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.

摘要

在这项研究中，高温原位X射线衍射被用来研究铁掺杂二氧化钛（TiO ₂）的高温转变行为。结果表明，TiO ₂从锐钛矿（TiO ₂ -A）到金红石（TiO ₂ -R）的相变温度随着铁含量的增加而增加，并且铁的加入阻碍了二氧化钛从TiO ₂ -A 到金红石（TiO ₂ -R）的转变。TiO ₂ -R，其降低了TiO ₂相变温度区间。其机理如下：一方面，铁的掺入降低了 TiO ₂ -A 和 TiO ₂的晶粒尺寸。-R，晶粒细化提高了相变温度；另一方面，渗入TiO _{2 中}的Fe ³⁺吸引O 原子的电子云，使O 原子在高温相变过程中向Fe ³⁺移动，导致TiO _{2 中}的晶体缺陷加速TiO ₂ - A向TiO ₂ -R相变反应并降低相变温度范围。