Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid

Autores
Rengifo Herrera, Julian Andres; Blanco, Mirta Noemi; Pizzio, Luis Rene
Año de publicación
2011
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Visible-light-responsive spherical TiO2 particles were prepared by the sol–gel method by adding urea as pore-forming agent and tungstophosphoric acid (TPA) in different ratios (20% and 30% w/w) and by annealing at 500 ◦C for 2 h. Visible light absorption is probably due to WOx formation (i.e. WO3) resulting from the partial degradation of TPA and evidenced by XPS spectra. Besides, 31P NMR and XPS results showed evidence about the existence of mostly unaltered TPA within TiO2 nanoparticles and on their surface, together with lacunar or dimeric species. TPA addition not only affected the optical properties of materials but also produced a strong decrease of their point of zero charge (pHpzc). Results obtained under UV-A irradiation revealed that aqueous malachite green (MG) solutions were efficiently bleached through the oxidative process of N-demethylation being the TiO2 powder containing 30% (w/w) of TPA (TiO2–TPA–30%) (100% of bleaching in 60 min) the most active even than Degussa P-25 (80% of MG bleaching in 60 min). On the other hand, when blue-light irradiation was used, TiO2–TPA–30% powder also revealed the highest photocatalytic bleaching of MG solutions which, as in the case of UVA light irradiation experiments, was oxidized through N-demethylation processes. Finally, experiments carried out using blue-light irradiation under N2 atmosphere showed that aqueous MG solutions were not bleached by TiO2 powders containing TPA
Fil: Rengifo Herrera, Julian Andres . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Fil: Blanco, Mirta Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Fil: Pizzio, Luis Rene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Materia
Heterogeneous Tio2 Photocatalysis;
Visible Light Responsive Tio2
Tungstophosphoric Acid
Malachite Green
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/10007

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network_name_str CONICET Digital (CONICET)
spelling Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acidRengifo Herrera, Julian Andres Blanco, Mirta NoemiPizzio, Luis ReneHeterogeneous Tio2 Photocatalysis;Visible Light Responsive Tio2Tungstophosphoric AcidMalachite Greenhttps://purl.org/becyt/ford/2.4https://purl.org/becyt/ford/2Visible-light-responsive spherical TiO2 particles were prepared by the sol–gel method by adding urea as pore-forming agent and tungstophosphoric acid (TPA) in different ratios (20% and 30% w/w) and by annealing at 500 ◦C for 2 h. Visible light absorption is probably due to WOx formation (i.e. WO3) resulting from the partial degradation of TPA and evidenced by XPS spectra. Besides, 31P NMR and XPS results showed evidence about the existence of mostly unaltered TPA within TiO2 nanoparticles and on their surface, together with lacunar or dimeric species. TPA addition not only affected the optical properties of materials but also produced a strong decrease of their point of zero charge (pHpzc). Results obtained under UV-A irradiation revealed that aqueous malachite green (MG) solutions were efficiently bleached through the oxidative process of N-demethylation being the TiO2 powder containing 30% (w/w) of TPA (TiO2–TPA–30%) (100% of bleaching in 60 min) the most active even than Degussa P-25 (80% of MG bleaching in 60 min). On the other hand, when blue-light irradiation was used, TiO2–TPA–30% powder also revealed the highest photocatalytic bleaching of MG solutions which, as in the case of UVA light irradiation experiments, was oxidized through N-demethylation processes. Finally, experiments carried out using blue-light irradiation under N2 atmosphere showed that aqueous MG solutions were not bleached by TiO2 powders containing TPAFil: Rengifo Herrera, Julian Andres . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Blanco, Mirta Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Pizzio, Luis Rene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaElsevier Science2011-09-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/10007Rengifo Herrera, Julian Andres ; Blanco, Mirta Noemi; Pizzio, Luis Rene; Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid; Elsevier Science; Applied Catalysis B: Environmental; 110; 2; 1-9-2011; 126-1320926-3373enginfo:eu-repo/semantics/altIdentifier/doi/10.1016/j.apcatb.2011.08.034info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0926337311004103info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T09:55:10Zoai:ri.conicet.gov.ar:11336/10007instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 09:55:10.578CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
title Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
spellingShingle Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
Rengifo Herrera, Julian Andres
Heterogeneous Tio2 Photocatalysis;
Visible Light Responsive Tio2
Tungstophosphoric Acid
Malachite Green
title_short Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
