaction method. The Nd2O3 dopant was added in the range of 0.5 – 3.5 wt%. The dielectric properties, crystal structure and Raman spectra of the CTLA ceramics doped with Nd2O3 were investigated with the Hakki and Coleman's dielectric resonant, XRD and Raman spectroscopy method, respectively. It was found that Nd2O3 promotes the densification and enlarges the crystal cell volume of CTLA ceramics. Two chemical reaction defects emerge in CTLA ceramics with the substitution of Nd3+. Nd3+ is substituted for La/Ca atoms at the A-sites of the CTLA ceramics' structure with increasing Nd2O3 doping, and the polarization of the TiO6 octahedra reaches the maximum volume when the amount of Nd2O3 doping is 2.0 wt%. Excellent microwave dielectric properties of Q×f= 37454 GHz (@4 GHz), εr = 45 and τf = 0.13 ppm/°C were obtained for CTLA ceramics with the addition of 2.0 wt% Nd2O3.
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Keywords
Ca0.66Ti0.66La0.34Al0.34O3, microwave dielectric properties, structure, additives
References
1 Zhang, X., Zhang, Y., Zhang, J., Peng, B., Xie, Z., Yuan, L., Yue, Z., Li, L.: Microwave dielectric properties and thermally stimulated depolarization currents study of (1-x)Ba0.6Sr0.4La4Ti4O15–xTiO2 ceramics, J. Am. Ceram. Soc., 97, 3170 – 3176, (2014).
2 Ma, P.P., Yi, L., Liu, X.Q., Li, L., Chen, X.M.: Effects of mg substitution on Order/Disorder transition, microstructure, and microwave dielectric characteristics of Ba((Co0.6Zn0.4)1/3Nb2/3)O3 Complex perovskite ceramics, J. Am. Ceram. Soc., 96, 1795 – 1800, (2013).
3 Yao, G., Liu, P., Zhang, H.: Low-temperature sintering and microwave dielectric properties of (Mg0.95Zn0.05)2(Ti0.8Sn0.2)O4– (Ca0.8Sr0.2)TiO3 Composite ceramics, J. Am. Ceram. Soc., 96, 3114 – 3119, (2013).
4 Ghosh, B., Halder, S., Sinha, T.P.: Dielectric relaxation and collective vibrational modes of double-perovskites A2SmTaO6 (A = ba, sr and Ca), J. Am. Ceram. Soc., 97, 2564 – 2572, (2014).
5 Guo, J., Zhou, D., Zou, S.-L., Wang, H., Pang, L.-X., Yao, X.: Microwave dielectric ceramics Li2MO4-TiO2 (M = Mo, W) with low sintering temperatures, J. Am. Ceram. Soc., 97, 1819 – 1822, (2014).
6 Su, C., Fang, W., Wei, Z., Tang, Y., Fang, L.: Microwave dielectric properties of MLi2Ti6O14 [M=Ba and Sr] ceramics and their compatibility with sliver, J. Am. Ceram. Soc., 97, 3740 – 3743, (2014).
7 Kipkoecha, E.R., Azough, F., Freer, R., Leach, C.,Thompson, S.P., Tang, C.C.: Structural study of Ca0.7Nd0.3Ti0.7Al0.3O3 dielectric ceramics using synchrotron X-ray diffraction, J. Eur. Ceram. Soc., 23, 2677 – 2682, (2003).
8 Jancar, B., Suvorov, D., Valant, M., Drazic, G.: Characterization of CaTiO3-NdAlO3 dielectric ceramics, J. Eur. Ceram. Soc., 23, 1391 – 1400, (2003).
9 Pashkin, A., Kamba, S., Berta, M., Petzelt, J., Csete de Gyorgyfalva, G.D.C., Zheng, H., Bagshaw, H., Reaney, I.M.: High frequency dielectric properties of CaTiO3-based microwave ceramics, J. Phys. D: Appl. Phys., 38, 741 – 748, (2005).
