Iridium OLED Emitter Complexes for Efficiency and Lifetime
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing OLEDs face challenges in achieving high efficiency and longevity due to limitations in phosphorescent emitters, particularly in terms of device performance and stability.
Innovation Solution
The use of iridium complexes with three different bidentate ligands enhances the efficiency and lifetime of OLEDs by improving the performance of phosphorescent emitters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional phosphorescent emitters are used in OLEDs, then the device structure is simpler, but the device efficiency and lifetime are limited
Solution Approach 1:
The patent changes the chemical parameters of the phosphorescent emitter by using iridium complexes with three different bidentate ligands (LA, LB, LC) where each ligand has specific structural features (rings A, B, C, D being 5 or 6-membered carbocyclic or heterocyclic rings). This parameter change in molecular structure leads to improved device lifetime while managing the complexity through systematic ligand design
Solution Approach 2:
The patent employs composite material strategy by creating iridium complexes composed of multiple different bidentate ligands coordinated to the central iridium atom. This composite approach (Ir(LA)(LB)(LC) where LA, LB, and LC are different ligands) enhances the phosphorescent properties and device reliability compared to simpler single-ligand complexes
2Productivity
If conventional phosphorescent emitters are used in OLEDs, then the material synthesis is simpler, but the device efficiency is lower
Solution Approach 1:
The patent improves device efficiency by changing the chemical parameters of the emitter to iridium complexes with three different bidentate ligands featuring specific ring structures (5 or 6-membered carbocyclic or heterocyclic rings). This parameter optimization enhances photoluminescence quantum yield and electrophosphorescence efficiency, achieving higher productivity despite increased synthesis complexity
3Stability of the object's composition
If conventional phosphorescent emitters are used in OLEDs, then the device stability is lower, but the emitter structure is less complex
Solution Approach 1:
The patent enhances device stability by changing the structural parameters of the phosphorescent emitter to iridium complexes with three different bidentate ligands where each ligand contains stable 5 or 6-membered carbocyclic or heterocyclic rings. This structural parameter optimization improves molecular stability and device operational stability while managing complexity through systematic ligand selection
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 iridium complexes with three different bidentate ligands lead to improved device efficiency and stability, addressing the limitations of conventional phosphorescent emitters.
Implementation Method 1
The present disclosure relates to compounds for use as phosphorescent emitters, and devices, such as organic light emitting diodes, including the same. More specifically, this disclosure relates to iridium complexes comprising three different bidentate ligands and their use in OLEDs to enhance the device efficiency and lifetime.
Data Source
AI summary
Iridium complexes comprising three different bidentate ligands and their use in OLEDs to enhance the device efficiency and lifetime are disclosed. The complexes have a structure of the formula Ir(LA)(LB)(LC), where ligand LA is selected from a variety of structures, ligand LB has the structureand LC has the structureIn these structures rings A, B, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring; R1, R2, R3, RA, RB, RC, and RD can be any of a variety of substituents, and Z1 and Z2 are each independently C or N.