摘要：为了研究双微乳液法在制备纳米级光催化剂的应用,以TiCl₄和NH₃.H₂O为原料,采用十六烷基三甲基溴化铵-正丁醇-环己烷-水微乳体系制备Fe³⁺掺杂纳米TiO₂,对粉末的晶体结构进行X射线衍射表征,并以其对p-甲酚的降解考察其光催化活性。结果表明,在较小的掺杂量时,Fe³⁺掺杂量的提高可以提高TiO₂的光催化活性,进一步提高掺杂量将引起光催化活性的降低;掺杂Fe³⁺可导致纳米TiO₂的粒径减小;Fe³⁺的半径较小以及Fe₂O₃的熔点较低均有利于TiO₂从锐钛矿向金红石的相变;当Fe³⁺掺杂摩尔分数为0.06%,煅烧温度为550℃时,纳米TiO₂的光催化活性最高,此时形成TiO₂的锐钛矿和金红石相的混晶;乳液中含水量也会影响晶相的组成和粒径大小,随着含水量增加产物中出现了一定比例的金红石相。

关键词：双微乳液；掺杂；纳米粉体；光催化

Abstract：In order to research the application of double microemulsion method for preparing nano-sized catalysts,Fe³⁺ doped TiO₂ nano-particles were obtained in microemulsion of CTAB-butanol-cyclohexane-H₂O with TiCl₄ and NH3·H2O as raw meterials.The crystal structure of Fe3+ doped TiO₂ nano-particles was characterized by XRD and the degradation of p-cresol was investigated for the photocatalytic activity of them.The results show that the photocatalytic activity increases with the increasing doping content of Fe³⁺ in a certain range and decreases with further increasing of doping content.The doped Fe³⁺ ions lead to decrease the particle size of TiO₂ nano-particles.The small radius of Fe³⁺ and low melting point of Fe₂O₃ can promote the phase transitions of anatase to rutile.When the doping molar fraction of Fe³⁺ is 0.06%,Fe³⁺ doped TiO₂ nano-particles calcined at 550 ℃ show the highest photocatalytic activity and emerge the mixed crystal of anatase and rutile.

Keywords：double microemulsion；doping；nano-particles；photocatalytic