Influence of Processing Conditions on Crystal Structure of Bi6Fe2Ti3O18 Ceramics

Aim of the present research was to apply a solid state reaction route to fabricate Aurivillius-type ceramics described with the formula Bi₆Fe₂Ti₃O₁₈ (BFTO) and reveal the influence of processing conditions on its crystal structure. Pressureless sintering in ambient air was employed and the sintering temperatures were 850 and 1080 °C. It was found that the fabricated BFTO ceramics were multiphase ones. They consisted of two Bi_m+1Fe_m-3Ti₃O_3m+3 phases, namely the phase with m=5 (i.e. the stoichiometric phase) and m=4 (i.e. the phase with a reduced number of layers in the slab). Detailed X-ray diffraction patterns analysis showed that both phases adopted the same orthorhombic structure described with Fmm2 (42) space group. The ratio of weight fractions of the constituent phases (m=5): (m=4) was ~30:70.