Synthesis of the Aurivillius Phase SrBi4Ti4O15 by a Mechanochemical Activation Route

This work reports the results obtained on the synthesis of the Aurivillius oxide SrBi4Ti4O15 as carried out by mechanochemically assisted methods. The effects of changing the milling media (vibrating and planetary mills) and the length of the mechanical treatment are discussed. The products obtained were characterized by X-ray diffraction at room and high temperatures, thermal analysis, and scanning electron microscopy. When an amorphous mechanochemically activated precursor is annealed at low temperatures, a novel Sr-Bi-Ti-O fluorite-related phase is isolated. The bismuth layered perovskite can be obtained with a significant decrease in temperature (of about 500 °C) and reaction time (several days), as compared with the conventional ceramic synthesis method. The mechanically treated samples exhibit a homogeneous particle size of around 300 nm, which increases with further thermal annealing.