title_full Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
title_fullStr Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
title_full_unstemmed Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
title_sort Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid
dc.creator.none.fl_str_mv Rengifo Herrera, Julian Andres
Blanco, Mirta Noemi
Pizzio, Luis Rene
author Rengifo Herrera, Julian Andres
author_facet Rengifo Herrera, Julian Andres
Blanco, Mirta Noemi
Pizzio, Luis Rene
author_role author
author2 Blanco, Mirta Noemi
Pizzio, Luis Rene
author2_role author
author
dc.subject.none.fl_str_mv Heterogeneous Tio2 Photocatalysis;
Visible Light Responsive Tio2
Tungstophosphoric Acid
Malachite Green
topic Heterogeneous Tio2 Photocatalysis;
Visible Light Responsive Tio2
Tungstophosphoric Acid
Malachite Green
purl_subject.fl_str_mv https://purl.org/becyt/ford/2.4
https://purl.org/becyt/ford/2
dc.description.none.fl_txt_mv Visible-light-responsive spherical TiO2 particles were prepared by the sol–gel method by adding urea as pore-forming agent and tungstophosphoric acid (TPA) in different ratios (20% and 30% w/w) and by annealing at 500 ◦C for 2 h. Visible light absorption is probably due to WOx formation (i.e. WO3) resulting from the partial degradation of TPA and evidenced by XPS spectra. Besides, 31P NMR and XPS results showed evidence about the existence of mostly unaltered TPA within TiO2 nanoparticles and on their surface, together with lacunar or dimeric species. TPA addition not only affected the optical properties of materials but also produced a strong decrease of their point of zero charge (pHpzc). Results obtained under UV-A irradiation revealed that aqueous malachite green (MG) solutions were efficiently bleached through the oxidative process of N-demethylation being the TiO2 powder containing 30% (w/w) of TPA (TiO2–TPA–30%) (100% of bleaching in 60 min) the most active even than Degussa P-25 (80% of MG bleaching in 60 min). On the other hand, when blue-light irradiation was used, TiO2–TPA–30% powder also revealed the highest photocatalytic bleaching of MG solutions which, as in the case of UVA light irradiation experiments, was oxidized through N-demethylation processes. Finally, experiments carried out using blue-light irradiation under N2 atmosphere showed that aqueous MG solutions were not bleached by TiO2 powders containing TPA
Fil: Rengifo Herrera, Julian Andres . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Fil: Blanco, Mirta Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Fil: Pizzio, Luis Rene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
description Visible-light-responsive spherical TiO2 particles were prepared by the sol–gel method by adding urea as pore-forming agent and tungstophosphoric acid (TPA) in different ratios (20% and 30% w/w) and by annealing at 500 ◦C for 2 h. Visible light absorption is probably due to WOx formation (i.e. WO3) resulting from the partial degradation of TPA and evidenced by XPS spectra. Besides, 31P NMR and XPS results showed evidence about the existence of mostly unaltered TPA within TiO2 nanoparticles and on their surface, together with lacunar or dimeric species. TPA addition not only affected the optical properties of materials but also produced a strong decrease of their point of zero charge (pHpzc). Results obtained under UV-A irradiation revealed that aqueous malachite green (MG) solutions were efficiently bleached through the oxidative process of N-demethylation being the TiO2 powder containing 30% (w/w) of TPA (TiO2–TPA–30%) (100% of bleaching in 60 min) the most active even than Degussa P-25 (80% of MG bleaching in 60 min). On the other hand, when blue-light irradiation was used, TiO2–TPA–30% powder also revealed the highest photocatalytic bleaching of MG solutions which, as in the case of UVA light irradiation experiments, was oxidized through N-demethylation processes. Finally, experiments carried out using blue-light irradiation under N2 atmosphere showed that aqueous MG solutions were not bleached by TiO2 powders containing TPA
publishDate 2011
dc.date.none.fl_str_mv 2011-09-01
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/10007
Rengifo Herrera, Julian Andres ; Blanco, Mirta Noemi; Pizzio, Luis Rene; Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid; Elsevier Science; Applied Catalysis B: Environmental; 110; 2; 1-9-2011; 126-132
0926-3373
url http://hdl.handle.net/11336/10007
identifier_str_mv Rengifo Herrera, Julian Andres ; Blanco, Mirta Noemi; Pizzio, Luis Rene; Photocatalytic bleaching of aqueous malachite green solutions by UV-A and blue-light-illuminated TiO2 spherical nanoparticles modified with tungstophosphoric acid; Elsevier Science; Applied Catalysis B: Environmental; 110; 2; 1-9-2011; 126-132
0926-3373
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1016/j.apcatb.2011.08.034
info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0926337311004103
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Elsevier Science
publisher.none.fl_str_mv Elsevier Science
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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