Efficient photo–catalytic degradation of malachite green using nickel tungstate material as photo–catalyst

The present study focused on the evaluation of photo-catalytic and photo–electrochemical properties of the photo–catalyst based on nickel tungstate material prepared by a nitrate method through the degradation of malachite green (MG) dye's. The effect of catalyst loading and dye concentration was examined. Physico–chemical, optical, electrical, electrochemical, and photo–electrochemical properties of the prepared material were analyzed by X-ray diffraction (XRD), fourier transform–infrared spectroscopy (FTIR), BET analysis, optical reflectance diffuse (DR), scanning electron microscopy (SEM/EDX), electrical conductivity, cyclic voltammetry (CV), current intensity, mott–shottky, and nyquist. XRD revealed the formation of monoclinic structure with a small particle size. BET surface area of the sample was around 10 m2/g. The results show that the degradation of MG was more than 80%, achieved after 3 h of irradiation at pH 4.6 and with a catalyst loading of 75 mg. Also, it was found that the dye photo–degradation obeyed the pseudo-first order kinetic via Langmuir Hinshelwood model.