Sonophotocatalytic degradation of organic pollutants using nanomaterials #18

Abstract

The textile, cosmetic, and food industries use different organic compounds that are more toxic and non-biodegradable. These compounds are the most important source of water contamination, and hence the treatment of these wastewaters is important to protect the ecosystem. Sonophotocatalytic degradation is an effective method used for the removal of organic pollutant from wastewater. Sonophotocatalysis has received increased attention in advanced oxidation processes for the degradation of organic pollutants, which involves the combination of ultrasound waves and semiconductor photocatalyst to enhance the degradation rate. Different types of semiconductor photocatalysts are used in sonophotocatalysis; among these, the most widely used photocatalysts are TiO2 and ZnO. The degradation efficiency is low when sonolysis or photocatalysis is used alone. In order to increase the degradation efficiency, researchers focused on developing new materials by doping of metal ions or use of composite semiconductor materials. This chapter deals with a detailed analysis of research reports published so far on the nano-sized materials such as TiO2, ZnO, metal sulfides, and composite materials used in sonophotocatalysis. The reaction mechanism of the sonophotocatalysis for the degradation of organic pollutants is also discussed in detail.