Water Disinfection Using Metal Doped Titania Nanoparticles

Abstract

The thesis presents the results of a study that examined the effectiveness of silver-doped titanium dioxide (TiO2) or titania nanoparticles. The nanoparticles synthesized by liquid impregnation method and were characterized using X-Ray Difrraction (XRD), Scanning Electron Microscopy (SEM) and Energy Disperssive Spectroscopy (EDS). The size of the nanoparticles were found to be ranged from 11 to 42 nm well below the cut-off range (100 nm) that defines such particles. 1% Ag-TiO2 was found to be very effective photocatalytic agent against gram –ve (E. coli) and gram +ve (S. aureus) bacterial groups. As expected, the death rate and extent, of these organisms, by photocatalysis under UV-A light was the maximum; more interestingly, however, was the observation that the silver-doped titania is also very effective in killing both type of bacteria under light in the visible spectrum from an ordinary fluroscent tube. Results with nanoparticles immobilized on a glass surface indicate that the development of self-sterilizing surface for commercial use is a distinct possibility.