Phase transition behavior of Sc-substituted Pb(Yb1/2N1/2)O-3 ceramics

Abstract

The crystal structure and the dielectric properties of (1-x)Pb(Yb1/2Nb1/2)O-3-xPb(Sc1/2Nb1/2)O-3 (PYN1-xPSNx) (0 less than or equal to x less than or equal to 0.50) solid solution have been studied. According to the XRD study, the room temperature crystal structure of PYN1-xPSNx becomes pseudocubic from the PYN's orthothombic with increasing x . Also the diffraction line intensities ascribed respectively to the AFE lattice modulation and the B-site ordering become gradually weaker and they disappear altogether for x > 0.30. In the PYN-rich composition range (0 less than or equal to x less than or equal to 0.30), the paraelectric(PE)-antiferroelectric(AFE) phase transition occurs sharply and is independent of the applied frequency. However, on further increasing Sc concentration (0.30 < x less than or equal to 0.50), the dielectric constant vs. temperature curve becomes gradually broader and begins to display the frequency-dependent relaxor behavior.