Studies on degradation of some organic pollutants using zinc based nanomaterials

Abstract

In order to achieve a stable economy, rapid advancement of industries has brought terrific newlinepressure on the water resources. The mainstream of water is getting polluted due to untreated newlinedischarge of industrial effluents. Organic pollutants are one of the most toxic contaminants found newlinein the polluted water. Various strategies have been employed in the removal process of organic newlinepollutants. However, the traditional removal methods have certain limitations associated along newlinewith them. Nanotechnology has emerged as a promising approach in the removal of various newlinewater contaminants. Nanomaterials have fascinating surface and catalytic properties benefitting newlinethe water treatment processes. Recently, the role of metal hexacyanoferrates has been explored in newlinethe degradation of pollutants. Metal hexacyanoferrate nanoparticles are highly surface active and newlinestable. Zinc oxide, titanium oxide and other metal oxides have been immensely utilized in the newlinewaste water treatment. But the limitation of higher band gap energy values restricts their use newlinewithin the ultra violet region of light. It has been found that the modification of basic materials newlinethrough their coupling, pairing or encapsulation with other materialscanenhance the surface newlineactivity and lower the band gap energy values. Moreover, the coupled materials have tendency of newlineoxidizing as well as degrading the pollutants through the support of various reactive species newline(superoxide or hydroxyl radical). Coupling introduced additional energy levels in newlinesemiconducting phenomena and enhanced the surface activity of the catalysts. The incorporation newlineof zinc in any form has helped in creating a biocompatible agent. In view of the above newlinediscussion, green synthesis of various zinc based metal hexacyanoferrates coupled nanomaterials newlinewas carried out using Azadirachta indica plant extract and water. The synthesized nanomaterials newlinewere applied for the photocatalytic degradation of various organic contaminants, namely, lower newlineand higher molecular weight polycyclic aromatic hydrocarb