TiO2-assisted photodegradation of dyes: A study of two competitive primary processes in the degradation of RB in an aqueous TiO2 colloidal solution
✍ Scribed by Ping Qu; Jincai Zhao; Tao Shen; Hisao Hidaka
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 382 KB
- Volume
- 129
- Category
- Article
- ISSN
- 1381-1169
No coin nor oath required. For personal study only.
✦ Synopsis
Ž X X . The photocatalytic degradation of rhodamine B N, N, N , N -tetraethylrhodamine, RB had been studied in a colloidal TiO solution under both UV and visible light irradiation. Two different photodegradation processes of RB, photobleaching 2 and N-deethylation, were examined in detail. The N-deethylation of RB was attributed to the oxidation by HOO P or OH P radicals generated from the dye-photosensitized andror TiO catalyzed reactions; while the photobleaching of RB was 2 found to occur via dye cationic radical. The aromatic rings of RB cannot be destroyed in the absence of oxygen under visible 3q 2q Ž . light irradiation. Various additives, Fe , EDTA, MV , different atmosphere O and N , time-resolved laser flash 2 2 Ž . photolysis and spin trapping electron paramagnetic resonance ESR were used to determine the possible mechanisms involved. q 1998 Elsevier Science B.V.