Effect of exopolysaccharides on photocatalytic activity of ZnO nanoparticles

Zinc oxide nanoparticles (ZnO NPs) are largely used in consumer products and industrial applications. The increased use of such materials may lead to its release into the environment. The study used chemically synthesized ZnO NPs and characterized by using UV–visible spectrophotometer, scanning electron microscopy, particle size analyzer and X-ray diffraction (XRD) analysis. The mean diameter of the particles was found to be 55 ± 1.2 nm. The XRD patterns exhibited hexagonal structure for ZnO NPs. The photocatalytic property of ZnO NPs was evaluated based on the UV–vis spectra changes of the methylene blue solution as a function of reaction time in the presence of ZnO NPs under visible light. The study suggests that ZnO NPs can be used as an efficient photocatalyst and the environmental factor such as exopolysaccharides could mask the photocatalytic activity of NPs.