Encapsulated Narrowband Emitters for Efficient and Stable Blue Hyperfluorescent OLEDs

Blue organic light-emitting diodes (OLEDs) remain the major bottleneck for next-generation displays, suffering from a critical trade-off between efficiency, stability, and color purity. Hyperfluorescence (HF), which combines thermally activated delayed fluorescence (TADF) hosts with narrowband emitters, offers a powerful approach. Yet, device performance is fundamentally limited by Dexter energy transfer (DET), which drives triplet exciton accumulation and material degradation. The ENBOLED project introduces a covalent encapsulation strategy for multi-resonance (MR)-TADF emitters to suppress DET, mitigate aggregation, and enhance photostability. In parallel, tailored TADF hosts will be developed to optimize energy transfer process and exciton confinement. Ultrafast spectroscopy will be employed to uncover mechanistic insights into energy transfer, providing structure–property guidelines for material and device design. By integrating advanced encapsulated emitters, delicately engineered hosts and spectroscopic insights, ENBOLED targets blue HF-OLEDs with external quantum efficiencies above 30% and operational lifetimes (LT95) beyond 500 h. ENBOLED will drive the commercialization of high-performance blue HF-OLEDs while advancing fundamental insights into molecular interactions, thereby pushing the frontiers of organic optoelectronics. By addressing the rapidly growing demand, the project will foster innovation in green optoelectronics and strengthen Europe's scientific and industrial competitiveness in the global OLED market. The applicant brings proven expertise in HF-OLED device physics and will acquire new skills in material synthesis and photophysical characterization within a world-leading host group, thereby strengthening his trajectory toward an independent research career.