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

Environ Sci Pollut Res Int. 2017 Mar;24(7):6481-6491. doi: 10.1007/s11356-016-8296-3. Epub 2017 Jan 10.

Abstract

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.

Keywords: Malachite green; Nickel tungsten; Photo–degradation; Photo–electrochemical properties; Visible light.

MeSH terms

  • Adsorption
  • Catalysis
  • Coloring Agents / analysis*
  • Coloring Agents / chemistry
  • Coloring Agents / radiation effects
  • Environmental Restoration and Remediation
  • Light*
  • Microscopy, Electron, Scanning
  • Nickel / chemistry*
  • Particle Size
  • Rosaniline Dyes / analysis*
  • Rosaniline Dyes / chemistry
  • Rosaniline Dyes / radiation effects
  • Spectroscopy, Fourier Transform Infrared
  • Surface Properties
  • Tungsten Compounds / chemistry*
  • Water Pollutants, Chemical / analysis*
  • Water Pollutants, Chemical / chemistry
  • Water Pollutants, Chemical / radiation effects
  • X-Ray Diffraction

Substances

  • Coloring Agents
  • Rosaniline Dyes
  • Tungsten Compounds
  • Water Pollutants, Chemical
  • malachite green
  • Nickel