Synthesis of Pseudobrookite Fe_2-xAl_xTiO₅(0 ≤ x ≤ 0.5) Powders

Synthesis of Fe2-xAlxTiO5 (0≤x≤0.5) powders has been successfully conducted by using the solid state reaction method. The powders were made by mixing the ironstone-derived Fe2O3 and commercial TiO2 powder. Meanwhile, a commercial Al (NO3)3.9H2O precursor was used as the source of Al. The Fe2O3, TiO2, and Al(NO3)3.9H2O powders at the designated composition were mixed and then ground for 5 hours at 330 rpm in a planetary ball mill. Subsequently, the powder mixtures were calcined at 1100 °C for 1 h. Synchrotron x-ray diffractometry (SXRD) and scanning electron microscopy (SEM) techniques were used to characterize the phases and microstructures. SXRD data showed that a single-phase pseudobrookite Fe2TiO5 formed for all samples. A further quantitative analysis showed that the lattice parameter and cell volume values decreased with the increase of x which indicated the success of Al doping in the Fe2TiO5 structure. The morphology of Fe2-xAlxTiO5 grains from SEM images revealed an oval and elongated shapes, in accordance with the crystal structure of the phase.