Heterostructures based on semiconductor nanocrystals: synthesis and evaluation for photocatalysis of the organic contaminant degradation in water

Abstract

Water contamination by organic recalcitrant compounds as commercial dyes and pesticides is still demanding novel methods and materials for their degradation and consequently water reuse. Among the main materials for that, heterostructures composed by different semiconductor oxide nanoparticles have been studied due their high activity as photocatalysts. However, the mechanisms involved in their different photoactivities as well as the more adequate oxide combinations are not elucidated yet. Then, this project propose a detailed studied about the heterostructure formation of TiO2 (both anatase and rutile) with other semiconductors as SnO2, WO3, V2O5 and Nb2O5, obtained mainly by the oxidant peroxide method (OPM) under hydrothermal conditions for crystallization. Also, the photocatalytic properties of each system in diferent Ti:M ratios (M = Sn, W, V ou Nb) will be evaluated. OPM route will be applied since it is considerably simple and clean, avoiding interferences from additives in the final properties. Morphology, physical and chemical properties will be evaluated through conventional (X Ray Diffraction, Raman spectroscopy, Zeta potencial and surface area measurements, photoluminescence spectroscopy and scanning electron microscopy) and advanced techniques, such as high-resolution transmission electron microscopy and X Ray absorption spectroscopy. Photocatalytical efficiency will be evaluated in the degradation of different substrates under UV and Vis irradiation comparing the results through the different systems analyzed. (AU)