纳米TiO2光催化剂的活性与使用寿命

Titanium dioxide nano-particles (for example， P₂₅， Germany， Degussa) have been internationally used as an effective photo-catalyst for many years. In this paper， characterization of P₂₅， photo-degradation ability as well as its life time has been systematically studied by employing methyl orange as a model pollutant. Many factors such as the pH value， pre-treatment have been investigated. Just like other nanometer-sized or ordinary Anatase TiO₂， the catalyst performs better at an optimal pH value. Pre-treatment of the catalyst also enhances the photo-catalytic a-bility. And the P₂₅ have shown rather good life time. The degradation products have been characterized by UV， mass and Raman spectrum. It is found that although the P₂₅ photo-catalyst has shown excellent decolourization a-bility， it is still difficult to degrade the methyl orange into small molecule， such as CO₂ and H₂O. Low-power ul-traviolet lamps (9W， 254nm) have been used throughout. A comparison experiment has been carried out under natural sunlight， and the results have shown that natural sunlight (With temperature below 10℃) could provide even more energy than that of the adopted ultraviolet lamp， which have proved P₂₅ a rather promising photo-catalyst for practical application in environment field under natural surrounding. The obtained results may serve as a valuable reference for the evaluation and preparation of high quality TiO₂ photo-catalyst.

Photo-Catalytic Activity and Life Time of the TiO2 Nano-Particles