Chiral TADF Polymers Realizing Highly-Efficient Deep-Red Circularly Polarized Electroluminescence Over 660 nm

摘要

Circularly polarized electroluminescence (CPEL) from thermally activateddelayed fluorescence (TADF) emitters have been widely reported in recentyears. However, a universal strategy for designing deep-red chiral TADFemitters is still unexplored. Herein, to address the problem, a pair of chiraldonor intermediates are designed and synthesized for preparing deep-redchiral TADF emitters, and two novel chiral TADF polymers R-P and S-P aredeveloped through this strategy. The polymers exhibit intense mirror-imagecircularly polarized luminescence (CPL) signals in toluene dilute solution.Besides, a series of solution-processed circularly polarized polymerlight-emitting diode (CP-PLED) devices are fabricated with R-P and S-P. Thecorresponding devices achieve persuasive performance with externalquantum efficiencies (EQEs) of 6.2 and 5.8 at the wavelength of 662 nm,respectively. Besides, mirror-image CPEL signals are detected withelectroluminescence dissymmetry factors (gEL) of +1.6 × 10~（?3） and ?1.7 ×10~（?3） from the corresponding CP-PLED devices, respectively.