High-temperature transformation behavior of iron-doped titanium dioxide crystal structures

Abstract

ABSTRACT In this research, high-temperature in situ X-ray diffraction were used to study the high-temperature transformation behavior of the iron-doped titanium dioxide (TiO2). The results show that the phase transformation temperature of TiO2 from anatase (TiO2-A) to rutile (TiO2-R) increased with increasing iron content and that the addition of iron impeded the transformation of titanium dioxide from TiO2-A to TiO2-R, which decreased the TiO2 phase transformation temperature interval. The mechanism is as follows: on the one hand, the incorporation of iron decreases the grain size of both TiO2-A and TiO2-R, and refinement of the grains increases the phase transformation temperature; on the other hand, the Fe3+ infiltrated into TiO2 attracts electron cloud of O atoms,causing O atoms to move towards Fe3+ during the high-temperature phase transformation, causing the crystal defects in TiO2 to accelerate the TiO2-A to TiO2-R phase transformation reaction and decrease the phase transformation temperature range.