Heterogeneous and Homogeneous Photocatalysis for the Redox Conversion of Aquatic Pollutants
Solar energy utilization through heterogeneous and homogeneous photocatalysis has been intensively investigated for the redox conversion of aquatic pollutants. Heterogeneous photocatalysis using semiconductor oxide nanoparticles is a useful device for this purpose since the reactive oxygen species such as hydroxyl radicals and superoxides can be generated on the illuminated catalyst surface under the ambient condition. In particular, TiO2 is the most important base material for environmental photocatalysis and its photocatalytic activity has been demonstrated for a wide variety of organic and inorganic pollutants. The photocatalytic reaction rate and mechanism of pollutants degradation can be controlled by modifying the oxide nanoparticles. Various modification methods such as platinization, fluorination, dye sensitization, and surface complexation are introduced and their effects on the photocatalytic reactions are discussed. On the other hand, polyoxometallate (POM: metal-oxygen cluster anion) can be also utilized as a homogeneous photocatalyst that oxidizes organic compounds like TiO2. POM can be utilized as an electron-transfer mediating catalyst in many redox processes as well. Several examples of POM applications in environmental systems are introduced. The photocatalytic oxidation and reduction reactions carried out by POM are described and compared with those of TiO2 to discuss the similarities and differences. Finally, the iodide-mediated photocatalytic conversion of arsenite is described.
CHOI Wonyong
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Korea 790-784
国际会议
2011 International Symposium on Environmental Science and Technology(2011 环境科学与技术国际会议 2011 ISEST)
广东东莞
英文
497-504
2011-06-01（万方平台首次上网日期，不代表论文的发表时间）