Effects of Cu ion implantation on the microstructure, dielectric and impedance properties of SrTiO3 ceramics prepared by reduction-reoxidation method

SrTiO3 ceramic samples were successfully prepared using an innovative approach that combined ion implantation technique with the reductive-reoxidation sintering method. SrTiO3 ceramics were reductively sintered in N2 and H2 atmosphere, and Cu ion implanted, followed by thermal oxidation treatment in air. Experimental results demonstrate a notable reduction in dielectric loss while achieving a colossal permittivity (epsilon = 41,444 at kHz, tans = 0.054 at 1 kHz). The phase structure, micromorphology, element valence state, dielectric properties and AC impedance spectrum characteristics of SrTiO3 ceramic materials were studied, and the mechanism of dielectric properties was explained using the Internal Barrier Layer Capacitor (IBLC) effects. Research results show that Cu ion implantation, oxygen vacancies at ceramic grain boundaries, and oxygen adsorption during reoxidation thermal treatment play a key role in reducing the dielectric loss of the material.