Reaction mechanism for photocatalytic degradation of organic pollutants

Abstract

Abstract Photocatalysis includes the study of both photochemistry and catalysis. Photoinduced reactions in a heterogeneous photocatalysis system occur at the surface of the catalyst, within which the initial reaction being oxidation, generating positive holes due to photoinduction, and the following reaction is reduction because of photoexcited negative electrons. As such, this photocatalytic system is now of great interest as one of the most favorable ways to solve environment-related problems, such as air purification, water treatment, water disinfection, and harmful waste remediation. Continuing on the path to find better and sustainable materials, scientists are now focusing on semiconductor materials to be used as photocatalysts to eliminate various types of organic pollutants from wastewater. The use of such semiconductor materials is increasing to degrade or oxidize numerous organic dyes and many other harmful contaminants which are particularly found in industrial wastewater. The rudimentary mechanism of photocatalytic remediation is mainly based on the surface oxygen defects of semiconductor materials, which are activated by the irradiation of photons.