Determination of A.C. Conductivity of Nano-Composite

Nano-composite, perovskite Ba(1–x–y)Sr(x)TiFe(y)O3, denoted as (BSTF) in powder form was derived via sol-gel (SG) method followed by sintering at fixed temperature 750˚C for one hour. The morphology and structure of the powder samples were investigated by using X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM). The XRD characterization indicates formation of a tetragonal crystalline phase in the pure BST. A well defined perovskite phase with nano-crystallite sizes equal to about 32 nm was achieved from XRD for B10ST20F sample, while TEM study confirmed the obtained XRD results giving the following crystallite size value about 29.82 nm for the same sample. The dielectric A.C. conductivity was evaluated as a function of temperature and frequency ranging from 42 Hz up to 1 MHz.