Rare earth metal doped titania nanotubes for photocatalytic degradation of dyes

Abstract

Industrial pollution is the major source of global air, water and soil pollution and refers to all pollution which can directly or indirectly, be linked with industry. Due to the extensive use of organic dyes in industries, it has become an integral part of industrial effluent. The potential toxicity of dyes and their visibility in surface water, removal or degradation of organic dyes has been a matter of considerable interest. Conventional purification methods for effluent treatment include carbon adsorption, ozonation, microbial action and hydrolysis, but many of them are inefficient. Among the many processes proposed, semiconductor assisted photocatalysis has been widely employed to treat the effluent. TiO2 based photocatalyst have been extensively used in AOP, water splitting, and conversion of solar energy into electrical energy due to its excellent oxidation properties, low toxicity, strong photon stability and low cost. However, TiO2 is not sufficient for utilization of the abundant solar energy for the advanced oxidation process due to its wide band gap. Hence, tremendous researchers have been focused in developing titania with improved characteristics. TiO2 with nanotube morphology found to have significant interest because of its large surface area, large band gap energy. Under this event attempts are made to synthesis TiO2 nanotube by many methods including anodic oxidation, chemical vapour deposition and wet chemical method (hydrothermal and the sol gel). Among the methods employed, hydrothermal method has been a simple cost-effective and energy economical for scale up. Titania nanotube for instance, is one of the most popular and promising materials in heterogeneous photocatalytic application under UV irradiation. Diverse approaches are being made in search of a visible light active TNT photocatalysts. The present investigation has been focused on the modification of TNT by metal ions, to extend the light responsible range of TNT from the UV region to the visible region and further the visible light responsible range was enhanced by the formation of TNT with the addition of rare earth metals. newline