Nonmetals doped photocatalysts supported over graphene synthesis characterization and catalytic activity

Abstract

Energy and environmental issues are the biggest challenges of 21st newlinecentury. One of the most persistent problems affecting people throughout the newlineworld is inadequate access to clean water and sanitation. Water pollution has newlinebeen a very troublesome problem and the scarcity of water is expected to newlinegrow worse in the coming decades even in regions which are currently newlineconsidered as water rich areas. Various organic pollutants such as textile dyes, newlineleather dyes, pharmaceutical wastes from hospitals, animal husbandries and newlineagrochemicals such as pesticides, insecticides, fungicides, weedicides and newlinefertilizers are found in water streams and they make an adverse impact on newlinepublic health and social economy. Several treatment methods have been used newlinein the past for the treatment of waste water such as adsorption, coagulation, newlineflocculation, chlorination, ozonation, bio-degradation and photocatalytic newlinedegradation.Among the above methods, photocatalytic degradation seems to be newlinethe most convenient approach due to (i) its environment friendly nature newline(ii) complete mineralization (iii) no waste disposal problems and (iv) works newlinevery well at mild temperature and pressure. Moreover, the photocatalytic newlinedegradation is effective even at much lower concentrations of organic newlinepollutants. Therefore, photocatalytic degradation is a promising solution to newlinedegrade organic pollutants. Titania (TiO2) is widely used photo catalyst as it newlinepossesses excellent properties of nontoxicity, chemical inertness and no photo newlinecorrosion. However, the band gap of anatase phase of TiO2 is about 3.2 eV, newlinewhich allows to absorb only ultraviolet (UV) light. When solar radiation is newlineused only 4% of it can be used for photocatalytic reaction and hence TiO2. newline newline