Enhancement of Giant Dielectric Response in CaCu ₃ Ti ₄ O ₁₂ Ceramics by Zn Substitution

Abstract

Zn‐substituted CaCu 3 Ti 4 O 12 ceramics were synthesized by solid‐state sintering. Their microstructures and dielectric properties were investigated. Ca(Cu 1− x Zn x ) 3 Ti 4 O 12 single‐phase structures were obtained up to x =0.1, and the Cu + /Cu 2+ and Ti 3+ /Ti 4+ mixed‐valent structure was enhanced with increasing Zn substitution. The giant dielectric response was significantly enhanced by Zn substitution. The dielectric constant increased with increasing x , and a giant dielectric constant plateau as high as ∼9 × 10 4 was achieved for x =0.1 at 10 kHz, while that for x =0 was ∼3 × 10 4 . The enhanced giant dielectric response was profoundly concerned with the modified mixed‐valent structure.