Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions
Autor(a) principal: | |
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Data de Publicação: | 1997 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Journal of the Brazilian Chemical Society (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000600008 |
Resumo: | The electrical and semiconducting properties of thin anodic passive films potentiostatically formed (1 V £ Ef £ 5 V vs. sce) on polycrystalline niobium electrodes in aqueous 0.5 mol/L H3PO4 solutions (pH 1.3) were studied, at room temperature, using electrochemical impedance spectroscopy. The data were analysed with a transfer function using a non-linear fitting routine, assuming that the resistance of the film is coupled in series with the faradaic impedance of the Nb(0) Nb(V) reaction, and these in parallel with the capacitance of the passive film/electrolyte interface. The relative permittivity of the films was estimated as about 44. The number concentration of donors (N D) in the films was found to decrease with Ef (i.e., with increasing film thickness). A flat band potential value of -0.72 V was also obtained from Mott-Schottky plots. |
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Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutionsniobiumanodic oxidesemiconducting propertiespotentiostatic growthimpedance spectroscopyThe electrical and semiconducting properties of thin anodic passive films potentiostatically formed (1 V £ Ef £ 5 V vs. sce) on polycrystalline niobium electrodes in aqueous 0.5 mol/L H3PO4 solutions (pH 1.3) were studied, at room temperature, using electrochemical impedance spectroscopy. The data were analysed with a transfer function using a non-linear fitting routine, assuming that the resistance of the film is coupled in series with the faradaic impedance of the Nb(0) Nb(V) reaction, and these in parallel with the capacitance of the passive film/electrolyte interface. The relative permittivity of the films was estimated as about 44. The number concentration of donors (N D) in the films was found to decrease with Ef (i.e., with increasing film thickness). A flat band potential value of -0.72 V was also obtained from Mott-Schottky plots.Sociedade Brasileira de Química1997-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000600008Journal of the Brazilian Chemical Society v.8 n.6 1997reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50531997000600008info:eu-repo/semantics/openAccessBiaggio,Sonia R.Bocchi,NerilsoRocha-Filho,Romeu C.Varela,Francisco E.eng2010-07-23T00:00:00Zoai:scielo:S0103-50531997000600008Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2010-07-23T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
title |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
spellingShingle |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions Biaggio,Sonia R. niobium anodic oxide semiconducting properties potentiostatic growth impedance spectroscopy |
title_short |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
title_full |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
title_fullStr |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
title_full_unstemmed |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
title_sort |
Electrochemical characterization of thin passive films on Nb electrodes in H3PO4 solutions |
author |
Biaggio,Sonia R. |
author_facet |
Biaggio,Sonia R. Bocchi,Nerilso Rocha-Filho,Romeu C. Varela,Francisco E. |
author_role |
author |
author2 |
Bocchi,Nerilso Rocha-Filho,Romeu C. Varela,Francisco E. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Biaggio,Sonia R. Bocchi,Nerilso Rocha-Filho,Romeu C. Varela,Francisco E. |
dc.subject.por.fl_str_mv |
niobium anodic oxide semiconducting properties potentiostatic growth impedance spectroscopy |
topic |
niobium anodic oxide semiconducting properties potentiostatic growth impedance spectroscopy |
description |
The electrical and semiconducting properties of thin anodic passive films potentiostatically formed (1 V £ Ef £ 5 V vs. sce) on polycrystalline niobium electrodes in aqueous 0.5 mol/L H3PO4 solutions (pH 1.3) were studied, at room temperature, using electrochemical impedance spectroscopy. The data were analysed with a transfer function using a non-linear fitting routine, assuming that the resistance of the film is coupled in series with the faradaic impedance of the Nb(0) Nb(V) reaction, and these in parallel with the capacitance of the passive film/electrolyte interface. The relative permittivity of the films was estimated as about 44. The number concentration of donors (N D) in the films was found to decrease with Ef (i.e., with increasing film thickness). A flat band potential value of -0.72 V was also obtained from Mott-Schottky plots. |
publishDate |
1997 |
dc.date.none.fl_str_mv |
1997-01-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000600008 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000600008 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-50531997000600008 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Journal of the Brazilian Chemical Society v.8 n.6 1997 reponame:Journal of the Brazilian Chemical Society (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Journal of the Brazilian Chemical Society (Online) |
collection |
Journal of the Brazilian Chemical Society (Online) |
repository.name.fl_str_mv |
Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
||office@jbcs.sbq.org.br |
_version_ |
1750318163090735104 |