Effect of doping ion concentration on the microstructure and dielectric properties of (Na1/2Eu1/2)xCa1−xCu3Ti4O12 ceramics.

A series of single phase (Na_1/2Eu_1/2)_xCa_1−xCu₃Ti₄O₁₂ (x = 0, 0.01, 0.05, 0.1, 0.2, 0.3, 0.35, 0.4 and 0.45) ceramics with different doping amounts were successfully prepared by high temperature solid-state reaction method. The microstructure, ion valence, and dielectric properties of the ceramics were systematically studied. The results indicated that with the increase of Na⁺ and Eu³⁺ ions concentration in (Na_1/2Eu_1/2)_xCa_1−xCu₃Ti₄O₁₂ ceramics, Na and Eu elements accumulated at the grain boundaries of ceramics, thereby increasing the insulation of grain boundaries and effectively reducing the dielectric loss of the ceramics. However, the presence of Cu⁺ in (Na_1/2Eu_1/2)_xCa_1−xCu₃Ti₄O₁₂ (x ≥ 0.3) ceramics with high doping content could affect the polarization mechanism inside the ceramics and improve their dielectric properties. The dielectric constant of (Na_1/2Eu_1/2)_0.3Ca_0.7Cu₃Ti₄O₁₂ ceramics was as high as 25 282, with a dielectric loss of 0.061 (at room temperature and 10 Hz), and it had good dielectric stability. [ABSTRACT FROM AUTHOR]