Structure and dielectric studies of nano-composite Fe2O3: BaTiO3 prepared by sol–gel method

Nano-structure pure barium titanate (BaTiO3) and that was doped with iron oxide (Fe2O3), have been prepared by sol–gel method, using barium acetate (Ba(Ac)2) and titanium butoxide (Ti(C4H9O)4), as precursors. The as-grown prepared samples by sol–gel technique were found to be amorphous, which crystallized to the tetragonal phase after synthesized at 750 °C in air for 1 h as detected from the XRD patterns. The XRD data were confirmed by transmission electron microscope (TEM). The dielectric properties namely; dielectric constant (ε′) and loss tangent (tan δ) in the frequency range between 42 Hz and 1 MHz, at range of temperature 25–250 °C were investigated. The temperature dependence of ε′ and tan δ for the undoped and doped materials, at 1 kHz, was also investigated. As a result, tan δ increased rapidly with decreasing temperature below 125 °C (Curie temperature) while above this temperature, tan δ shows temperature independent. As a result, below and above Curie temperature, ferroelectric phase and paraelectric phase of BaTiO3 can be obtained, respectively.