Photocatalytic degradation of organic dye using nano ZnO

Photocatalytic degradation of methylene blue was investigated using nanocrystalline ZnO prepared by chemical precipitation and thermal decomposition routes. In both preparation routes zinc acetate dihydrate was used as the precursor. In the case of precipitation route, sodium hydroxide was used as the precipitating agent at room temperature, but in thermal decomposition method the precursor was just calcined at 450°C for 30 min. The structural and morphological properties were studied by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). The sample prepared by precipitation route exhibits higher photocatalytic activity than that by thermal decomposition method and the reasons for the enhanced photocatalytic activity have been discussed in detail.