Facile synthesis of PbWO4: applications in photoluminescence and photocatalytic degradation of organic dyes under visible light

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 5:136 Pt B:348-55. doi: 10.1016/j.saa.2014.09.038. Epub 2014 Oct 6.

Abstract

Stolzite polymorph of PbWO4 catalyst was prepared by the facile room temperature precipitation method. Structural parameters were refined by the Rietveld analysis using powder X-ray data. PbWO4 was crystallized in the scheelite-type tetragonal structure with space group I41/a (No. 88). Field emission scanning electron microscopy revealed leaf like morphology. Photoluminescence spectra exhibit broad blue emission (425 nm) under the excitation of 356 nm. The photocatalytic degradation of Methylene blue, Rhodamine B and Methyl orange dyes were measured under visible illumination. The 100% dye degradation was observed for MB and RhB dyes within 60 and 105 min. The rate constant was found to be in the decreasing order of MB>RhB>MO which followed the 1st order kinetic mechanism. Therefore, PbWO4 can be a potential candidate for blue component in white LEDs and also acts as a catalyst for the treatment of toxic and non-biodegradable organic pollutants in water.

Keywords: PbWO(4); Phosphor; Photocatalytic degradation; Rietveld refinement; Scheelite structure.

MeSH terms

  • Adsorption
  • Catalysis / radiation effects
  • Coloring Agents / chemistry*
  • Coloring Agents / radiation effects
  • Kinetics
  • Light*
  • Luminescence*
  • Methylene Blue / chemistry
  • Microscopy, Electron, Scanning
  • Organic Chemicals / chemistry*
  • Organic Chemicals / radiation effects
  • Photolysis* / radiation effects
  • Powders
  • Recycling
  • Rhodamines / chemistry
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • Temperature
  • Tungsten Compounds / chemical synthesis*
  • Tungsten Compounds / chemistry
  • X-Ray Diffraction

Substances

  • Coloring Agents
  • Organic Chemicals
  • Powders
  • Rhodamines
  • Tungsten Compounds
  • lead tungstate
  • rhodamine B
  • Methylene Blue