Microstructure and dielectric properties of CaCu3Ti4O12 ceramics by lanthanum/europium co-doping

In this work, (La, Eu) co-doped CaCu3Ti4O12 ceramics (Ca1-xLaxCu3Ti4-xEuxO12 (CLCTEO)), x = 0.1, 0.3, and 0.5) were prepared by the solid-state method. The phase structure, morphologies, dielectric properties, and impedance spectrum were investigated methodically. The XRD of CLCTEO ceramics confirmed the formation of the complex perovskite with a residual amount of CaTiO3. The refined calculation found that the lattice parameter of CLCTEO ceramics will significantly increase due to the co-doping of La and Eu. The FESEM analysis shows that the grain size of co-doped CCTO is smaller, reaching the nanometer scale. Impedance indicates that the (La, Eu) co-doped CCTO ceramics have higher dielectric permittivity than the single-doped with La or Eu. The results show that co-doping is an effective method to improve the dielectric properties of CCTO ceramics.