溶胶-凝胶法制备纳米TiO_2/云母及光催化性能研究

Preparation of nano TiO_2/mica by sol-gel method and its photocatalytic properties

文章以钛酸四丁酯为钛源,采用溶胶-凝胶法制备了云母负载纳米TiO2光催化剂(TiO2/M),通过XRD、SEM、UV等手段对所制备的催化剂进行表征,并以甲基橙为模拟污染物检测其光催化活性;讨论了催化剂焙烧温度、光催化剂添加量及重复次数对光降解甲基橙活性的影响。结果表明,在焙烧温度为400～700℃时,纳米TiO2物相为锐钛矿相和金红石相混晶,随着焙烧温度的增加,锐钛矿相含量由90.9%逐渐降低为26.0%。经400℃焙烧2h制备的光催化剂的光催化活性达到最佳,在300W汞灯照射180min后,甲基橙降解率达到72%;相同条件下重复利用3次,180min对甲基橙的降解率仍可达60%。

Using tetrabutyl titanate as the source of titanium, nano TiO2/mica photocatalyst（TiO2/M） were prepared by the sol-gel method. The as-prepared materials were characterized by XRD, SEM, and UV methods. The methyl orange was used as simulated contamination to test the photocatalytic activity of the materials. The influence of calcination temperature, adding amount and repetition times on the photodegradation activity of methyl orange was also discussed. The results showed that the phases of as-prepared materials were mixed crystalline of anatase and rutile after the calcination from 400 ℃ to 700 ℃. With the increase of calcination temperature, the anatase content of TiO2 reduced from 90. 9% to 26.0%. After the calcination at 400 ℃ for 2 h, the photocatalyst achieved the best photocatalytic activity, the degradation rate of methyl orange reached 72 % after the radiation under 300 W mercury lamp for 180 mira the degradation rate of methyl orange was still up to 60% when this process was repeated three times under the same conditions.