Construction of Weakly Hybridized Excited State Using Donor‐π‐Acceptor Structure and Applications: From Highly Efficient Pure‐Blue Electro‐Fluorescence to Visible‐Light Polymerization

Abstract Herein this work, a novel donor‐π‐acceptor (D‐π‐A) pure‐blue hybrid local and charge‐transfer (HLCT) fluorescent material TDFBO and its functionalization as organic light emitting diode (OLED) emitter and photoinitiator (PI) in photopolymerization is reported. The weak‐hybridization property involved by the fluorene π‐bridge can simultaneously give satisfied photo‐luminescent quantum yield (PLQY) and make efficient “hot‐exciton” channel achievable. Moreover, the D‐π‐A structure can also promote an exceeding electron mobility as high as 3.57×10 −4 cm 2 V −1 s −1 . Finally, it is noted that the TDFBO‐doped OLED can be regarded as the best one among the pure‐blue emissive OLEDs, which exhibits a high maximum external quantum efficiency of 11.1%, while the rolling‐off only stands on a low level, as 6% at 100 cd m −2 . Additionally, a relatively high final conversion of C = C double bond in a representative acrylate monomer is also attained by photoinitiation of TDFBO under 405 nm LED, where the photopolymerization has been applied to 3D printing.