On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide
Autor(a) principal: | |
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Data de Publicação: | 2017 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1016/j.electacta.2017.05.112 http://hdl.handle.net/11449/174633 |
Resumo: | The electrical and morphological properties as well as the assessment of self organized TiO2 nanotubes (TiO2-NTs) as supercapacitors were carried out for the first time for samples grown in organic medium and annealed in a microwave oven (MO) through a hybrid thermal heating. These samples were compared to those obtained by heat treatment in a conventional muffle furnace (MF). No significant differences were observed in the nanotubular morphology, crystalline structure (anatase phase) and of the band gap values; however, samples annealed in a MO showed an improvement in the donor density and a higher flat band potential. After a cathodic pre-treatment (–1.4 V vs. NHE for 60 s) to generate oxygen vacancies/Ti3+ (black TiO2) the MO annealed samples exhibited a superior areal capacitance than the MF annealed samples, even after 5000 cycles of galvanostatic charge-discharge experiments. The improved performance of the MO annealed samples is related to a higher amount of produced oxygen vacancies/Ti3+ on the surface of TiO2-NT. As the generated surface oxygen vacancies are unstable, reactions with adsorbed H2O lead to a more hydroxylated surface layer. Electrochemical impedance spectroscopy (EIS) measurements of the as-prepared black TiO2 exhibited a significant diminishment of the charge transfer resistance for the MO annealed samples; however, assessment of the water aging stability of these pre-treated films resulted in increasing values for the charge transfer resistance. The thermally grown oxide interface layer formed on the Ti substrate showed for both annealing methods similar EIS profiles and seems it has no influence on the values obtained for the areal capacitance. The results suggest that microwave annealing is an interesting option to convert amorphous TiO2-NTs into the crystalline anatase phase, especially because this procedure is very rapid and facile, resulting in an improvement of their areal capacitance after a cathodic pre-treatment. |
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On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxidebarrier oxideblack TiO2microwave ovenoxygen vacancysupercapacitorTiO2 nanotubesThe electrical and morphological properties as well as the assessment of self organized TiO2 nanotubes (TiO2-NTs) as supercapacitors were carried out for the first time for samples grown in organic medium and annealed in a microwave oven (MO) through a hybrid thermal heating. These samples were compared to those obtained by heat treatment in a conventional muffle furnace (MF). No significant differences were observed in the nanotubular morphology, crystalline structure (anatase phase) and of the band gap values; however, samples annealed in a MO showed an improvement in the donor density and a higher flat band potential. After a cathodic pre-treatment (–1.4 V vs. NHE for 60 s) to generate oxygen vacancies/Ti3+ (black TiO2) the MO annealed samples exhibited a superior areal capacitance than the MF annealed samples, even after 5000 cycles of galvanostatic charge-discharge experiments. The improved performance of the MO annealed samples is related to a higher amount of produced oxygen vacancies/Ti3+ on the surface of TiO2-NT. As the generated surface oxygen vacancies are unstable, reactions with adsorbed H2O lead to a more hydroxylated surface layer. Electrochemical impedance spectroscopy (EIS) measurements of the as-prepared black TiO2 exhibited a significant diminishment of the charge transfer resistance for the MO annealed samples; however, assessment of the water aging stability of these pre-treated films resulted in increasing values for the charge transfer resistance. The thermally grown oxide interface layer formed on the Ti substrate showed for both annealing methods similar EIS profiles and seems it has no influence on the values obtained for the areal capacitance. The results suggest that microwave annealing is an interesting option to convert amorphous TiO2-NTs into the crystalline anatase phase, especially because this procedure is very rapid and facile, resulting in an improvement of their areal capacitance after a cathodic pre-treatment.Universidade Federal de São Carlos, Departamento de Química, C.P. 676Universidade Estadual Paulista (UNESP) Instituto de Química de Araraquara Departamento de Físico-QuímicaUniversidade Estadual Paulista (UNESP) Instituto de Química de Araraquara Departamento de Físico-QuímicaUniversidade Federal de São Carlos (UFSCar)Universidade Estadual Paulista (Unesp)Silva, Diego D.Sánchez-Montes, IsaacHammer, Peter [UNESP]Aquino, José M.2018-12-11T17:12:11Z2018-12-11T17:12:11Z2017-08-10info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article165-172application/pdfhttp://dx.doi.org/10.1016/j.electacta.2017.05.112Electrochimica Acta, v. 245, p. 165-172.0013-4686http://hdl.handle.net/11449/17463310.1016/j.electacta.2017.05.1122-s2.0-850197700392-s2.0-85019770039.pdf64668410235061310000-0002-3823-0050Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengElectrochimica Acta1,439info:eu-repo/semantics/openAccess2023-12-31T06:20:55Zoai:repositorio.unesp.br:11449/174633Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T21:47:35.428523Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
