Characterization of Ti-doped CaFe2O4 prepared from a malic acid complex

Ti-doped and undoped CaFe2O4 powders were prepared from a malic acid complex and their properties were evaluated using analytical instruments. According to an XRD measurement, there were no traces of impurity phases in 5 mol % Ti-doped CaFe2O4 powder, while impurity phases such as α-Fe2O3 and CaTiO3 were observed for 10 mol % Ti-doped CaFe2O4. When Ti was added to CaFe2O4, the crystallite growth of CaFe2O4 was suppressed and the BET surface area increased. SEM observation revealed that the addition of Ti atoms to CaFe2O4 causes interconnected CaFe2O4 particles to separate. From the results of an XRF measurement, it is suggested that Fe atoms are substituted with Ti atoms. The optical band gap of CaFe2O4 hardly changed as a result of doping with Ti.