Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5
The electrochemical behavior of caffeic acid (H3CAF) in aqueous solutions with pH 2.0 to 8.5 was studied by cyclic voltammetry, controlled potential electrolysis and UV-vis spectroscopy. The electro-oxidation of H3CAF involves a reversible transfer of two electrons and two protons in solutions of pH...
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| Format: | Article |
| Language: | English |
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Sociedade Brasileira de Química
2002-01-01
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| Series: | Journal of the Brazilian Chemical Society |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532002000300007 |
| _version_ | 1828527490165899264 |
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| author | Giacomelli Cristiano Ckless Karina Galato Dayani Miranda Fabio S. Spinelli Almir |
| author_facet | Giacomelli Cristiano Ckless Karina Galato Dayani Miranda Fabio S. Spinelli Almir |
| author_sort | Giacomelli Cristiano |
| collection | DOAJ |
| description | The electrochemical behavior of caffeic acid (H3CAF) in aqueous solutions with pH 2.0 to 8.5 was studied by cyclic voltammetry, controlled potential electrolysis and UV-vis spectroscopy. The electro-oxidation of H3CAF involves a reversible transfer of two electrons and two protons in solutions of pH up to 5.5, in agreement with the one step-two electron mechanism. In solutions of pH higher than 5.5, the process of electro-oxidation of H3CAF follows an ECi mechanism. The main oxidation product is the corresponding o-quinone (o-HCAF), which is decomposed quickly at pH higher than 7.4 obeying a first order kinetics. In the pH range investigated, the formal potential (E0') varies linearly with pH, generating a straight line with an angular coefficient of -60.83 mV/pH. In parallel, the anodic peak current (i pa) decreases in a nonlinear mode. The processes are controlled by diffusion over the whole pH range studied. |
| first_indexed | 2024-12-11T21:39:15Z |
| format | Article |
| id | doaj.art-6dffaa0bd5324a04afc72e11889a3edc |
| institution | Directory Open Access Journal |
| issn | 0103-5053 |
| language | English |
| last_indexed | 2024-12-11T21:39:15Z |
| publishDate | 2002-01-01 |
| publisher | Sociedade Brasileira de Química |
| record_format | Article |
| series | Journal of the Brazilian Chemical Society |
| spelling | doaj.art-6dffaa0bd5324a04afc72e11889a3edc2022-12-22T00:49:54ZengSociedade Brasileira de QuímicaJournal of the Brazilian Chemical Society0103-50532002-01-01133332338Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5Giacomelli CristianoCkless KarinaGalato DayaniMiranda Fabio S.Spinelli AlmirThe electrochemical behavior of caffeic acid (H3CAF) in aqueous solutions with pH 2.0 to 8.5 was studied by cyclic voltammetry, controlled potential electrolysis and UV-vis spectroscopy. The electro-oxidation of H3CAF involves a reversible transfer of two electrons and two protons in solutions of pH up to 5.5, in agreement with the one step-two electron mechanism. In solutions of pH higher than 5.5, the process of electro-oxidation of H3CAF follows an ECi mechanism. The main oxidation product is the corresponding o-quinone (o-HCAF), which is decomposed quickly at pH higher than 7.4 obeying a first order kinetics. In the pH range investigated, the formal potential (E0') varies linearly with pH, generating a straight line with an angular coefficient of -60.83 mV/pH. In parallel, the anodic peak current (i pa) decreases in a nonlinear mode. The processes are controlled by diffusion over the whole pH range studied.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532002000300007caffeic acidoxidationelectrochemistryUV-vis spectroscopy |
| spellingShingle | Giacomelli Cristiano Ckless Karina Galato Dayani Miranda Fabio S. Spinelli Almir Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 Journal of the Brazilian Chemical Society caffeic acid oxidation electrochemistry UV-vis spectroscopy |
| title | Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 |
| title_full | Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 |
| title_fullStr | Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 |
| title_full_unstemmed | Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 |
| title_short | Electrochemistry of Caffeic Acid Aqueous Solutions with pH 2.0 to 8.5 |
| title_sort | electrochemistry of caffeic acid aqueous solutions with ph 2 0 to 8 5 |
| topic | caffeic acid oxidation electrochemistry UV-vis spectroscopy |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532002000300007 |
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