The realization of a BT.2020 blue emitter is challenging due to the spectral redshift associated with π-extension. Here, the authors report a multi-resonance thermally activated delayed fluorescence emitter, exhibiting ultrapure deep-blue narrow emission and CIEy ≤ 0.05 exceeding 20% efficiency.
- Junki Ochi
- Yuki Yamasaki
- Takuji Hatakeyama