Photocatalytic treatment of MB Dye using ZnO Nanoparticles

Abstract

Environment pollution has become primary concern for human health. Among various types of pollution, water pollution is the major cause for the spreading of various precarious diseases among humans as well as animals [1]. Water pollution become serious problem with the industrial development because of the use of organic dye, treatment of waste water which comes from textile, paper printing and dyeing industry which has become imperative day by day [2]. Wastewater from these industries is not gladly biodegradable. For environmental protection as well as human health removing these organic pollutants from wastewater is foremost. Semiconducting zinc oxide (ZnO) show good photocatalyst activity among various oxides [3]. To treat these pollutants from earth surface is foremost for the survival of human as well as living organisms in under water. Semiconducting ZnO have several applications such as-drug delivery, sensor, microwave devices, electronic devices, catalyst, biosensor, and etc. ZnO is known as good catalyst to eliminate the various contaminates for methylene blue dye degradation due to large band and stability [4]. UV light was used for the photocatalytic activity as energy source. When brighten with a light source, the photocatalyst activity generates electron-hole pair, in conduction band free electron is generated and leave positive hole in valence band [5]. Various toxic chemicals can be eliminated by this method. The main motive of this work, is to traverse the potential of ZnO even as a photocatalyst under Ultra-Violet radiation for the oxidation of textile dyes [6].

Fig.1A the XRD patterns of ZnO sample. All the peaks are well matched with the JCPDS card No-36-1451. The structure of ZnO is wurzite hexagonal. The crystallite size, interplaner spacing, strain and dislocation density of ZnO is 36.27 nm, 2.47 nm, 0.179 and 0.0075 nm^-2 respectively. To assess the photocatalytic production of ZnO sample towards the degradation of MB dye, 5 mg of ZnO was dissolve in 100 ml of 5 ppm solution of MB Dye. Samples were taken after every 3 minutes. Samples were then centrifuged and then UV-Vis spectroscopy was used to evaluate the percentage degradation of Dye.

Fig.1 A Show the Xay-diffraction  pattern of ZnO. B Degradation of Methylene Blue dye by ZnO.