Peripherally fused spiro structures enable the development of narrowband TADF emitters for highly efficient blue OLEDs.

ABSTRACT: To address the spectral broadening and red shift inherent in multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters, which are caused by aggregation due to their planar structures, we propose a strategic fusion of spiro groups at specific peripheral positions within the classic narrowband emitter DABNA core. Leveraging positional isomerism, this innovative approach enables the development of two blue TADF emitters: SFX-2BN (O-π-B) and SFX-3BN (O-π-N). The relative positioning of the electron-withdrawing boron (B) and electron-donating nitrogen (N) atoms around the oxygen enables precise emission tuning from sky-blue to pure blue. The rigid spiro structure acts as an intramolecular lock, effectively suppressing detrimental vibrations and π-π stacking, thereby yielding e

SUBMITTER: Li D 

PROVIDER: S-EPMC12421321 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature