A novel strategy to enhance dielectric performance and non-Ohmic properties in Ca2Cu2−xMgxTi4O12

Abstract

Abstract A novel strategy to improve the dielectric and non-Ohmic properties of CaCu 3 Ti 4 O 12 ceramics that deliberately created a binary-phase system of CaCu 3− x Mg x Ti 4 O 12 /CaTiO 3 was proposed and can be performed with a starting nominal formula of Ca 2 Cu 2− x Mg x Ti 4 O 12 . Mg 2+ doping ions were preferentially incorporated only into the CaCu 3 Ti 4 O 12 phase. Substitution of Mg 2+ into CaCu 3 Ti 4 O 12 /CaTiO 3 can cause a significant increase in dielectric permittivity and a large reduction of the loss tangent to 3− x Mg x Ti 4 O 12 /CaTiO 3 ceramics. Degradation of nonlinear properties with increased sintering time is suggested to be the result of the dominant effect of oxygen vacancies. Impedance spectroscopy analysis demonstrated that improved dielectric and nonlinear properties could be attributed to the enhanced electrical responses of CaCu 3 Ti 4 O 12 –CaTiO 3 and CaCu 3 Ti 4 O 12 –CaCu 3 Ti 4 O 12 interfaces resulting from Mg 2+ doping ions.