Effect of microwaves on the synthesis, structural and dielectric properties of Ca-modified BaTiO3 ceramics

A pre-heat treatment with a domestic microwave, (MW), performed on gel-dry of sol gel processed Ca-modified BaTiO3, with the chemical formulation Ba1−x Ca x TiO3 such as x = 0, 1, 5, 10, 15, 20 and 30%, has been shown to lower the calcination temperature of these samples and to strongly influence their physicochemical properties. Indeed, X-ray diffraction and Raman characterizations of the samples revealed a gradual change from tetragonal to pseudo cubic phase with increasing x and a predominance of the occupation of the Ti-site for the composition x 10 (predominance of occupation of Ba-sites). The thermal behavior of the permittivity has been approached by the modified Uchino’s law, allowing the calculation of the dielectric parameters (diffuseness and relaxation parameters).