Photoelectrocatalytic degradation of methylene blue using F doped TiO2 photoelectrode under visible light irradiation.
Chemosphere
; 185: 574-581, 2017 Oct.
Article
em En
| MEDLINE
| ID: mdl-28719876
ABSTRACT
Photoelectrocatalysis (PEC) has attracted great interest due to cost effectiveness and high efficiency in water treatment. In this study, F doped TiO2 (F-TiO2) photoelectrodes with honeycomb like morphology were prepared, and the PEC performance was investigated. F-TiO2 particles that showed enhanced absorption of visible light were synthesized via a sol-gel method. F-TiO2 particles were anchored onto the surface of F-doped SnO2 glass by a screen-printing method to prepare the F-TiO2 photoelectrodes. The PEC performance of the F-TiO2 photoelectrodes was investigated via the degradation of methylene blue (MB) under visible light irradiation. The results show that the F-TiO2 photoelectrodes exhibited an excellent PEC performance that was affected by the F doping content, applied bias and solution pH. A maximum decolorization percentage of 97.8% was achieved by the FT-15 photoelectrode, with a 1.4 V bias at pH 9.94 after 4.0 h of visible light irradiation. The high PEC performance of the F-TiO2 photoelectrodes is mainly ascribed to the efficient separation of electron-hole (e--h+) pairs and the creation of active radicals such as hydroxyl radicals (OH). The PEC decolorization kinetic data were analyzed using the first-order kinetic model and the Langmuir-Hinshelwood (L-H) model. The data indicates that the PEC degradation of MB molecules mainly occurred on the surface of the F-TiO2 photoelectrodes, and the MB molecules were discolored mainly by h+ (41.5%) and OH (46.5%). In addition, 8.2% of the MB molecules were discolored by other oxidative species, and 3.8% of the MB molecules were discolored by self-sensitized oxidation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Titânio
/
Poluentes Químicos da Água
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Purificação da Água
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Azul de Metileno
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article