Structural and magnetic characterization of Ti-substituted Li0.5Fe2.5O4 prepared using hydrothermal and solid-state routes

Single-phased spinel-related Ti4+-substituted Li0.5Fe2.5O4 has been synthesized by heating a mixture of hydrothermally prepared Ti4+-substituted α-Fe2O3 and Li2CO3 at 8500C (12 h). This temperature is ca. 250-3500C lower than those at which the material is conventionally prepared by the ceramic techniques. X-ray diffraction was used to analyze the evolution of the formation process and, in conjunction with Moessbauer and magnetization measurements, to determine the cation distribution of the resulting ferrite. The results imply that the Ti4+ ions substitute for Fe3+ ones at the octahedral (B) sites whilst the excess Li+ ions, required for balancing the charge in the spinel-related structure, replace Fe3+ ions at the tetrahedral (A) sites.