Синтеза-структура-својства-примена на TiO2 превлека како фотокатализатор во градежни материјали

Abstract

Protective self - cleaning coatings could reduce or eliminate degradation processes of building materials, especially when they are exposed on variable external conditions. The coatings enable the removal of the pollutants from the surface of materials. In this doctoral thesis the goal was to design coating with photocatalytic and self-clening properties which will be finally applied on mineral substrates. So, the research was focused on investigating four systems where nano (3 and 10 wt.%) TiO2 was impregnated on different mineral carriers (synthesized ZnAl layered double hydroxide, Zn-Al LDH, and three different types of natural clay). The impregnation of nano TiO2 on Zn-Al LDH carrier was accomplished by vacuum evaporation prior to the mechanical activation (planetary mill) and only by the mechanical activation (realized in atritor). The impregnation of nano TiO2 on natural clays was realized only by mechanical activation, but in two different mils: planetary mill and atritor. The obtained composite powders (ZnAl LDH-TiO2 and clays-TiO2) after impregnation were characterized from aspect of granulometric composition, mineralogical composition, photocatalytic activity and particle morphology. The composite powders that showed the greatest photocatalytic activity, which was in direct correlation with the way of impregnation, content of nano TiO2, particle size distribution and their crystallinity, were further used for the coatings preparation. The prepared coatings were applied on mineral substrates (with different porosity) and then examined from the aspect of photocatalytic activity, self-cleaning and their durability. The durability of photocatalytically active coatings was tested through modified rinsing and adhesion tests. The obtained coatings applied on different mineral substrates can be potentially used as self-cleaning and photocatalitical materials in building sector.