New and effective ZnO and Zn3(VO4)2 visible nano photocatalysts with enhanced photocatalytic performance

Abstract

In this work a new, simple and low cost method for synthesis of zinc oxide and zinc vanadate nanoparticles was proposed. The as-prepared nanoparticles were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, Field emission scanning electron microscopy and electron dispersive X-ray spectroscopy. For evaluation of photocatalytic activity of these nanoparticles, some experiments under various conditions were carried out on the methylene blue as a pollutant model under visible light irradiation. Based on the obtained results, both photocatalysts have good efficacy for photo degradation of methylene blue, but zinc vanadate exhibits higher efficiency than zinc oxide for the decoloration of methylene blue. The higher visible-light-driven photocatalytic activity of zinc vanadate may be due to the more absorption of visible light by this nanoparticle. Zinc vanadate was also used successfully for the photo degradation of methyl red as a model of anionic dyes. Moreover, a preliminary kinetic study along with proposed photo degradation mechanism is included in this study.