Microstructure and Improved Dielectric Properties of CaCu 3Ti 4O 12 Ceramics by Lanthanum/Europium Co-Doping

In this work, (La, Eu) co-doped CaCu3Ti4O12 ceramics (Ca1-xLaxCu3Ti4-xEuxO12, x = 0.1, 0.3, and 0.5) were prepared by the traditional solid-state method. The XRD results of ceramics confirmed the formation of the single-phase CCTO and a residual amount of CaTiO3. The refined calculation found that the lattice constant of CLCTEO ceramics will be significantly increased due to the co-doping of La and Eu. The FESEM analysis showed a smaller grain size for the co-doped CCTO. Impedance measurements indicated that the (La, Eu) co-doped CCTO ceramics have higher dielectric permittivity than the single-doped with La and Eu. The most negligible dielectric loss was achieved in CLCTEO ceramics with x = 0.1, and a low tanδ of 0.013 was observed at 800kHz for room temperature. The results indicated that the co-doping method is an effective method to improve the dielectric properties.