Effect of platinum on the photocatalytic degradation of chlorinated organic compound

TiO2 nanoparticles, doped with di erent Pt contents, were prepared by a modified photodeposition method using Degussa P-25 TiO2, H2PtCl6 6H2O and methanol as the solvents. The physicochemical properties of Pt/TiO2 were investigated by the nitrogen adsorption and desorption isotherm measurement technique, X-ray di raction analysis and photoluminescence spectra, respectively. Reaction rates from photocatalytic removal of dichloromethane over Degussa P-25 TiO2 and Pt/TiO2 were evaluated. The average diameter and BET surface area of the TiO2 catalyst particles were 300 nm and 50 m2/g, respectively. The degradation e ciency was 99.0%, 82.7%, 55.2%, and 57.9% with TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. And the degradation e ciency was 99.3%, 79.7%, 76.5%, and 73.4% with a 0.005 wt.% Pt/TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. In addition, we found that the photoluminescence emission peak intensities decreased with increases in the doping amount of Pt, which indicates that the irradiative recombination was weakened. Furthermore, the results showed that the UV/0.005 wt.% Pt/TiO2 process was capable of e ciently decomposing gaseous DCM in air.     

热释光与光致发光技术测定累积剂量的比较

国内测定累积剂量的方法多为热释光技术，但其易受环境因素的影响。光致发光作为一种新技术，具有良好的环境稳定性，能量响应范围较宽。因此，对热释光与光致发光技术测定累积剂量，从原理、方法、性能方面进行了比较，讨论了两者各自的特点及应用。     

光致发光材料的安全问题探讨

本文对光致发光材料的安全问题进行了初步探讨，硫化物型的发光材料性能不稳定，在生产和使用中应注意安全的防护，新型稀土发光的材料性能稳定，余辉时间长，亮度高，对人安全无毒。     

光纤ZnO薄膜的制备及光催化性能研究

实验利用射频磁控溅射镀膜工艺，分别在光纤和石英玻璃上成功制备了ZnO薄膜。采用X射线衍射仪、原子力显微镜和荧光分光光度计对薄膜进行了测试分析，并对其光催化降解苯酚的性能进行了对比测试。结果表明，该薄膜具有良好的C轴取向性，光致发光峰分别位于362nm、421nm和486nm附近，且随着薄膜样品晶粒的减小而出现蓝移，光纤上ZnO薄膜的光催化能力是以石英玻璃为基底的ZnO薄膜的1．93倍，光催化效果显著。