A short literature survey on iron and cobalt ion doped TiO_2 thin films and photocatalytic activity of these films against fungi

摘要

In this study, a short recent literature survey which concentrated on the usage of Fe~(3+) or Co~(2+) ion doped TiO_2 thin films and suspensions were summarized. Additionally, a sol-gel method was used for preparation of the 2% Co or Fe doped TiO_2 thin films. The surface of the prepared materials was characterised using scanning-electron microscopy (SEM) combined with energy dispersive X-ray (EDX) analysis and band gap of the films were calculated from the transmission measurements that were taken over the range of 190 and 1100 nm. The E_g value was 3.40 eV for the pure TiO_2, 3.00 eV for the Fe-doped TiO_2 film and 3.25 eV for Co-TiO_2 thin film. Iron or cobalt doping at lower concentration produce more uniformed particles and doping greatly affected the size and shape of the TiO_2 nanoparticles. Photocatalytic killing effect of the 2% Co doped TiO_2 thin film on Candida albicans was significantly higher than Fe doped TiO_2 thin film for short and long exposure periods. Doped thin films were more effective on Aspergillus niger for short exposure periods.