Effect of Interfaces on Dielectric Relaxation in La0.35Sr0.6MnO3 -YSZ

Abstract

The perovskite structure material La _0.35 Sr _0.6 MnO ₃ was sintered in air and the mixed ceramic of a _0.35 Sr _0.6 MnO ₃ and 8 mol % Y ₂ O ₃ +ZrO ₂ with a 1:1 mass rate was also sintered in air, both at 1530 K for 12 hour. The AC complex impedance spectra have been measured and the effect of the interface between La _0.35 Sr _0.6 MnO ₃ and YSZ on dielectric relaxation properties of La _0.35 Sr _0.6 MnO ₃ has been investigated. A schematic of diffusion phase formation and the equivalent circuits are proposed for explaining the results. In the complex impedance spectra, the first and second semicircles correspond to the grain-boundary and interface respectively. The results show that the dielectric relaxation properties and structure of the mixed ceramic are different to that of single phase La _0.35 Sr _0.6 MnO ₃ . The interface has an important effect on the electric properties of the mixed ceramic and produces a dielectric relaxation in low frequency.