Photoelectrocatalytic removal of bromate using Ti/TiO2 coated as a photocathode

Environ Sci Technol. 2009 Oct 1;43(19):7496-502. doi: 10.1021/es803366d.

Abstract

These studies represent the rare use of a TiO2 material as a photocathode and the first application of photoelectrocatalysis for BrO3- removal. Photoelectrocatalytic reduction of BrO3- to Br- can reach 70% at neutral pH under an applied potential of -0.20 V versus SCE (saturated calomel electrode) after 75 min on the irradiated nanoporous thin-film TiO2-coated working electrode, which presented a flat band potential of -0.0274 V versus SCE. Regardless of the potential applied in these experiments, no BrO3- removal was observed in the counter electrode compartment or during electrolysis or photocatalysis, confirming that reduction of BrO3- to Br requires the combination of a negative potential (ideally near -0.20 V) and ultraviolet irradiation of the Ti/TiO2 electrode. The process was selective for BrO3- removal in that this process did not significantly reduce levels of Ca2+ and Mg2+ in drinking waters.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bromates / chemistry*
  • Catalysis
  • Electrochemical Techniques
  • Electrodes
  • Photochemistry
  • Titanium / chemistry*
  • Water Pollutants, Chemical / chemistry*
  • Water Purification / methods*

Substances

  • Bromates
  • Water Pollutants, Chemical
  • titanium dioxide
  • Titanium