Applications of polystyrene/graphite composites in water purification as a semiconductor visible-light photocatalyst for organic pollutant degradation

Abstract

The aim of this study was to prepare a polymer/graphite composite thin film as a cheap, and nontoxic photocatalyst that could be activated by visible light. It was characterized using ultraviolet/visible spectrophotometry and X-ray diffraction. Scanning electron microscopy was used to examine the photocatalyst surface before and after a photodegradation process. The photocatalyst showed activity under visible light and was used for the photodegradation of methylene blue (MB) and rhodamine B (Rh-B) as target pollutants. The process was studied with different pH values, initial dye concentrations, and light intensities from the radiation source to evaluate their effects. The results revealed that the photodegradation was affected by the initial dye concentration, and also showed that the best conditions for the photodegradation reactions of both dyes were an alkaline medium and a light intensity of 80 wt. The films prepared under the conditions reported herein could be promising materials in water purification. Keywords: Photocatalyst, Photodegradation, Rhodamine B, Methylene blue