Donor-Acceptor Type Pendant Conjugated Molecules Based on a Triazine Center with Depressed Intramolecular Charge Transfer Characteristics as Gain Media for Organic Semiconductor Lasers
- 9 March 2020
- journal article
- research article
- Published by Wiley in Chemistry – A European Journal
- Vol. 26 (14), 3103-3112
- https://doi.org/10.1002/chem.201904548
Abstract
A set of fluorene-capped pendant conjugated molecules (T-m and T-p), which consist of a triazine center with three carbazole substituents as the donor-acceptor (D-A) type pendant structure, were designed, synthesized, and investigated as gain media for organic semiconductor lasers (OSLs). In particular, varying the capping positions of the fluorene units on the pendant core structures results in significantly different intramolecular charge transfer (ICT) properties, where T-m manifested depressed ICT characteristic and high fluorescence quantum yield. The lowest amplified spontaneous emission (ASE) threshold in neat films was recorded as 1.9 mu J cm(-2) for T-m and 83.8 mu J cm(-2) for T-p, which indicated that the depressed ICT characteristics in the case of T-m help to enhance the ASE properties. Remarkably, the ASE threshold remained almost unchanged and the ASE spectra showed very small shifts (within 1 nm) for T-m with film samples annealed up to 180 degrees C in open air. In contrast, its linear counterpart 2FEtCz-m showed a clearly increased ASE threshold upon annealing above 100 degrees C. The results suggest that the selective construction of conjugated pendant molecules with depressed ICT characteristics is beneficial for finely modulating the optical and electrical properties as well as improving the thermostability and photostability, which manifests the great potential as a robust gain media for OSLs.Keywords
Funding Information
- National Natural Science Foundation of China (21835003, 91833304, 21422402, 21674050, 21604043, 20904024)
- National Basic Research Program of China (2014CB648300, 2017YFB0404501)
- Natural Science Foundation of Jiangsu Province (BE2019120, BK20160888)
This publication has 35 references indexed in Scilit:
- Highly Unidirectional Emission and Ultralow‐Threshold Lasing from On‐Chip Ultrahigh‐Q MicrocavitiesAdvanced Materials, 2012
- A High Gain and High Charge Carrier Mobility Indenofluorene‐Phenanthrene Copolymer for Light Amplification and Organic LasingAdvanced Materials, 2010
- Synthesis and Characterization of Thiophene-Containing Naphthalene Diimide n-Type Copolymers for OFET ApplicationsMacromolecules, 2010
- Enhanced Solid‐State Luminescence and Low‐Threshold Lasing from Starburst Macromolecular MaterialsAdvanced Materials, 2009
- Kinked Star‐Shaped Fluorene/ Triazatruxene Co‐oligomer Hybrids with Enhanced Functional Properties for High‐Performance, Solution‐Processed, Blue Organic Light‐Emitting DiodesAdvanced Functional Materials, 2007
- Photophysical Properties of a Series of Poly(ladder‐type phenylene)sAdvanced Functional Materials, 2007
- Fast Intramolecular Charge Transfer with a Planar Rigidized Electron Donor/Acceptor MoleculeJournal of the American Chemical Society, 2004
- High-Efficiency Organic Electrophosphorescent Diodes Using 1,3,5-Triazine Electron Transport MaterialsChemistry of Materials, 2004
- A Novel Class of Emitting Amorphous Molecular Materials as Bipolar Radical Formants: 2-{4-[Bis(4-methylphenyl)amino]phenyl}- 5-(dimesitylboryl)thiophene and 2-{4-[Bis(9,9-dimethylfluorenyl)amino]phenyl}- 5-(dimesitylboryl)thiopheneJournal of the American Chemical Society, 2000
- Intramolecular Charge Transfer Excited State Relaxation Processes in Para-Substituted N,N-Dimethylaniline: A Theoretical Study Including Solvent EffectsThe Journal of Physical Chemistry, 1995