Related Experiment Video
Updated: Jul 23, 2025
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
9.8K
Constructing Highly Efficient Circularly Polarized Multiple-Resonance Thermally Activated Delayed Fluorescence
Qingyang Wang1,2, Li Yuan3, Cheng Qu1
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|July 18, 2023
Summary
This study introduces novel circularly polarized multiple-resonance thermally activated delayed fluorescence (CP-MR-TADF) materials for advanced displays. These materials achieve high efficiency and pure green emission in circularly polarized organic light-emitting diodes (CP-OLEDs).
Area of Science:
- Organic electronics
- Materials science
- Photophysics
Background:
- Circularly polarized luminescence (CPL) and thermally activated delayed fluorescence (TADF) are crucial for high-performance organic light-emitting diodes (OLEDs).
- Existing materials often struggle to combine CPL, narrowband emission, and TADF characteristics efficiently.
- There is a market demand for advanced displays with high color purity, ultrahigh definition, and 3D capabilities.
Purpose of the Study:
- To develop novel circularly polarized multiple-resonance thermally activated delayed fluorescence (CP-MR-TADF) materials.
- To engineer high-performance CP-MR-TADF enantiomers using an edge-topology molecular-engineering (ETME) strategy.
- To fabricate and optimize circularly polarized organic light-emitting diodes (CP-OLEDs) for display applications.
Main Methods:
- Utilized an edge-topology molecular-engineering (ETME) strategy to design CP-MR-TADF molecules.
- Synthesized a pair of enantiomers, (P and M)-BN-Py, integrating helical chirality into the multiple-resonance (MR) framework.
- Fabricated CP-OLEDs using the developed emitters and an ambipolar transport host (PhCbBCz).
Main Results:
- Achieved pure green emission with a sharp peak at 532 nm, FWHM of 37 nm, and CIE coordinates of (0.29, 0.68).
- Demonstrated high maximum external quantum efficiencies (EQEs) of 30.6% for (P)-BN-Py and 29.2% for (M)-BN-Py.
- Observed clear circularly polarized electroluminescence (CPEL) signals with electroluminescence dissymmetry factors (gEL) of -4.37 × 10-4 and +4.35 × 10-4.
Conclusions:
- The developed (P and M)-BN-Py enantiomers represent high-performance CP-MR-TADF materials.
- These materials are suitable for fabricating efficient CP-OLEDs with high color purity.
- The findings address the demand for advanced displays, particularly ultrahigh-definition and 3D applications.
Keywords:
circularly polarized luminescencemultiple resonancenarrowband emissionorganic light-emitting diodesthermally activated delayed fluorescenceMore Related Videos
Related Concept Videos
02:25Molecules with Multiple Chiral Centers
11.8K
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
11.8K
01:17Thermal Electrocyclic Reactions: Stereochemistry
2.0K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
2.0K
02:30Chirality in Nature
13.5K
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.
13.5K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.9K
02:05Prochirality
3.8K
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
3.8K
02:33Stereoisomerism of Cyclic Compounds
9.0K
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
9.0K