Helicene-based emitters with unique inherent circularly polarized luminescence(CPL)are promising yet remain a formidable challenge for highly efficient circularly polarized organic light-emitting diodes(CP-OLEDs),ascr...Helicene-based emitters with unique inherent circularly polarized luminescence(CPL)are promising yet remain a formidable challenge for highly efficient circularly polarized organic light-emitting diodes(CP-OLEDs),ascribed to their tough synthesis,low emission efficiency,and easy racemization in the thermal deposition process.Herein,a pair of helicenebased enantiomers,namely(P)-helicene-BN and(M)-helicene-BN,were developed,which merge helical chirality and the B/N/S inserted polycyclic aromatic framework to concurrently feature CPL and narrow thermally activated delayed fluorescence(TADF)characteristics.Benefiting from the excellent thermal/photophysical/chiroptical properties,the narrowband green CP-OLEDs based on enantiomers achieved maximum external quantum efficiencies(EQE_(max))of up to 31.5%,and dissymmetry factor(|g_(EL)|)of 2.2×10^(−3).This work reveals the great potential of helicene-based emitters in CP-OLEDs.展开更多
基金This work was supported by the National Natural Science Foundation of China(grant nos.52130308,51903160,and 52022071)Shenzhen Science and Technology Program(grant no.KQTD20170330110107046)the Shenzhen Technology and Innovation Commission(grant no.JCYJ20180507182244027).
文摘Helicene-based emitters with unique inherent circularly polarized luminescence(CPL)are promising yet remain a formidable challenge for highly efficient circularly polarized organic light-emitting diodes(CP-OLEDs),ascribed to their tough synthesis,low emission efficiency,and easy racemization in the thermal deposition process.Herein,a pair of helicenebased enantiomers,namely(P)-helicene-BN and(M)-helicene-BN,were developed,which merge helical chirality and the B/N/S inserted polycyclic aromatic framework to concurrently feature CPL and narrow thermally activated delayed fluorescence(TADF)characteristics.Benefiting from the excellent thermal/photophysical/chiroptical properties,the narrowband green CP-OLEDs based on enantiomers achieved maximum external quantum efficiencies(EQE_(max))of up to 31.5%,and dissymmetry factor(|g_(EL)|)of 2.2×10^(−3).This work reveals the great potential of helicene-based emitters in CP-OLEDs.