Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure
Autor(a) principal: | |
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Data de Publicação: | 2018 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1007/s10854-018-9799-0 http://hdl.handle.net/11449/171332 |
Resumo: | The increase in photocatalytic activity of reduced graphene oxide–TiO2 heterostructures under ultraviolet and visible illumination is already well known, as the photocatalyst mechanism modifications with heterostructure formation. However, which step in the degradation mechanism is modified with reduced graphene oxide–TiO2 heterostructure formation has been not demonstrated yet. These specific modifications are caused by the alteration in reactive oxygen species production. In this way, the goal of this study is defined which reactive oxygen species are produced by reduced graphene oxide–TiO2 heterostructure in the photocatalytic mechanism. A fast synthesis method to obtain this heterostructure by the microwave-assisted solvothermal method is presented, obtaining an improvement of photocatalytic efficiency, under UV and visible illumination. The non-hydrolytic method favors a better distribution of TiO2 nanoparticles around the reduced graphene oxide structure and inhabits the charge carrier recombination, showing a faster electron transfer than TiO2 samples. The RhB discoloration mechanism confirms that the reduced graphene oxide presence modifies the main reactive oxygen species produced. Under UV illumination, O2H* radical is the dominant reactive oxygen species produced by TiO2. For the heterostructure, the direct oxidation by oxygen vacancy is the primary mechanism step. Under visible illumination, O2H* is the main reactive oxygen species for both materials. The results present a better understanding of principal reasons related to the improvement in photocatalytic activity and could be useful in semiconductor heterostructure design. |
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Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructureThe increase in photocatalytic activity of reduced graphene oxide–TiO2 heterostructures under ultraviolet and visible illumination is already well known, as the photocatalyst mechanism modifications with heterostructure formation. However, which step in the degradation mechanism is modified with reduced graphene oxide–TiO2 heterostructure formation has been not demonstrated yet. These specific modifications are caused by the alteration in reactive oxygen species production. In this way, the goal of this study is defined which reactive oxygen species are produced by reduced graphene oxide–TiO2 heterostructure in the photocatalytic mechanism. A fast synthesis method to obtain this heterostructure by the microwave-assisted solvothermal method is presented, obtaining an improvement of photocatalytic efficiency, under UV and visible illumination. The non-hydrolytic method favors a better distribution of TiO2 nanoparticles around the reduced graphene oxide structure and inhabits the charge carrier recombination, showing a faster electron transfer than TiO2 samples. The RhB discoloration mechanism confirms that the reduced graphene oxide presence modifies the main reactive oxygen species produced. Under UV illumination, O2H* radical is the dominant reactive oxygen species produced by TiO2. For the heterostructure, the direct oxidation by oxygen vacancy is the primary mechanism step. Under visible illumination, O2H* is the main reactive oxygen species for both materials. The results present a better understanding of principal reasons related to the improvement in photocatalytic activity and could be useful in semiconductor heterostructure design.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado do Rio Grande do SulFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)IQ UNESP São Paulo State University, Av. Prof. Francisco Degni, 55 - Jardim QuitandinhaIBILCE UNESP São Paulo State UniversityEmbrapa InstrumentationPhysics Institute of São Carlos USPDQ UFSCar Federal University of São CarlosIQ UNESP São Paulo State University, Av. Prof. Francisco Degni, 55 - Jardim QuitandinhaIBILCE UNESP São Paulo State UniversityCNPq: #444926/2014-3Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul: CEPID 2013/07296-2Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul: grant #2012/26671-9FAPESP: grant #2014/11410-8Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul: grant #2014/17343-0Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul: grant #2015/04511-5Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul: grant #2017/01267-1Universidade Estadual Paulista (Unesp)Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)Universidade de São Paulo (USP)Universidade