Broadband Impedance, Dielectric And Modulus Study of Ti-Doped LiSn2(PO4)3.

Abstract

LiSn2(PO4)3of composition LiSn1.85Ti0.15(PO4)3 with NASICON structure was prepared by solid-state synthesis. XRD results show the formation of stable phase material of rhombohedral structure with the R3 ̅c space group. Traces of SnO2 unreacted phase and minor impurities of SnP2O7 were detected. Impedance and dielectric study in the microwave range show conductivity enhancement in bulk and grain boundary. The room temperature ionic conductivity is 4.74x10-5 S/cm while the conductivity at 740 K is 2.37x10-3 S/cm. The highest value of dielectric constant ε' obtained is 2000 while the lowest value is 500. Imaginary modulus plot vs temperature indicates the presence of temperature relaxation in the material. The activation energy was calculated from plot of relaxation frequency at different temperatures and found to be 0.23 eV.