Phase transition in Sr modified Pb(SnTi)O3 system

The effect of Sr substitution on the structural and ferroelectric properties of Pb(SnTi)O3 system has been studied. The nanosized ceramic powders were synthesized by precursor solution method. Relative density >85% was obtained after sintering by covering it with lead zirconate powders in order to prevent lead loss. XRD shows that single-phase compound has been formed at 550 °C. The crystallite size varied from 55 to 80 nm. The increase in concentration of Sr content has lead to the increase in lattice parameters due to the reason that the ionic radius of Sr is more than that of substituting ion Pb. The structure of the phase formed is the same irrespective of the concentration of Sr. Detailed studies of the dielectric properties of the compounds show non-relaxor type ferroelectric transition. The diffusivity (γ) ranged from 1 to 1.2 revealing diffuse phase transition.