Federal de São Carlos (UFSCar)Byzynski, Gabriela [UNESP]Volanti, Diogo P. [UNESP]Ribeiro, CauêMastelaro, Valmor R.Longo, Elson2018-12-11T16:54:55Z2018-12-11T16:54:55Z2018-10-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article17022-17037application/pdfhttp://dx.doi.org/10.1007/s10854-018-9799-0Journal of Materials Science: Materials in Electronics, v. 29, n. 19, p. 17022-17037, 2018.1573-482X0957-4522http://hdl.handle.net/11449/17133210.1007/s10854-018-9799-02-s2.0-850514980822-s2.0-85051498082.pdf23547399804067250000-0001-9315-9392Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengJournal of Materials Science: Materials in Electronics0,503info:eu-repo/semantics/openAccess2024-01-20T06:30:07Zoai:repositorio.unesp.br:11449/171332Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T23:28:38.279700Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
title |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
spellingShingle |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure Byzynski, Gabriela [UNESP] |
title_short |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
title_full |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
title_fullStr |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
title_full_unstemmed |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
title_sort |
Direct photo-oxidation and superoxide radical as major responsible for dye photodegradation mechanism promoted by TiO2–rGO heterostructure |
author |
Byzynski, Gabriela [UNESP] |
author_facet |
Byzynski, Gabriela [UNESP] Volanti, Diogo P. [UNESP] Ribeiro, Cauê Mastelaro, Valmor R. Longo, Elson |
author_role |
author |
author2 |
Volanti, Diogo P. [UNESP] Ribeiro, Cauê Mastelaro, Valmor R. Longo, Elson |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Universidade de São Paulo (USP) Universidade Federal de São Carlos (UFSCar) |
dc.contributor.author.fl_str_mv |
Byzynski, Gabriela [UNESP] Volanti, Diogo P. [UNESP] Ribeiro, Cauê Mastelaro, Valmor R. Longo, Elson |
description |
The increase in photocatalytic activity of reduced graphene oxide–TiO2 heterostructures under ultraviolet and visible illumination is already well known, as the photocatalyst mechanism modifications with heterostructure formation. However, which step in the degradation mechanism is modified with reduced graphene oxide–TiO2 heterostructure formation has been not demonstrated yet. These specific modifications are caused by the alteration in reactive oxygen species production. In this way, the goal of this study is defined which reactive oxygen species are produced by reduced graphene oxide–TiO2 heterostructure in the photocatalytic mechanism. A fast synthesis method to obtain this heterostructure by the microwave-assisted solvothermal method is presented, obtaining an improvement of photocatalytic efficiency, under UV and visible illumination. The non-hydrolytic method favors a better distribution of TiO2 nanoparticles around the reduced graphene oxide structure and inhabits the charge carrier recombination, showing a faster electron transfer than TiO2 samples. The RhB discoloration mechanism confirms that the reduced graphene oxide presence modifies the main reactive oxygen species produced. Under UV illumination, O2H* radical is the dominant reactive oxygen species produced by TiO2. For the heterostructure, the direct oxidation by oxygen vacancy is the primary mechanism step. Under visible illumination, O2H* is the main reactive oxygen species for both materials. The results present a better understanding of principal reasons related to the improvement in photocatalytic activity and could be useful in semiconductor heterostructure design. |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018-12-11T16:54:55Z 2018-12-11T16:54:55Z 2018-10-01 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1007/s10854-018-9799-0 Journal of Materials Science: Materials in Electronics, v. 29, n. 19, p. 17022-17037, 2018. 1573-482X 0957-4522 http://hdl.handle.net/11449/171332 10.1007/s10854-018-9799-0 2-s2.0-85051498082 2-s2.0-85051498082.pdf 2354739980406725 0000-0001-9315-9392 |
url |
http://dx.doi.org/10.1007/s10854-018-9799-0 http://hdl.handle.net/11449/171332 |
identifier_str_mv |
Journal of Materials Science: Materials in Electronics, v. 29, n. 19, p. 17022-17037, 2018. 1573-482X 0957-4522 10.1007/s10854-018-9799-0 2-s2.0-85051498082 2-s2.0-85051498082.pdf 2354739980406725 0000-0001-9315-9392 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Journal of Materials Science: Materials in Electronics 0,503 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
17022-17037 application/pdf |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
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1808129524243628032 |