Evidences of the Electrochemical Production of Sulfate Radicals at Cathodically Polarized TiO2 Nanotubes Electrodes

This work presents a novel approach for cathodically polarized TiO2 nanotube electrodes in electrochemical advanced oxidation processes generating sulfate radicals. Although TiO2 do not offer electrochemical response at the anodic region in the dark, its simple self-doping can enable oxidation capac...

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Detalles Bibliográficos
Autores: Bessegato, Guilherme G. [UNESP], Zanoni, Maria Valnice Boldrin [UNESP], Tremiliosi-Filho, Germano, Lindino, Cleber A.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/190627
Acceso en línea:http://dx.doi.org/10.1007/s12678-019-00525-6
http://hdl.handle.net/11449/190627
Access Level:acceso abierto
Palabra clave:Dye oxidation
Electrochemical advanced oxidation processes
Electrochemically activated sulfate
Persulfate
TiO2 self-doping
Descripción
Sumario:This work presents a novel approach for cathodically polarized TiO2 nanotube electrodes in electrochemical advanced oxidation processes generating sulfate radicals. Although TiO2 do not offer electrochemical response at the anodic region in the dark, its simple self-doping can enable oxidation capacity. Cathodically polarized TiO2 electrode (CP-TNT) was applied in the electrolysis of p-nitrosodimethylaniline dye in sulfate and nitrate aqueous electrolytes, showing much better decolorization efficiency in the presence of sulfate ions. Another evidence of SO4 •− generation was the detection of persulfate ions (SO4 •− + SO4 •− → S2O8 2−) formed during bulk electrolysis of a sulfate aqueous solution (38 μmol L−1 S2O8 2− after 30 min). These results open the way for application of CP-TNT electrodes in EAOPs as an alternative for highly cost anodes for electrochemical generation of active sulfate species for degradation of organic contaminants. [Figure not available: see fulltext.]