Nanostructured films: on the influence of the architecture on Photoactivity properties of films with phosphotungstate and nanoparticles

Abstract

This porposal aims to understand the relationship between chemical composition-strucutre-morphology and photochemical reactivity of nanostrucutred thin films. The photoactive compounds studied are semiconducting oxides (TiO2 and ZnO) and the polyoxometalate phosphotugstate. A second approach is intending to use shell@core TiO2@SiO2 nanoparticles as photoactive element, instead the TiO2 or ZnO. This approach allows us to tune the energy of the border level of the conduction band of the semiconductor by controlling the thickness of the TiO2 shell. Such control is intending to result on higher efficiency of Reactive Oxygen Species generation, such as hydroxyl radical, as well as result on higher photochromic activity. The photoactive compounds are going to be dispersed in two different solid matrix: Ormosils and Electrostactic Layer-by-Layer films. The multilayered films are going to be build by dip coating using poyphoshates are polyeelectrolytes. The photo-reactivity is going to be evaluatyced by recording the photochromic behavior and their photocatalytic activity for degradation of lipids and s-triazines. Their photocatalytic activity is going to be evaluated by studying their photochromic activity and their their photocatalytic activity toward N-Oxide-5,5-Dimethyl-1-Pirroline, methylene blue and violet crystal. These chemicals were chosen due to their recognized reactivity toward OH radicals generated by the photocatalytic species. Moreover, the ormosis photoreactivity is going to be essayed toward s-triazines, melamine and atrazina. New class II hybrid Materials with poly(dimethylsiloxane) and silicate interpenetrating network chemically bonded through urethane bond will be prepared aiming higher mechanical, chemical and photochemical stability as matrices to the photoactive materials, phosphotungstate and TiO2 and ZnO. (AU)