La掺杂混晶TiO_2薄膜的制备及光催化活性

Preparation and photocatalysis activity of La-doped mixed crystal TiO_2 films

为提高TiO2的光催化降解性能,达到利用光能降解环境污染物的目的,对TiO2光催化剂进行了掺杂改性研究.通过在氟钛酸铵、硼酸混合溶液中加入硝酸镧,应用液相沉积法(LPD)制备了掺镧TiO2复合薄膜.采用XRD、UV-Vis、XPS、SEM等手段对TiO2薄膜的组成、结构和表面形貌进行了测试表征,并以甲基橙溶液的降解反应评价掺镧TiO2薄膜的光催化性能.实验结果表明:硼酸/氟钛酸铵摩尔比为2～4时,掺镧TiO2薄膜具有锐钛矿和金红石混晶型,热处理温度为400℃,硝酸镧掺杂量为0.01 mol/L时,具有较好的光催化性能.

In order to improve the photodegradation of TiO2 and reduce environmental pollutants by using light energy,TiO2 photocatalyst modified by doping was studied in this paper.La-doped TiO2 composite films were prepared by adding lanthanum nitrate into the mixed solution of ammonium fluotitanate and boric acid and by liquid phase deposition（LPD） method.The composition,structure,and surface form of titanium dioxide thin films were studied in XRD,UV-Vis,XPS,and SEM means,and the photocatalytic activity of the thin films was evaluated by the degradation of the methyl orange solution.The results show that when the mol ratio of boric acid and ammonium fluotitanate is 2~4,the La-doped TiO2 films are composed of anatase and rutile mixed crystal;when the heat treatment temperature is 400℃ and the mixed volume of lanthanum nitrate is 0.01 mol/L,the film has good photocatalytic activity.