Efficient photocatalytic degradation of organic dye from aqueous solutions over zinc oxide incorporated nanocellulose under visible light irradiation

Abstract

Abstract Increased growth of textile industries leads to the tremendous accumulation of dyes on water and surrounding environments. This terrific increase of dyes is the major cause of water pollution which in turn adversely affects the aquatic lives and the balance of our ecosystem. Purpose of the present study is to report the synthesis and characterization of a composite namely zinc oxide incorporated nanocellulose (ZnO/NC) for effective degradation of an anionic dye, Congo red. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunaeur, Emmett and Teller (BET) surface area analysis and scanning electron microscopy (SEM) studies have helped to characterize the composite. The optical properties of the samples were studied by UV-Visible spectroscopy. Feasibility of the photocatalyst in the degradation of Congo red was tested. Experimental conditions such as time of contact, concentration of the dye solution, catalyst dosage, pH were altered to find out the optimum conditions of degradation. The optimum pH was found to be 5.5 and dosage of ZnO/NC was optimized as 0.075 g for a dye concentration of 20 ppm. Equilibrium was attained at 120 min. The studies reveal that the photocatalyst ZnO/NC is efficient for the photodegradation of Congo red. Photodegradation was due to electron hole interaction between metal oxides and nanocellulose.