Dielectric properties and microstructure of CaCu3Ti4-xMnxO12 ceramics

In this work, we have reported the dielectric properties and microstructure of the Mn doped CaCu3Ti4O12 (CCTO) ceramics. The conventional solid-state reaction was employed. By the partial Mn -for Ti substitution, the dielectric loss was suppressed remarkably while the dielectric constant (εr) still remains high. The sample CaCu3Ti3.76Mn0.24O12 exhibits a high εr over 1200 and a low dielectric loss below 0.06 at room temperature. Furthermore, the εr value of this sample shows rather independent with temperature. SEM micrographs show that the sample is dense (≥ 90% of theoretical density) and the grain size of the samples was gradually reduced with increasing x. This CaCu3Ti4-xMnxO12 system is believed to be a promising candidate for capacitor applications.