Synthesis, Photophysical Properties, and Device Application of Internal BN-Fused Fluoranthenes

Existing BN-doped fluoranthenes are typically peripheral dopants with blue-shifted emission and loose intermolecular interactions. Herein, we strategically engineer internal BN doping in symmetric fluoranthene analogues that induces a pronounced red-shift in emission and directional B···π/B···B interactions. This molecular design enables enhanced orbital overlap through tight π-π stacking, yielding an outstanding hole mobility of 0.8 cm² V^-1 s^-1 in organic field-effect transistors. This work culminates in the first successful application of BN-doped fluoranthene.