LAUSR

Abstract Giant permittivity was performed in CdCu 3 Ti 4 O 12 ceramics separately fabricated via the sol-gel technique (SG) and the standard solid-state technique (SS). XRD patterns and Raman spectrums revealed that CdCu 3 Ti 4 O 12 ceramics with single perovskite-related crystal phase were obtained irrespective of the preparation processing. TG-DSC, XRD, and FT-IR were carried out to explore the formation temperature of crystal phases as well as reaction mechanisms. The results indicated that the phase formation temperature of CdCTO-SG powders is at least 100 °C lower than that of CdCTO-SS powders and the dielectric properties of the CdCTO-SG ceramics are superior to those of the CdCTO-SS ceramics. In addition, three abnormal dielectric peaks were observed in dielectric temperature spectrum regardless of the two methods. Besides, data acquired from impedance and modulus assessments indicated that Maxwell-Wagner polarization contributed to the dielectric responses of samples. Therefore, giant dielectric properties of CdCu 3 Ti 4 O 12 ceramics conformed to internal barrier layer capacitor (IBLC) effect. Semiconducting grains are closely associated with the presence of mixed valence states of Cu + /Cu 2+ and Ti 3+ /Ti 4+ in samples.