| Attributs | Valeurs |
|---|
| type
| |
| Is Part Of
| |
| Subject
| |
| Title
| - Highly Enhanced PhotoreductiveDegradation of PerchlorinatedCompounds on Dye-SensitizedMetal/TiO2 under Visible Light
|
| has manifestation of work
| |
| related by
| |
| Author
| |
| Abstract
| - This study reports an example of visible-light photocatalystbased on TiO2 modified by ruthenium-complex sensitizersand noble metal deposits. The photodegradation oftrichloroacetate (TCA) and carbon tetrachloride was usedas a probe reaction for evaluating the visible lightactivity of the photocatalyst under the illumination of λ >420 nm. Photodeposition of platinum nanoparticles on dye-sensitized TiO2 (Pt/TiO2/RuIIL3) drastically enhanced thedegradation rate of TCA and CCl4. The visible light reactivityof Pt/TiO2/RuIIL3 was optimal with [RuIIL3] = 10 μM,[TiO2] = 0.5 g/L, and Pt loading of about 0.2 wt %. Althoughno electron donors to regenerate the oxidized Ru-sensitizers were added in the aqueous suspension, thephotoreductive dechlorination of perchlorinated compoundsproceeded far beyond the stoichiometric limit of theinitial sensitizer concentration. Water acted as an electrondonor to regenerate the sensitizer with a concurrentproduction of dioxygen. On the other hand, Pt/TiO2/RuIIL3was completely inactive in the presence of dissolved oxygenand the in-situ generated dioxygen gradually deceleratedthe dechlorination rate. Conduction band electronstransferred to O2 in preference to CCl4 and TCA on Ptdeposits. Other noble metals (Ag, Au, and Pd) depositedon TiO2 showed a better oxygen-tolerance but less visible-light reactivity than Pt/TiO2/RuIIL3. Effects of metal loadingon the visible light activity and its implications for theefficient visible-light photocatalyst development are discussed.
|
| article type
| |
| is part of this journal
| |
