Photocatalytic decomposition on nano-TiO2: Destruction of chloroaromatic compounds

Photocatalysis is applied increasingly in addressing and solving environmental and energy-related problems. Especially the TiO2-derived catalysts attract attention because of their catalytic efficiency, wide range of applications, ease in use, and low cost (it costs about 150 Yuan a kilogram in China). This review first describes the principles of photocatalytic destruction by semiconductors and then focuses on degradation rates and reaction mechanisms in a variety of photocatalytic uses of modified TiO2. Finally, these concepts are illustrated by selected examples relating to the photocatalytic degradation of organic persistent pollutants, such as polychlorinated benzenes (PCBz), biphenyls (PCB) and dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). And some approaches towards industrial application are analyzed.

Research highlights
► The principles of photocatalytic destruction by semiconductors are described.
► Degradation rates and reaction mechanisms of modified TiO2 are illustrated.
► Destructions of many kinds of chloroaromatic compounds using TiO2 are classified.
► Some approaches towards industrial application are analysed.