Giant dielectric properties of CaCu3Ti4O12 ceramics synthesized by solid state reaction route

Abstract

CaCu3Ti4O12 (CCTO) ceramics were prepared by solid-state reaction route, calcination at 1050?C for 4 h and sintering at 1050 and 1100?C for 8 h. X-ray diffraction and Raman studies of the CCTO powders and sintered samples confirmed the formation of single phase cubic structure with small amount of CuO in the sintered ceramics. Scanning electron microscope study revealed the average grain size between ~6 ?m to ~29 ?m in the CCTO ceramics sintered at 1100?C. Room temperature giant dielectric constant (?r) of the order of ~105 with relatively low dielectric loss at 100Hz frequency was obtained in the CCTO ceramics sintered at 1100?C. The present study has revealed that grain size plays an important role in enhancing the dielectric properties of CCTO ceramics.