Influence of energy gap between charge-transfer and locally excited states on organic long persistence luminescence
| Autor: | Kai Wang, Ryota Kabe, Chihaya Adachi, Zesen Lin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Band gap Photochemistry Exciton Chemical physics Science Optical spectroscopy General Physics and Astronomy 02 engineering and technology 010402 general chemistry Excimer 01 natural sciences General Biochemistry Genetics and Molecular Biology Article Singlet state lcsh:Science Multidisciplinary General Chemistry 021001 nanoscience & nanotechnology Fluorescence 0104 chemical sciences Excited state lcsh:Q 0210 nano-technology Luminescence Phosphorescence |
| Zdroj: | Nature Communications, Vol 11, Iss 1, Pp 1-7 (2020) Nature Communications |
| ISSN: | 2041-1723 |
| Popis: | Organic long-persistent luminescence (LPL) is an organic luminescence system that slowly releases stored exciton energy as light. Organic LPL materials have several advantages over inorganic LPL materials in terms of functionality, flexibility, transparency, and solution-processability. However, the molecular selection strategies for the organic LPL system still remain unclear. Here we report that the energy gap between the lowest localized triplet excited state and the lowest singlet charge-transfer excited state in the exciplex system significantly controls the LPL performance. Changes in the LPL duration and spectra properties are systematically investigated for three donor materials having a different energy gap. When the energy level of the lowest localized triplet excited state is much lower than that of the charge-transfer excited state, the system exhibits a short LPL duration and clear two distinct emission features originating from exciplex fluorescence and donor phosphorescence. Long-persistent luminescence can be realized in all-organic systems (OLPL) but still with unsatisfactory performance. Here the authors investigate the relationships between energy levels and emission properties in a series of OLPL materials and propose a design strategy for efficient OLPL performance. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|