Structural, dielectric and piezoelectric properties of nanopowders of pure and strontium-doped BaTiO3 (Ba1-xSrx)TiO3 (x = 0.00; 0.10; 0.20; 0.30 and 0.40), synthesized by the sol gel process, have been investigated. The samples crystallize in the pure perovskite structure and transform from tetragonal to pseudocubic under doping with Sr. The calculated average crystallite size was about 30 nm. Dielectric parameters (dielectric permittivity and losses) were determined. Sr doping gives rise to a decrease of the ferro-to-paraelctric transition temperature and to an enhancement of the Positive Temperature Coefficient of Resistivity (PTCR). Piezoelectric parameters were also determined and their thermal behavior investigated.
Keywords: (Ba, Sr)TiO3 ceramics, Sol Gel, Dielectric properties, Complex impedance, PTCR and Piezoelectric properties.