尿素改性TiO2光催化剂性能研究

The photocatalytic properties of TiO_2 modified by urea

选择尿素对TiO2进行掺杂,再用蒙脱土进行负载,制备高催化活性的改性TiO2/蒙脱土(MMT)复合光催化剂。通过光降解亚甲基蓝试验,研究不同制备条件对光催化剂活性的影响。结果表明,当尿素与国产TiO2的掺杂比为1∶0.1时亚甲基蓝的降解效果最好,其光降解速率常数最高达0.251 13 h-1,降解率为56%;用蒙脱土对尿素改性后的P25(Degussa)进行负载,发现对亚甲基蓝的降解率比未进行负载的高十几个百分点,且蒙脱土与改性P25混合比为15∶1时降解速率最高,达0.226 13 h-1。

The TiO2 composite photocatalysts were synthesized by a simple method which doped with urea and loaded with MMT. The influences of different preparation condition on properties of modified TiO2/（ MMT） was investigated by measuring the degradation rate of methylene-blue（ MB） under the irradiation of fluorescent lamp. The results showed that the catalyst has the best photocatalytic activity for degradation MB with the mass ratio of urea ∶ TiO2= 1 ∶ 0. 1,the degradation efficiency up to 56%,and the apparent degradation rate constant of MB was 0. 251 13 h^- 1; the photocatalytic activity of the P25 modified by urea and with mass radio of MMT∶ modified P25 = 15∶ 1 is ten more percent higer than P25 only modified by urea under the same experimental condition,and the apparent degradation rate constant was up to 0. 226 13 h^- 1.