Microstructure and electrical properties of CaCu3Ti4O12 ceramics

CaCu3Ti4O12 (CCTO) ceramics are prepared by the conventional solid-state reaction method under various sintering temperatures from 1000to1120°C at an interval of 10°C. Microstructures and crystalline structures are examined by scanning electronic microscopy and x-ray diffraction, respectively. Dielectric properties and complex impedances are investigated within the frequency range of 40Hz–110MHz over the temperature region from room temperature to 350°C. It has been disclosed that the microstructures can be categorized into three different types: type A (with the small but uniform grain sizes), type B (with the bimodal distribution of grain sizes) and type C (with the large and uniform grain sizes), respectively. The largeness of low-frequency dielectric permittivity at room temperature is closely related to the microstructure. Ceramics with different types of microstructures show the diverse temperature-dependent behaviors of electrical properties. However, the existence of some common characteristics is...

[1]  M. Shen,et al.  The electrode/sample contact effects on the dielectric properties of the CaCu3Ti4O12 ceramic , 2005 .

[2]  M. Pan,et al.  A Bimodal Grain Size Model for Predicting the Dielectric Constant of Calcium Copper Titanate Ceramics , 2005 .

[3]  Sung-Yoon Chung,et al.  Lattice distortion and polarization switching in calcium copper titanate , 2005 .

[4]  Lei Zhang.  Electrode and grain-boundary effects on the conductivity of CaCu3Ti4O12 , 2005 .

[5]  A. Sleight,et al.  Evidence for internal resistive barriers in a crystal of the giant dielectric constant material: CaCu3Ti4O12 , 2005 .

[6]  Jia-liang Zhang,et al.  Grain boundary effect on the dielectric properties of CaCu3Ti4O12 ceramics , 2005 .

[7]  M. Pan,et al.  The effect of processing on the giant dielectric properties of CaCu3Ti4O12 , 2005 .

[8]  T. Fang,et al.  Mechanism for Developing the Boundary Barrier Layers of CaCu3Ti4O12 , 2005 .

[9]  G. Shirane,et al.  Defect structure of the high-dielectric-constant perovskite Ca Cu 3 Ti 4 O 12 , 2004, cond-mat/0412711.

[10]  Sergei V. Kalinin,et al.  Real space imaging of the microscopic origins of the ultrahigh dielectric constant in polycrystalline CaCu3Ti4O12 , 2004, cond-mat/0407608.

[11]  D. Capsoni,et al.  Role of doping and CuO segregation in improving the giant permittivity of CaCu3Ti4O12 , 2004 .

[12]  Lei Zhang,et al.  Polaron relaxation and variable-range-hopping conductivity in the giant-dielectric-constant material Ca Cu 3 Ti 4 O 12 , 2004 .

[13]  Il-Doo Kim,et al.  Strong nonlinear current–voltage behaviour in perovskite-derivative calcium copper titanate , 2004, Nature materials.

[14]  D. Capsoni,et al.  Electric and dielectric properties of pure and doped CaCu3Ti4O12 perovskite materials , 2004 .

[15]  P. Lunkenheimer,et al.  Nonintrinsic origin of the colossal dielectric constants in Ca Cu 3 Ti 4 O 12 , 2004, cond-mat/0403119.

[16]  F. Morrison,et al.  Novel high capacitance materials:- BaTiO3:La and CaCu3Ti4O12 , 2004 .

[17]  Lixin He,et al.  Extrinsic models for the dielectric response of CaCu3Ti4O12 , 2003, cond-mat/0304196.

[18]  Derek C. Sinclair,et al.  Giant Barrier Layer Capacitance Effects in CaCu3Ti4O12 Ceramics , 2002 .

[19]  A. A. Volkov,et al.  Origin of apparent colossal dielectric constants , 2002 .

[20]  F. Morrison,et al.  CaCu3Ti4O12: One-step internal barrier layer capacitor , 2002 .

[21]  R. Shaw,et al.  Range shifts and adaptive responses to Quaternary climate change. , 2001, Science.

[22]  Margaret L. Gardel,et al.  Giant dielectric constant response in a copper-titanate , 2000 .

[23]  Arthur W. Sleight,et al.  High Dielectric Constant in ACu3Ti4O12 and ACu3Ti3FeO12 Phases , 2000 .

[24]  S. R. Elliott,et al.  A.c. conduction in amorphous chalcogenide and pnictide semiconductors , 1987 .