Obtenção e caracterização de filmes de TiO2 depositados sobre cerâmica de revestimento via magnetron sputtering DC
Titanium oxide (TiO2) under ultraviolet light becomes catalyst of chemical reactions. This phenomenon can be used to break down hydrocarbon and water molecules bound. Hydrocarbon was changing into water and carbon dioxide. Adsorbed water molecule is degraded by film and form a layer of adsorbed hydroxyl groups (OH), which are able to increase surface energy, becoming in superhydrophilic. Therefore, a continuous water film is formed and removes inorganic dirt. These phenomenons together can eliminate organic and inorganic substances from the surface and keep it clean for a long time, this is known as autocleanness. In this work, TiO2 thin films were deposited in aim of modify the surface behavior to create autocleanness ceramic. Such films are obtained by Direct Current Magnetron Sputtering, this process can develop high quality films, because it has high control and microstructure reproducibility. Thickness, composition and morphology were investigated, and tests are made to determine ceramic tiles photocatalyze efficiency, action hydrophilic and autocleanness. Nanometrics films (thickness from 120 to 890 nm) have an amorphous bulk, rich in rutile and anatase nanocrystals. Maximum anatase relative fractions of 80 %. When deposited on glass, it presents great transmittance, almost reaching float glass transmittance values. Films deposited on ceramic tiles and glasses presented good scratch hardness. Same samples degraded methylene blue in a few hours, showing the efficiency photocatalyze. Others reached contact angle at 30 , proving that some films are hydrophilic. Autocleanness tests determined the efficiency of deposited films; samples after a time were almost clean, similar behavior of commercial ones. The results show that the ceramic tiles deposited with titania films present photocatalytic, hydrophilics and autocleanness average properties similar to the commercials glasses.
Advisor:Orestes Estevam Alarcon; José Octávio Armani Paschoal; Márcio Celso Fredel; Paulo Cesar Borges; Sérgio Artur Bianchini Bilac; Luis César Fontana; Carlos Antônio Queiroz
School:Universidade Federal de Santa Catarina
Source Type:Master's Thesis
Date of Publication:10/22/2007