Visible active novel semiconductor composites synthesis characterization and photocatalytic degradation of organic pollutants

Abstract

Rapid growth of industrialization and man-made activities led to air, water and land pollution. Currently, with the availability of limited resources of water, water pollution is one of the major environmental issues. The various carcinogenic pollutants such as dyes, pharmaceuticals waste, agrochemicals and industrial chemicals made water unfit for consumption. There are many physical, biological and chemical methods such as adsorption, chlorination, ozonation, AOP etc. Among them, the Advance Oxidation Processes (AOPs) are considered to be one of the most effective treatment methods in the degradation of variety of organic pollutants such as dyes, antibiotics, agrochemicals and industrial chemicals. In AOPs, production of superoxide radicals (and#9679;O2-) and hydroxyl radicals (OHand#9679;) play important role as they have the capability of attacking a wide variety of organic molecules. Among the different AOPs, photocatalysis using semiconductor oxides has attracted the attention of researchers over the past decades. Among different semiconductors, titania based semiconductors are widely used as photocatalyst due to their low cost, availability, non-toxicity and chemical stability. However, the large band gap (3.2 eV) and requirement of ultraviolet light (UV) for activating the TiO2 is extensively limiting the technology in practical photocatalytic applications. Only less than 4% of UV rays is present in the entire solar spectrum which hinders practical applications using solar irradiation newline