Covalent Modification of Glassy Carbon Surfaces by Electrochemical Grafting of Aryl Iodides
The reduction of an aryl iodide is generally believed to involve a clean-cut two-electron reduction to produce an aryl anion and iodide. This is in contradiction to what is observed if a highly efficient grafting agent, such as an aryldiazonium salt, is employed. The difference in behavior is explai...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1985. - 33(2017), 13 vom: 04. Apr., Seite 3217-3222 |
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| Weitere Verfasser: | , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2017
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't |
| Zusammenfassung: | The reduction of an aryl iodide is generally believed to involve a clean-cut two-electron reduction to produce an aryl anion and iodide. This is in contradiction to what is observed if a highly efficient grafting agent, such as an aryldiazonium salt, is employed. The difference in behavior is explained by the much more extreme potentials required for reducing an aryl iodide, which facilitates the further reduction of the aryl radical formed as an intermediate. However, in this study we disclose that electrografting of aryl iodides is indeed possible upon extended voltammetric cycling. This implies that even if the number of aryl radicals left unreduced at the electrode surface is exceedingly small, a functionalization of the surface may still be promoted. In fact, the grafting efficiency is found to increase during the grafting process, which may be explained by the inhibiting effect the growing film exerts on the competing reduction of the aryl radical. The slow buildup of the organic film results in a well-ordered structure as shown by the well-defined electrochemical response from a grafted film containing ferrocenylmethyl groups. Hence, the reduction of aryl iodides allows a precisely controlled, albeit slow, growth of thin organic films |
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| Beschreibung: | Date Completed 15.05.2018 Date Revised 15.05.2018 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.7b00300 |