The Role of Chloride in Trichloroethylene on its Photodegradation by Metallised (Ag, Pt) Titanium Dioxide

  • Dr Cissillia Young, Institute of Environmental Science and Engineering, Nanyang Technological University, Singapore
  • Assoc/Prof Tuti Lim, Institute of Environmental Science and Engineering, Nanyang Technological University, Singapore
  • Dr Ken Chiang, ARC Centre for Functional Nanomaterials, University of New South Wales, Australia
  • Dr Jason Scott, ARC Centre for Functional Nanomaterials, University of New South Wales, Australia
  • Prof Rose Amal, ARC Centre for Functional Nanomaterials, University of New South Wales, Australia

    • The presence of nanosized metal deposits on the surface of titanium dioxide is generally beneficial for photocatalytic oxidation. Platinum deposits regularly improve photocatalytic performance moreso than silver deposits, although this was not the case for the gas-phase photodegradation of trichloroethylene (TCE) in this study. Here, Pt deposits were detrimental for photoactivity, irrespective of the loading, while Ag loadings up to 1 at% were beneficial. XPS spectra of fresh and used metallised titanium dioxide indicated both an increase in the percentage of oxidised metal on the surface as well as the presence of both organic and inorganic chloride species following TCE photodegradation. The contribution of chloride to the respective positive and negative effects of Ag and Pt on the photodegradation of TCE is discussed in light of these findings as is the influence of deposit characteristics on the extent of the effect.