Microstructure and Dielectric Properties of SnO₂-doped CaCu₃Ti₄O₁₂ Ceramics

Abstract

Dielectric CaCu₃Ti₄O₁₂-xSnO₂ ceramics (x = 0, 0.003, 0.006, 0.010, 0.015 and 0.020) have been synthesized by solid-state reaction method. The microstructure was studied by X-ray diffraction, Raman spectrum and Scanning electron microscope. It is revealed that SnO₂-doping results in the distortion of crystal structure and various grain growths for CaCu₃Ti₄O₁₂-based ceramics. Dielectric measurement shows that lower-doped samples (x = 0.003 and 0.006) exhibit enhanced dielectric constants which are over 70,776 and 26,406 at the range of 40-10⁴ Hz, respectively. In addition, the dielectric properties are explained in terms of internal barrier layer capacitance model by using the impedance spectroscopy analysis.

Keywords:

• CaCu₃Ti₄O₁₂ ceramics
• microstructure
• dielectric properties
• impedance spectroscopy