Abstract
The photoluminescence (PL) characteristics of merocyanine dye molecules in ionic liquids of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF 4) with different purity grades were investigated. The absorption spectra for this dye in all the ionic liquid solvents investigated looked very similar while the PL emission spectra differed markedly depending on the type of ionic liquid and the impurity content. In all purity grades of [BMIM]BF 4 and the ultrahigh grade of [BMIM]PF 6, the PL spectra of these merocyanine solutions showed a single peak around 480 nm. However, when a lower grade of [BMIM]PF 6 was used as the solvent, an additional PL peak appeared around 575 nm. The deprotonation from the hydroxyl group of the merocyanine molecule after photoexcitation is proposed to explain the phenomenon in this unique solvent system.
| Original language | English |
|---|---|
| Pages (from-to) | 1476-1480 |
| Number of pages | 5 |
| Journal | Journal of the Korean Physical Society |
| Volume | 48 |
| Issue number | 6 |
| Publication status | Published - Jun 2006 |
Keywords
- Ionic liquids
- Merocyanine
- Solvatochromism