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Synthesis and Dielectric Properties of CaCu3Ti4O12 Doped with La3+

A.K. Thomas

Abstract


The effect La3+ doping on the structural and dielectric properties of CaCu3Ti4O12 (CCTO) is investigated, resulting in a compound of the type Ca1-xLaxCu3Ti4O12 (x = 0.00, 0.20 and 0.50). The compounds have been prepared by conventional solid state reaction. The Ca1-xLaxCu3Ti4O12 ceramics were characterized by X-ray diffraction, SEM techniques. The grain size and the grain boundary resistivity increased with the increase of doping percentages. Dielectric constant of the samples decreases with increasing dopant concentrations. The dielectric behaviour of compound can be explained in terms of barrier layer capacitor mechanism.


Keywords


Dielectric properties, solid state reaction, Perovskites, grain boundaries, CCTO

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References


1. Renner B, Lunkenheimer P, Schetter M, Loidl A, Reller A, Ebbinghaus SG.. Dielectric behaviour of copper tantalum oxide. Journal of Applied Physics. 2004;96(8):4400–4404.

MA Subramanian, L Dong, N Duan, BA Reisner, AW Sleight. High Dielectric Constant in ACu3Ti4O12 and ACu3Ti3FeO12 Phases. J. Solid State Chem. 2000;151:323–25p.

Homes CC, Vogt T, Shapiro SM, Wakimoto S, Ramirez AP. Optical response of high-dielectric-constant perovskite-related oxide. Science. 2001;293(5530):673–676.

Ramirez AP, Subramanian MA, Gardel M, Blumberg G, Li D, Vogt T. ShapiroS.M.. Giant dielectric constant response in a copper-titanate. Solid State Communications. 2000;115(5):217–220.

Jin S, Xia H, Zhang Y.. Effect of La-doping on the properties of CaCu3Ti4O12 dielectric ceramics. Ceramics International. 2009;35(1):309–313.

Yu H, Liu H, Hao H, Luo D, Cao M. Dielectric properties of CaCu3Ti4O12 ceramics modified by SrTiO3. Materials Letters. 2008;62(8–9):1353–1355.

Kobayashi W, Terasaki I. CaCu3Ti4O12∕CaTiO3 composite dielectrics: Ba∕ Pb-free dielectric ceramics with high dielectric constants. Applied Physics Letters. 2005;87(3):032902.

Sinclair DC, Adams TB, Morrison FD and West AR. CaCu3Ti4O12: one-step internal barrier layer capacitor. Applied Physics Letters. 2002;80(12):2153–2155.

Adams TB, Sinclair DC, West AR. Giant barrier layer capacitance effects in CaCu3Ti4O12 ceramics. Advanced Materials. 2002;14(18):1321–1323.

Chung SY, Kim ID, Kang SJL. Strong nonlinear current–voltage behaviour in perovskite-derivative calcium copper titanate. Nature Materials. 2004;3(11):774.

Li J, Sleight AW, Subramanian MA. Evidence for internal resistive barriers in a crystal of the giant dielectric constant material: CaCu3Ti4O12. Solid State Communications. 2005;135(4):260–262.

Wu L, Zhu Y, Park S, Shapiro S, Shirane G, Tafto J. Defect structure of the high-dielectric-constant perovskite CaCu3Ti4 O 12. Physical Review B. 2005;71(1):014118.

Cohen MH, Neaton JB, He L, Vanderbilt D.. Extrinsic models for the dielectric response of CaCu3Ti4O12. Journal of Applied Physics. 2003;94(5):3299–3306.

Liu J, Duan CG, Yin WG, Mei WN, Smith RW, Hardy JR. Large dielectric constant and Maxwell-Wagner relaxation in Bi 2∕ 3 Cu3Ti4O12. Physical Review B. 2004;70(14):144106.

Li W, Schwartz RW. Maxwell-Wagner relaxations and their contributions to the high permittivity of calcium copper titanate ceramics. Physical Review B. 2007;75(1):012104.

Mu CH, Liu P, He Y, Zhou JP, Zhang HW. An effective method to decrease dielectric loss of CaCu3Ti4O12 ceramics. Journal of Alloys and Compounds. 2009;471(1–2):137–141.

Feng L, Tang X, Yan Y, Chen X, Jiao Z, Cao G. Decrease of dielectric loss in CaCu3Ti4O12 ceramics by La doping. Physica Status Solidi (a). 2006;203(4):R22-R24.

Hong SH, Kim DY, Park HM and Kim YM,. Electric and dielectric properties of Nb‐doped CaCu3Ti4O12 ceramics. Journal of the American Ceramic Society. 2007;90(7):2118–2121.


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