10 Khalyavin, D.D., Salak, A.N., Senos, A.M.R. et al.: Structure sequence in the CaTiO3-LaAlO3 microwave ceramics – revised, J. Am. Ceram. Soc., 89, [5], 1721 – 1723, (2006).
11 Pang, L.-X., Zhou, D., Guo, J., Yue, Z.-X., Yao, X.: Microwave dielectric properties of (Li0.5Ln0.5)MoO4 (Ln = Nd, Er, Gd, Y, Yb, Sm, and Ce) ceramics, J. Am. Ceram. Soc., 98, 130 – 135, (2015).
12 Nenasheva, E.A., Mudroliubova, L.P., Kartenko, N.F.: Microwave dielectric properties of ceramics based on CaTiO3-LnMO3 system (Ln-La, Nd; M-Al, Ga), J. Eur. Ceram. Soc., 23, 2443 – 2448, (2003).
13 Suvorov, D., Valant, M., Jancar, B. et al.: CaTiO3-based ceramics: microstructural development and dielectric properties, Acta Chim.Slov., 48, [1], 87 – 100. (2001).
14 Zhang, J., Yue, Z., Zhou, Y., Zhang, X., Li, L.: Microwave dielectric properties and thermally stimulated depolarization currents of (1 – x)MgTiO3–xCa0.8Sr0.2TiO3Ceramics, J. Am. Ceram. Soc., 98, 1548 – 1554, (2015).
15 Ravi, G.A., Azough, F., Freer, R.: Effect of Al2O3 on the structure and microwave dielectric properties of Ca0.7Ti0.7 La0.3Al0.3O3, J. Eur. Ceram. Soc., 27, 2855 – 2859, (2007).
16 Zhou, Y., Meng, S., Wu, H., Yue, Z.: Microwave dielectric properties of Ba2Ca1-xSrxWO6 double perovskites, J. Am. Ceram. Soc., 94, 2933 – 2938, (2011).
17 Zhang, S.L., Ma, P.P., Liu, X.Q., Chen, X.M.: Structure and microwave dielectric characteristics of Ca[(Ga1/2Nb1/2)1-xTix]O3 ceramics, J. Am. Ceram. Soc., 98, 3185 – 3191, (2015).
18 Shannon, R.D.: Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides, Acta. Cryst., A32, 751 – 767, (1976).
19 Huang, J., Zhou, D.X., Hu, M.Z., Wang, H. :The preliminary study of the improvement principle of Ln rare earth element on microwave dielectric ceramics, J. Huazhong Univ. Sci., 33, [2], 19 – 21.
20 Lowndes, R., Azough, F., Cernik, R., Freer, R.: Structures and microwave dielectric properties of Ca(1-x)Nd2x/3TiO3 ceramics, J. Eur. Ceram. Soc., 32, 3791 – 3799, (2012).
21 Xi, H.H., Zhou, D., Xie, H.-D., He, B., Wang, Q.-P.: Raman spectra, infrared spectra, and microwave dielectric properties of low-temperature firing [(Li0.5Ln0.5)1-xCax]MoO4 (Ln = sm and Nd) solid solution ceramics with scheelite structure, J. Am. Ceram. Soc., 97, 587 – 593, (2014).
22 Dias, A., Lage, M.M., Khalam, L.A., Sebastian, M.T., Moreira, R.L.: Vibrational spectroscopy of Ca2LnTaO6 (Ln = lanthanides, Y, and In) and Ca2InNbO6 double perovskites, Chem. Mater., 23, 14 – 20, (2011).
23 Dias, A., Khalam, L.A., Sebastian, M.T., Lage, M.M., Matinaga, F.M., Moreira, R.L.: Raman scattering and infrared spectroscopy of chemically substituted Sr2LnTaO6 (Ln) lanthanides, Y, and In) double perovskites, Chem. Mater., 20, 5253 – 5259, (2008).
24 Kaminskii A.A.: Achievements in the field of physics and spectroscopy of activated laser crystals, Phys. Status Solidi A, 87, 11 – 57, (1985).
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