Electron microscopy, XRD, Mossbauer and dielectric studies of Pb(Fe0.5Nb0.5)(1-x)SnxO3 multiferroic ceramics

摘要

Multiferroic Pb(Fe0.5Nb0.5)(1-x)SnxO3 (x = 0.025, 0.05, 0.075, 0.10) ceramic compositions were prepared by solid state synthesis and usual sintering. XRD studies have shown a formation of the perovskite structure in all the compositions studied. However, a small amount of pyrochlore phase was detected in Sn-doped compositions with x0.05. Scanning electron microscopy studies have shown that at the boundaries of the large grains there exist a lot of small submicron grains enriched by Sn. Concentration dependencies of the unit-cell parameter and ferroelectric phase transition temperatures also imply that solubility of Sn in PFN is limited to approximate to 5 at.%.