Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7
The voltammetry induced growth of tin oxides on tin in the buffer solution of 0.18 mol L-1 Na2H2PO4 and 0.18 mol L-1 KH2PO4 (pH 8.7) has been studied. Ex-situ ellipsometric measurements were made in an order to determine thicknesses of the grown oxides. From these results the film volume per charge...
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International Association of Physical Chemists (IAPC)
2016-12-01
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| Series: | Journal of Electrochemical Science and Engineering |
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| Online Access: | http://pub.iapchem.org/ojs/index.php/JESE/article/view/326 |
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| author | Tiago Brandão Costa Tania Maria Cavalcanti Nogueira Ladário da Silva |
| author_facet | Tiago Brandão Costa Tania Maria Cavalcanti Nogueira Ladário da Silva |
| author_sort | Tiago Brandão Costa |
| collection | DOAJ |
| description | The voltammetry induced growth of tin oxides on tin in the buffer solution of 0.18 mol L-1 Na2H2PO4 and 0.18 mol L-1 KH2PO4 (pH 8.7) has been studied. Ex-situ ellipsometric measurements were made in an order to determine thicknesses of the grown oxides. From these results the film volume per charge unit, Vf, was calculated for different charge densities of the film. This parameter was used to calculate the variable ionic resistivity of the film, ρf, considered by the Ohmic model for the case of voltammetric growth of oxides on metals having a previously existing continuous film. Tin oxide films grown at 2 mV s-1 showed to be less dense for values of charge density below 50 C m-2, having Vf near
5.7x10-10 m3 C-1. For higher values of charge density, tin oxide films become denser, having Vf near 0.5x10-10 m3 C-1. The calculated values of the variable ionic resistivity of the film during voltammetric growth showed that ρf passes through a minimum (justifying the maximum in current densities). This behavior was also found by other authors in the cases of Zn, Nb, Ni and galvanized steel sheets. |
| first_indexed | 2024-12-18T06:27:25Z |
| format | Article |
| id | doaj.art-71cc7ae60ebc44968c727a6c53f13de3 |
| institution | Directory Open Access Journal |
| issn | 1847-9286 |
| language | English |
| last_indexed | 2024-12-18T06:27:25Z |
| publishDate | 2016-12-01 |
| publisher | International Association of Physical Chemists (IAPC) |
| record_format | Article |
| series | Journal of Electrochemical Science and Engineering |
| spelling | doaj.art-71cc7ae60ebc44968c727a6c53f13de32022-12-21T21:18:00ZengInternational Association of Physical Chemists (IAPC)Journal of Electrochemical Science and Engineering1847-92862016-12-016410.5599/jese.326233Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7Tiago Brandão Costa0Tania Maria Cavalcanti Nogueira1Ladário da Silva2Programa de Pós-Graduação em Engenharia Metalúrgica (PPGEM), Escola de Engenharia Industrial Metalúrgica de Volta Redonda (EEIMVR), Universidade Federal Fluminense (UFF), 27255-125 Volta Redonda, RJPrograma de Pós-Graduação em Engenharia Metalúrgica (PPGEM), Escola de Engenharia Industrial Metalúrgica de Volta Redonda (EEIMVR), Universidade Federal Fluminense (UFF), 27255-125 Volta Redonda, RJ and Departmento de Metalurgia, EEIMVR, UFF, 27255-125 Volta Redonda, RJPrograma de Pós-Graduação em Engenharia Metalúrgica (PPGEM), Escola de Engenharia Industrial Metalúrgica de Volta Redonda (EEIMVR), Universidade Federal Fluminense (UFF), 27255-125 Volta Redonda, RJ and Departmento de Física, Instituto de Ciências Exatas (ICEx), UFF, 27213-145 Volta Redonda, RJThe voltammetry induced growth of tin oxides on tin in the buffer solution of 0.18 mol L-1 Na2H2PO4 and 0.18 mol L-1 KH2PO4 (pH 8.7) has been studied. Ex-situ ellipsometric measurements were made in an order to determine thicknesses of the grown oxides. From these results the film volume per charge unit, Vf, was calculated for different charge densities of the film. This parameter was used to calculate the variable ionic resistivity of the film, ρf, considered by the Ohmic model for the case of voltammetric growth of oxides on metals having a previously existing continuous film. Tin oxide films grown at 2 mV s-1 showed to be less dense for values of charge density below 50 C m-2, having Vf near 5.7x10-10 m3 C-1. For higher values of charge density, tin oxide films become denser, having Vf near 0.5x10-10 m3 C-1. The calculated values of the variable ionic resistivity of the film during voltammetric growth showed that ρf passes through a minimum (justifying the maximum in current densities). This behavior was also found by other authors in the cases of Zn, Nb, Ni and galvanized steel sheets.http://pub.iapchem.org/ojs/index.php/JESE/article/view/326EllipsometryTin oxideOhmic modelVoltammetryVariable ionic resistivity |
| spellingShingle | Tiago Brandão Costa Tania Maria Cavalcanti Nogueira Ladário da Silva Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 Journal of Electrochemical Science and Engineering Ellipsometry Tin oxide Ohmic model Voltammetry Variable ionic resistivity |
| title | Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 |
| title_full | Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 |
| title_fullStr | Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 |
| title_full_unstemmed | Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 |
| title_short | Ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of pH 8.7 |
| title_sort | ellipsometric measurement of thickness of tin oxides grown by voltammetry in phosphate solution of ph 8 7 |
| topic | Ellipsometry Tin oxide Ohmic model Voltammetry Variable ionic resistivity |
| url | http://pub.iapchem.org/ojs/index.php/JESE/article/view/326 |
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