Activities per year
Abstract
Circularly polarized luminescence (CPL) is of interest due to its wide potential application in semiconductors. To balance the emission efficiency and luminescence dissymmetry factor (gPL) of a CPL emitter, in this context, two chiral, phosphorescent and liquid-crystalline cyclometalated platinum complexes, abbreviated R-Pt and S-Pt, are prepared. The complexes, which show an intense green emission at 504 nm both in solution and in the solid state, contain a simple, ortho-metalated 2-phenylpyridine unit functionalized with a chiral 2-octanol chain, with liquid crystallinity being induced by modifying the β-diketonato ligand with mesogenic groups. Interestingly, both the chiral smectic (SmA*) and nematic (N*) phases are found by a combination of polarized optical microscopy, differential scanning calorimetry, and small-angle X-ray scattering. By annealing, distinct CPL emission is achieved in the solid state with a gPL around 0.02. Employing the chiral platinum complexes as the dopant, solution-processable organic light-emitting diodes present an external quantum efficiency of 11.3% and strong, circularly polarized electroluminescence with an extremely high luminescence dissymmetry value (gEL) of 0.06 after annealing at 100 °C. This work opens an avenue for designing CPL-active emitters with high emission efficiency and high dissymmetry factor.
Original language | English |
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Article number | 2000775 |
Journal | Advanced Optical Materials |
Volume | 8 |
Issue number | 20 |
Early online date | 19 Jul 2020 |
DOIs | |
Publication status | Published - 19 Oct 2020 |
Keywords
- chiral liquid crystals
- circularly polarized luminescence
- organic light-emitting diodes
- phosphorescence
- platinum complexes
Activities
- 1 Academic
Projects
- 1 Finished
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Design, Synthesis and Device Properties of Multifunctional, Phosphorescent Metallomesogens
Bruce, D. W. (Principal investigator)
1/03/19 → 30/03/22
Project: Research project (funded) › Research