铁离子掺杂TiO2 的制备及其光催化性能

将Bola型两亲性短肽KI₃E在水溶液中组装成稳定的纤维状结构，以其自组装体作为有机模板并使用氨丙基三乙氧基硅烷为结构导向剂，利用其对TiO₂前驱体-二(2-羟基丙酸)二氢氧化二铵合钛的水解催化作用以及肽模板与铁离子之间的分子识别作用在TiO₂矿化沉积的同时引入铁离子，在温和的水溶液中制备出铁离子掺杂TiO₂纳米材料。使用TEM、BET、UV-vis DRS、XPS、XRD等手段对其结构和性能进行了表征。结果表明，铁元素以Fe²⁺/Fe³⁺的形式存在于TiO₂晶格中，抑制了晶体生长并使晶粒尺寸变小。同时，铁离子的掺杂减小了TiO₂的禁带宽度，提高了对可见光的响应和催化性质。铁离子掺杂量为0.5% TiO₂，其光催化性能最好。

Preparation and Photocatalytic Property of Iron-doped Titanium Dioxide Nanomaterials

Iron-doped titanium dioxide (Fe-TiO₂) nanomaterials were prepared with the stable fibrous nanostructure of self-assembled bola-type amphiphilic short peptide KI₃E as organic templateand aminopropyl triethoxysilane as structure-directing agent via sol-gel process to ensure the simultaneous deposition of the titanium dioxide precursor and iron ions on the surface of the peptide templates. The Fe doped-TiO₂ nanomaterials were fully characterized by Transmission electron microscope, UV-vis diffuse reflection spectroscopy, X-ray photoelectron spectroscopy, X-ray diffractometer. The results show that iron ions instead of partial titanium ions in the crystal lattice of titanium dioxide, which narrows the band gap of TiO₂ and results in enhanced visible light responses. The test results of photocatalytic degradation of rhodamine B and methylene blue indicated that the Fe doped-TiO₂ possessed significantly enhanced photocatalytic performance, compared to the commercial TiO₂ (P25), while reached a maximum when the doping content of iron ions was 0.5%.