Synthesis and structural characterization of three different tantalum-based ceramics

In this work, I have studied three different tantalum-based compositions: Ba(Y1/2Ta1/2)O-3, Ba(Mg1/3Ta2/3)O-3 and Ba(Zn1/3Ta2/3)O-3. The ceramic bodies were obtained by the solid-state reaction method or via a modified Pechini method. The Pechini powders, as well as the final ceramics were compositional, structural and morphological characterized by thermal analysis, X-ray diffraction, transmission electron microscopy and scanning electron microscopy. Single-phase powders with cubic structure, containing spherical nanosized particles, with average diameters between 13 and 25 nm, were obtained by modified Pechini method. In the case of Ba(Mg1/3Ta2/3)O-3, the sintering process makes possible the transition from a disordered cubic perovskite structure to a 1:2 ordered trigonal structure, specific to this type of ceramics. The ceramics synthesized via modified Pechini method exhibit intensive grain growth, resulting in higher grains sizes relatively to the conventional ceramics.