title |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
spellingShingle |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide Silva, Diego D. barrier oxide black TiO2 microwave oven oxygen vacancy supercapacitor TiO2 nanotubes |
title_short |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
title_full |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
title_fullStr |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
title_full_unstemmed |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
title_sort |
On the supercapacitor performance of microwave heat treated self organized TiO2 nanotubes: influence of the cathodic pre-treatment, water aging, and thermal oxide |
author |
Silva, Diego D. |
author_facet |
Silva, Diego D. Sánchez-Montes, Isaac Hammer, Peter [UNESP] Aquino, José M. |
author_role |
author |
author2 |
Sánchez-Montes, Isaac Hammer, Peter [UNESP] Aquino, José M. |
author2_role |
author author author |
dc.contributor.none.fl_str_mv |
Universidade Federal de São Carlos (UFSCar) Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Silva, Diego D. Sánchez-Montes, Isaac Hammer, Peter [UNESP] Aquino, José M. |
dc.subject.por.fl_str_mv |
barrier oxide black TiO2 microwave oven oxygen vacancy supercapacitor TiO2 nanotubes |
topic |
barrier oxide black TiO2 microwave oven oxygen vacancy supercapacitor TiO2 nanotubes |
description |
The electrical and morphological properties as well as the assessment of self organized TiO2 nanotubes (TiO2-NTs) as supercapacitors were carried out for the first time for samples grown in organic medium and annealed in a microwave oven (MO) through a hybrid thermal heating. These samples were compared to those obtained by heat treatment in a conventional muffle furnace (MF). No significant differences were observed in the nanotubular morphology, crystalline structure (anatase phase) and of the band gap values; however, samples annealed in a MO showed an improvement in the donor density and a higher flat band potential. After a cathodic pre-treatment (–1.4 V vs. NHE for 60 s) to generate oxygen vacancies/Ti3+ (black TiO2) the MO annealed samples exhibited a superior areal capacitance than the MF annealed samples, even after 5000 cycles of galvanostatic charge-discharge experiments. The improved performance of the MO annealed samples is related to a higher amount of produced oxygen vacancies/Ti3+ on the surface of TiO2-NT. As the generated surface oxygen vacancies are unstable, reactions with adsorbed H2O lead to a more hydroxylated surface layer. Electrochemical impedance spectroscopy (EIS) measurements of the as-prepared black TiO2 exhibited a significant diminishment of the charge transfer resistance for the MO annealed samples; however, assessment of the water aging stability of these pre-treated films resulted in increasing values for the charge transfer resistance. The thermally grown oxide interface layer formed on the Ti substrate showed for both annealing methods similar EIS profiles and seems it has no influence on the values obtained for the areal capacitance. The results suggest that microwave annealing is an interesting option to convert amorphous TiO2-NTs into the crystalline anatase phase, especially because this procedure is very rapid and facile, resulting in an improvement of their areal capacitance after a cathodic pre-treatment. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-08-10 2018-12-11T17:12:11Z 2018-12-11T17:12:11Z |
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/10.1016/j.electacta.2017.05.112 Electrochimica Acta, v. 245, p. 165-172. 0013-4686 http://hdl.handle.net/11449/174633 10.1016/j.electacta.2017.05.112 2-s2.0-85019770039 2-s2.0-85019770039.pdf 6466841023506131 0000-0002-3823-0050 |
url |
http://dx.doi.org/10.1016/j.electacta.2017.05.112 http://hdl.handle.net/11449/174633 |
identifier_str_mv |
Electrochimica Acta, v. 245, p. 165-172. 0013-4686 10.1016/j.electacta.2017.05.112 2-s2.0-85019770039 2-s2.0-85019770039.pdf 6466841023506131 0000-0002-3823-0050 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Electrochimica Acta 1,439 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
165-172 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 |
|
_version_ |
1808129359143239680 |