| Texto completo | |
| Autor(es): |
Cerro-Lopez, Monica
;
Castro-Pastrana, Lucila I.
;
Campos-Delgado, Jessica
;
Rubio-Rosas, Efrain
;
Bustos, Erika
;
Martinez-Huitle, Carlos A.
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Environmental Research; v. 231, p. 12-pg., 2023-06-07. |
| Resumo | |
Mesostructured PbO2/TiO2 materials were synthesized to perform electrocatalysis (as electrooxidation, EO) and photoelectrocatalysis for removing diclofenac (DCF), 15 ppm concentration in 0.1 M NaSO4 solutions, at different pH conditions (3.0, 6.0 and 9.0) by applying 30 mA cm-2. Titania nanotubes (TiO2NTs)-based materials were prepared to synthetize with a massive PbO2 deposit on this support to obtain TiO2NTs/PbO2 and a TiO2NTs: PbO2 material consisting in a dispersed PbO2 deposit on TiO2-NTs that allowed the formation of a hetero-structured surface of combined composition (TiO2 and PbO2). Organics removal (DCF and byproducts) was monitored through UV-vis spectrophotometry and high-performance liquid chromatography (HPLC) during degradation tests. TiO2NTs/PbO2 electrode was tested in both processes, removing DCF at neutral and alkaline solution conditions in EO while an unimportant photoactivity was registered at this material. Conversely, TiO2NTs:PbO2 was used as electrocatalytic material in EO experiments, achieving more than 50% of DCF removal at pH 6.0 by applying 30 mA cm-2. Also, for first time, the synergic effect was investigated when it was exposed to UV irradiation in photoelectrocatalytic experiments, enhancing its efficacy (⁓more than 20%) to remove DCF from a solution with 15 ppm over performance removals achieved (56%) when EO was applied under similar conditions. Chemical Oxygen Demand (COD) analyses showed that significantly higher DCF degradation is reached under photoelectrocatalysis, since COD values decrease a 76% against a 42% decrease achieved with electrocatalysis. Scavenging experiments showed a significant participation on the pharmaceutical oxidation process through the generation of photoholes (h+), hydroxyl radicals and sulfate-based oxidants. (AU) | |
| Processo FAPESP: | 14/50945-4 - INCT 2014: Instituto Nacional de Tecnologias Alternativas para Detecção, Avaliação Toxicológica e Remoção de Micropoluentes e Radioativos |
| Beneficiário: | Maria Valnice Boldrin |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 19/13113-4 - Processos foto (eletro) catalíticos e fotoeletro-fenton para eliminar contaminantes emergentes de águas de rejeito industriais |
| Beneficiário: | Maria Valnice Boldrin |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |