Modified giant dielectric properties of samarium doped CaCu3Ti4O12 ceramics

作者：Thongbai Prasit^*; Putasaeng Bundit; Yamwong Teerapon; Maensiri Santi

来源：Materials Research Bulletin, 2012, 47(9): 2257-2263.

DOI：10.1016/j.materresbull.2012.05.058

• Ceramics
• X-ray diffraction
• Dielectric properties
• Electrical properties

Effects of Sm3+ substitution on the microstructure and dielectric properties of CaCu3Ti4O12 ceramics were investigated. The grain size of CaCu3Ti4O12 ceramics was greatly decreased by doping with Sm3+, resulting from the ability of Sm3+ to inhibit the grain growth rate. This result can cause a decrease in the dielectric constant (epsilon') and loss tangent (tan delta) of CaCu3Ti4O12 ceramics. Interestingly, high dielectric permittivity (epsilon' similar to 10,863) and low loss tangent (tan delta similar to 0.043 at 20 degrees C and 1 kHz) were observed in the Ca0.925Sm0.05Cu3Ti4O12 ceramic. Nonlinear electrical properties of CaCu3Ti4O12 ceramics were modified by doping with Sm3+. The dielectric relaxation behavior of Sm-doped CaCu3Ti4O12 ceramics can be well ascribed based on the internal barrier layer capacitor model of Schottky barriers at the grain boundaries.

• 出版日期2012-9