Nadir Kiraz

Photocatalytic antibacterial performance of Sn4+-doped TiO2 thin films on glass substrate.

Pure anatase, nanosized and Sn(4+) ion doped titanium dioxide (TiO(2)) particulates (TiO(2)-Sn(4+)) were synthesized by hydrothermal process. TiO(2)-Sn(4+) was used to coat glass surfaces to investigate the photocatalytic antibacterial effect of Sn(4+) doping to TiO(2) against gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus). Relationship between solid ratio of TiO(2)-Sn(4+) in coatings and antibacterial activity was reported. The particulates and the films were characterized using particle size analyzer, zeta potential analyzer, Brunauer-Emmett-Teller (BET), X-ray diffractometer (XRD), SEM, AAS and UV/VIS/NIR techniques. The results showed that TiO(2)-Sn(4+) is fully anatase crystalline form and easily dispersed in water. Increasing the solid ratio of TiO(2)-Sn(4+) from 10 to 50% in the coating solution increased antibacterial effect.

Sol-gel thin films with anti-reflective and self-cleaning properties

Self-cleaning photocatalytic TiO2 films are beneficial since they reduce the maintenance cost and enhance the efficiency of various optical systems, especially thermal and photovoltaic solar systems. However, the presence of a TiO2 layer on glass reduces the transmission of incident light, which leads to a decrease in efficiency. This drawback can be overcome by applying a layer of anti-reflective coating beneath the TiO2 layer. Generally, the anti-reflective layer is porous silica. The presence of the anti-reflective layer compensates for the loss of light transmittance caused by the photocatalytic TiO2 top layer. This paper reviews some of the previous and the latest fundamental studies in the literature on anti-reflective, self-cleaning and multi-functional films.