Fused Polycyclic Compound for OLED Emission Layer

The patent modifies molecular parameters of the organic compound by introducing a fused polycyclic core structure with specific substituents (R1-R13 groups) at defined positions (n1-n13). This changes the electronic and steric parameters of the molecule to reduce intermolecular interactions and Dexter energy transfer, thereby simultaneously improving emission efficiency and device lifespan

The invention creates a composite molecular structure combining a fused polycyclic core (such as dibenzofuran, dibenzothiophene, carbazole, or indole units) with various substituent groups. This composite structure achieves optimized photophysical properties by combining the stability of the fused core with the functional properties of the substituents, resolving the contradiction between efficiency and lifespan

The patent introduces bulky substituent groups (such as tert-butyl, phenyl, or heteroaryl groups) at specific local positions (R1-R13) of the molecular structure. These local modifications create steric hindrance that prevents close intermolecular contact and reduces Dexter energy transfer, while the overall molecular structure remains compatible with standard fabrication processes

The fused polycyclic core structure acts as an intermediary framework that separates the electron-rich and electron-poor regions of the molecule. This spatial separation mediates the reduction of intermolecular interactions and Dexter energy transfer, improving device performance without complicating the manufacturing process