Microstructure and Electric Properties of (Sr 1− x Ca x ) 3 Sn 2 O 7 Ceramics with Ruddlesden-Popper Structure
(Sr1−xCa x )3Sn2O7 (x = 0, 0.1 and 0.2) ceramics were prepared by conventional solid solution method. The microstructure, dielectric and ferroelectric properties of (Sr1−xCa x )3Sn2O7 ceramics have been investigated systematically. The XRD results show that (Sr1−xCa x )3Sn2O7 ceramics is orthorhombic structure and the lattice constants decrease as Ca2+ content increases. The grain size of (Sr1−xCa x )3Sn2O7 ceramics decreases with the increasing of Ca2+ content, which results in the decrease of dielectric constant and dielectric loss. The compactness of (Sr1−xCa x )3Sn2O7 ceramics deteriorates as Ca2+ content increases, which causes the increase of leakage current density. Moreover, the introduction of Ca2+ in (Sr1−xCa x )3Sn2O7 ceramics leads to the increase of the remnant polarization. But the remnant polarization changes a little with Ca2+ content when x is above 0.1. The coercive field increases with the increasing of Ca2+ content.