Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

PP-III-44MODELING AND OPTIMIZATION OF NOVEL PHOTOCATALYTICSYSTEMS BASED ON NANOSTRUCTURED TITANIAE.V. Skorb, D.G. Shchukin, D.V. SviridovInstitute for Physico-Chemical Problems of Belarusian State University,Leningradskaya Str 14, 220030, Minsk, Belarustel.: +375296384939, fax: +375172264696, e-mail: anok-skv@mail.ruModeling and optimization of novel photocatalytic systems based on nanostructuredtitania has been proposed and investigated. Particularly, photocatalytical coatings consistingof titania-based nanocontainers incorporated in the hybrid SiO x :ZrO x film were modeling andoptimized. The embedded nanocontainers demonstrate an ability of efficient light-drivenrelease of the loaded materials and at this basis novel multifunctional «smart» lightcontrollablecoatings with extra high bactericidal activity are developed.The incorporation of nanodispersed titania particles into the hybrid SiO x :ZrO x -based filmspermits to immobilize the different catalysts and obtain photacatalytically-active coatings atlow temperatures. The resultant thin-film photocatalysts reveal high activity towardsphotodestruction of organics both in aqueous solutions and in air conditions. The enhancedhydrophilicity inherent to the titania-loaded hybrid sol-gel films makes them a promisingmaterial for air purification and for self-cleaning coatings. These films also show high affinityto microorganisms and demonstrate enhanced photoinduced pathophysiological activitytowards both gram-negative and gram-positive bacteria. Of principle meaning is also the factthat the hybrid SiO x :ZrO x -based films used as the photocatalyst carrier are highly adhesiveand, being deposited onto the metal surface, behave as the anticorrosion coatings. Theproposed approach permits one to change radically the whole scheme of assembling thephotocatalytically-active coatings since the titania particles to be embedded into the hybridsol-gel film can be synthesized, annealed and then modified (if needed) separately. Moreover,the dispersions of different photocatalysts can be embedded in the SiO x :ZrO x matrix yieldingphotocatalytically-active coatings with mosaic surface that opens strong possibilities ofcontrolling the adsorption of chemical and bacterial contaminants.By applying polyelectrolyte shell over the particles of mesoporous titania via layer-bylayerassembly of oppositely charged polyelectrolytes it is possible to fabricate nano-scaledreservoirs which being immobilized by hybrid sol-gel film demonstrate an ability of lightdrivenrelease of the loaded materials. On this basis novel photocontrollable coatings whichcould be opened under UV or IR laser irradiation have been modeling and optimized.387