Sonochemical synthesis and visible light photocatalytic behavior of CdSe and CdSe/TiO2 nanoparticles

Wing Kei HO, Jimmy C. YU

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141 Citations (Scopus)

Abstract

This paper reports an ultrasound-driven approach in the synthesis of CdSe and CdSe sensitized TiO2 and also the their photocataltyic behavior of these materials under visible light. The results show that the CdSe/TiO2 coupled system has a much higher photocatalytic activity than that of pure TiO2 and CdSe in the degradation of 4-chlorophenol under visible light irradiation. The CdSe nanoparticles which act as a photosensitizer not only extend the spectral response of TiO2 to the visible region but also reduce the charge recombination. Blue shift in the absorption onset confirms the size quantization of the CdSe nanoparticles under sonochemical synthesis. The quantum size effect alters the conduction and valence bands of CdSe particles to the appropriate energy levels in the coupled semiconductor system. This can make the electron injection from CdSe to TiO2 more efficient and increase the degree of charge separation significantly, thereby enhancing the performance of the new coupled photocatalyst system. Copyright © 2005 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)268-274
JournalJournal of Molecular Catalysis A: Chemical
Volume247
Issue number1-2
DOIs
Publication statusPublished - 2006

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Nanoparticles
Electron injection
Photosensitizing Agents
Photocatalysts
Valence bands
Conduction bands
Electron energy levels
Ultrasonics
Irradiation
Semiconductor materials
Degradation
4-chlorophenol

Bibliographical note

Ho, W. K.; Yu, J. C. (2006). Sonochemical synthesis and visible light photocatalytic behavior of CdSe and CdSe/TiO2 nanoparticles. J. Molecular Catal. A: Chemcial, 247(1-2), 268-274. doi: 10.1016/j.molcata.2005.11.057

Keywords

  • Titanium dioxide
  • Cadmium selenide
  • Sonochemical
  • Photocatalytic