Bi_2O_3/TiO_2复合光催化剂对甲基橙的光催化作用

Photocatalytic Research of Bi_2O_3/TiO_2 Composite Catalysts on Methyl Orange

以溶胶-凝胶法制备了Bi2O3/TiO2复合光催化剂,用TEM、HRTEM、XRD、Raman、FTIR、PL、UV-Vis DRS等对其结构、性质进行表征,并以甲基橙为有机污染物对Bi2O3/TiO2复合光催化剂活性进行研究。结果表明:复合少量Bi2O3可抑制TiO2由锐钛矿相到金红石相相变及其颗粒的生长。n(Bi)∶n(Ti)=0.017 5配比的Bi2O3/TiO2复合光催化剂活性最好,当用量为2.5g/L时,25mg/L的甲基橙溶液在500 W氙灯下照射5h后,脱色率达到99.4%,2.1倍于Degussa P25TiO2。

Bi2O3/TiOz nanoparticles was prepared by sol-gel method, and the structure and surface properties of the as-prepared Bi2O3/TiO2 were characterized by means of TEM, HRTEM, XRD, Raman, FTIR, UV-Vis DRS, etc. Fur- thermore, their photoactivity was evaluated by degrading methyl orange_ The experimental results showed that compound with low amount of Bi2O3 could effectively inhibit the phase transformation from anatase to rutile and the crystal growth. The highest photocatalytic activity was gotten when the ratio of n（Bi） ： n（Ti） was 0. 017 5. When the concentration of catalyst loading was 2. 5 g/L, the decolorization rate of 25 mg/L methyl orange reached 99.4% , which was 2. 1 times higher than that of Degussa P25 TiO2 under the irradiation of the 500 W xenon lamp after 5 h.