Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Evidence for H2O2 generation during the TiO2-assisted photodegradation of dyes in aqueous dispersions under visible light illumination
Autore:
Wu, TX; Liu, GM; Zhao, JC; Hidaka, H; Serpone, N;
Indirizzi:
Chinese Acad Sci, Inst Photog Chem, Beijing 100101, Peoples R China Chinese Acad Sci Beijing Peoples R China 100101 100101, Peoples R China Iwaki,Meisei Univ, Frontier Res Ctr Earth Environm Protect, Hino, Tokyo 191 Iwaki Meisei Univ Hino Tokyo Japan 191 Environm Protect, Hino, Tokyo 191 Concordia Univ, Dept Chem & Biochem, Montreal, PQ H3G 1M8, Canada Concordia Univ Montreal PQ Canada H3G 1M8 m, Montreal, PQ H3G 1M8, Canada
Titolo Testata:
JOURNAL OF PHYSICAL CHEMISTRY B
fascicolo: 23, volume: 103, anno: 1999,
pagine: 4862 - 4867
SICI:
1520-6106(19990610)103:23<4862:EFHGDT>2.0.ZU;2-F
Fonte:
ISI
Lingua:
ENG
Soggetto:
COLLOIDAL TIO2 PARTICLES; PHOTOASSISTED DEGRADATION; ENVIRONMENTAL PHOTOCHEMISTRY; SEMICONDUCTOR SURFACES; ELECTRON-TRANSFER; CATIONIC DYES; EXCITED-STATE; ACIDIC MEDIA; RHODAMINE-B; IRRADIATION;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
28
Recensione:
Indirizzi per estratti:
Indirizzo: Zhao, JC Chinese Acad Sci, Inst Photog Chem, Beijing 100101, Peoples R China Chinese Acad Sci Beijing Peoples R China 100101 Peoples R China
Citazione:
T.X. Wu et al., "Evidence for H2O2 generation during the TiO2-assisted photodegradation of dyes in aqueous dispersions under visible light illumination", J PHYS CH B, 103(23), 1999, pp. 4862-4867

Abstract

Photodegradation of a series of dyes (Rhodamine B, Orange II, Sulfu-rhodamine B, Fluorescein, Alizarin red, Squarylium cyanine, and Eosin) in the presence of TiO2 particles under air-equilibrated controlled conditions and visible light illumination led to the formation of hydrogen peroxide. Combined with chemical oxygen demand (COD) measurements and in situ adsorption of added H2O2, the results reveal that H2O2 is a perfidious intermediate species in the process of dye photodegradation. The formation rate of H2O2 depends on the rate of dye degradation. It can also be decomposed by TiO2 particles under visible light irradiation because of a TiO2/H2O2 surface complex. H2O2 was detected because its formation rate was greater than its decomposition rate; failing this, H2O2 would not be observed. Its decomposition rate depends on the amount of substrates or intermediates formed during dye degradation and adsorbed on the surface of the TiO2 particles. The greater the degradation rate of the dye or the greater the quantity of substrates or intermediates adsorbed on the TiO2 surface, the less is the depletion of H2O2 with the consequence that a large quantity of H2O2 accumulates in the solution bulk permitting its facile detection. Also, pH appears to play a beneficial role in the observation of H2O2 formed.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/09/20 alle ore 19:26:47