Abstract

Retardation of Photocatalytic Activity of ZnS on Coprecipitation with CoS : Bleaching of Rose Bengal

Author(s): Neelima Rajawat, Surbhi Benjamin, P.B. Punjabi and Suresh C. Ameta

Photocatalysis has been established as an emerging technology for waste water treatment, since photocatalytic activity of number of semiconducting materials has already been established. Sulphides of different transition metals have been used as photocatalysts. The photocatalytic degradation of rose bengal has been investigated using ZnS and coprecipitated ZnS-CoS. The photocatalytic degradation of dye was monitored spectrophotometrically. The effect of variation of different parameters like pH, concentration of dye, amount of semiconductor and light intensity on the rate of photobleaching was also observed. A retardation in the rate of reaction was observed in case of coprecipitated ZnS-CoS. A tentative mechanism for the photocatalytic degradation of rose bengal has also been proposed.