MODIFICATION OF WIDE BANDGAP NANOMATERIALS FOR HETEROGENEOUS PHOTOCATALYSIS

Abstract

This work aims to modify wide bandgap nanomaterials such as TiO2 and SnO2 for applications in visible light photocatalysis via doping and nanocomposite formation. A simple synthesis methodology was adopted to allow convenient anion doping and nanocomposite formation to occur in one pot. The method was first established for TiO2 system and then applied successfully to SnO2 and ZnS systems. We found that the precursor thiourea can be used to provide nitrogen doping as well as inducing the formation of sulfides for coupling purposes. Thiourea was also found to react differently in the presence of the respective metal precursors. The changes in optical and physical properties were characterized via several techniques such as TEM, XPS, UV-visible spectroscopy and FT-IR spectroscopy. The resultant photoactivity of the as-synthesized materials was evaluated by monitoring the degradation of methylene blue dye under visible light irradiation and positive improvements were observed for all systems when compared to the host material.