Molecular Suppression of the Pimerization of Viologens (=4,4′-Bipyridinium Derivatives) Attached to Nanocrystalline Titanium Dioxide Thin-Film Electrodes
| Autor: | Michael Felderhoff, Ngongo Molisho, Simona Webersinn, Lorenz Walder, Susanne Heinen |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Chemistry
Nanocrystalline titanium dioxide Radical Organic Chemistry Viologen Photochemistry Biochemistry Phosphonate Catalysis Inorganic Chemistry Absorbance chemistry.chemical_compound Electrochromism Drug Discovery Electrode medicine Physical and Theoretical Chemistry Layer (electronics) medicine.drug |
| Zdroj: | Helvetica Chimica Acta. 83:181-192 |
| ISSN: | 1522-2675 0018-019X |
| DOI: | 10.1002/(sici)1522-2675(20000119)83:1<181::aid-hlca181>3.0.co;2-u |
| Popis: | Twelve viologens, i.e., 4,4′-bipyridinium derivatives 1 – 12, were examined for their use as electrochromic material when attached to nanocrystalline titanium dioxide thin-film electrodes. Eight of these (1 – 4, 7 – 8, 10, and 12) are new, and their synthesis is included. The modifier compounds consist of one to four bipyridinium subunits with linear or dendritic architecture, equipped with one to three TiO2-anchoring phosphonate groups. They are tailored for high electrochromic dynamics (large absorbance change upon reduction) and low extent of pimerization (=charge-transfer (CT) complexation of viologen cation radicals). A new graphical method is presented for the discrimination of simple dilution phenomena and more complex structural effects on the extent of pimerization in the surface-attached viologen layer. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text