Purely Organic TADF Emitters for OLED Efficiency and Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optoelectronic devices, such as OLEDs, face challenges in achieving high efficiency and stability while maintaining comparable color emission.
Innovation Solution
Development of new purely organic molecules with emission maxima in the blue, sky-blue, or green spectral range, exhibiting thermally activated delayed fluorescence (TADF) and photoluminescence quantum yields of 20% or more.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If metal complexes are used as emitter materials in OLEDs, then device efficiency can be improved, but device stability and purity of organic material decrease
Solution Approach 1:
The patent extracts and eliminates metal ions from the emitter material composition, using purely organic molecules (formulas I, II, and III) as emitter materials in OLEDs. This extraction of metal components resolves the contradiction by maintaining high efficiency through organic TADF emitters while improving stability and purity by removing metal-related degradation pathways.
Solution Approach 2:
The patent changes the fundamental parameter of emitter material composition from metal-based complexes to purely organic molecules with specific TADF properties. This parameter change enables achieving both high efficiency through optimized organic emitters and improved stability through the inherent chemical stability of organic-only compositions, resolving the trade-off between efficiency and stability.
2Use of energy by moving object
If conventional emitter materials are used, then device operation is achieved, but photoluminescence quantum yields and emission efficiency are limited
Solution Approach 1:
The patent changes the photophysical parameters of the emitter materials by introducing TADF (thermally activated delayed fluorescence) mechanisms with specific lifetime characteristics (10-1000 μs) and quantum yields (20-80%). This parameter optimization resolves the contradiction by achieving high photoluminescence quantum yields through TADF while maintaining high emission efficiency through optimized molecular structures (formulas I, II, III) and device architecture.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The use of these organic molecules in optoelectronic devices leads to higher efficiencies and stability compared to known emitter materials, with improved photoluminescence quantum yields and emission characteristics.
Implementation Method 1
The organic molecules exhibit in particular thermally activated delayed fluorescence (TADF). The photoluminescence quantum yields of the organic molecules according to the invention are, in particular, 20% or more.
Data Source
Figure 1
AI summary
The invention relates to an organic compound, in particular for the use in optoelectronic devices. According to the invention, the organic compound has - two first identical chemical moieties with a structure of Formula (I), and - four second chemical moieties with a structure of Formula (II), and - one third chemical moiety RA with a structure of Formula Py, wherein the two first chemical moieties are linked to each other via the chemical moiety RA, wherein each dotted bond in Formula Py indicates the binding site of RA to one of the two identical first chemical moieties comprising or consisting of a structure of Formula (I).