College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
J Hazard Mater. 2010 Jun 15;178(1-3):152-6. doi: 10.1016/j.jhazmat.2010.01.056. Epub 2010 Jan 18.
A novel photodegradable polyvinyl chloride (PVC)-vitamin C (VC)-TiO(2) nano-composite film was prepared by embedding VC modified nano-TiO(2) photocatalyst into the commercial PVC plastic. The solid-phase photocatalytic degradation behavior of PVC-VC-TiO(2) nano-composite film under UV light irradiation was investigated and compared with those of the PVC-TiO(2) film and the pure PVC film, with the aid of UV-Vis spectroscopy, scanning electron microscopy (SEM), weight loss monitoring, and X-ray diffraction spectra (XRD). The results show that PVC-VC-TiO(2) nano-composite film has a high photocatalytic activity; the photocatalytic degradation rate of it is two times higher than that of PVC-TiO(2) film and fifteen times higher than that of pure PVC film. The optimal mass ratio of VC to TiO(2) is found to be 0.5. The mechanism of enhancing photocatalytic activity is attributed to the formation of a Ti(IV)-VC charge-transfer complex with five-member chelate ring structure and a rapid photogenerated charge separation is thus achieved.
一种新型的可光降解聚氯乙烯（PVC）-维生素 C（VC）-TiO2纳米复合材料膜是通过将 VC 改性纳米 TiO2光催化剂嵌入商业 PVC 塑料中制备的。在紫外光照射下，研究了 PVC-VC-TiO2纳米复合材料膜的固相光催化降解行为，并与 PVC-TiO2膜和纯 PVC 膜进行了比较，借助于紫外-可见光谱、扫描电子显微镜（SEM）、失重监测和 X 射线衍射谱（XRD）。结果表明，PVC-VC-TiO2纳米复合材料膜具有高的光催化活性；其光催化降解速率是 PVC-TiO2膜的两倍，是纯 PVC 膜的十五倍。发现 VC 与 TiO2的最佳质量比为 0.5。增强光催化活性的机制归因于形成具有五元螯合环结构的 Ti（IV）-VC 电荷转移配合物，从而实现快速光生电荷分离。
