Influence of indium and niobium co-doping on the dielectric and impedance properties of SrSnO3 ceramics

Structure, dielectric and impedance properties of SrSnO3 ceramics co-doped with In3+ and Nb5+ ions (Sr(In0.5Nb0.5)xSn1-xO3), obtained by the solid-state method and sintering at 1550°C, were investigated. In the range of x = 0-0.1, the substitution of Sn4+ by In3+ and Nb5+ ions at B-site did not affect the crystal structure of these ceramics significantly. A high dielectric permittivity (> 1.0 × 104) and low dielectric loss (< 0.2) were demonstrated at the optimal doping concentration of x = 0.04. The dielectric loss displayed distinct relaxation peaks, which shifted towards lower frequencies as the doping concentration increased. Impedance and electric modulus measurements confirmed the different relaxation processes. Our results provide insight into the role of donor and acceptor co-doping on the properties of SrSnO3 ceramics, which is important for their use in dielectric and energy storage applications.