Solar Energy as a Tool for Waste Water Treatment

Abstract

Photocatalysis is a method which is used for treating of waste water in a greener way or less utilisation of energy or raw materials. It is relatively new area and the most promising method for the treatment of wastewater. The process utilises solar radiation to excite the semiconductor material which is called as photocatalyst in which the valence band and the conduction band are separated by a band gap. Due to solar radiation the band gap can be overcome by shifting of electrons from valence band to conduction band and thus help in oxidation of electrons which in waste water will finally leads to decolourisation of the effluent.

Keywords: Photocatalysis, effluent, excitation, semiconductor material