摘要
Stable organic luminescent radicals are a special class of compounds integrating optical,electrical,and magnetic properties.Luminescent radicals not only have potential applications in the field of the organic light-emitting diodes(OLEDs)but can also be applied in the fields of fluorescence sensing,bioimaging,and so forth.Nevertheless,due to the adverse effects of solvent polarity on the luminescent performance of radicals,no feasible approaches have been found in the literature toward fluorescent sensing.In this work,we report two luminescent radicals,2αPyID-TTM and 2δPyID-TTM,whose emissions show high efficiency and less dependence on solvent polarity.Both radicals show remarkable protonation–deprotonation properties.Besides,2αPyID-TTM exhibits significant fluorescence quenching and colorimetric response toward Fe^(3+)in aqueous solution.This suggests the possibility of a fluorometric/colorimetric dual-channel probe for Fe^(3+).Moreover,an optimized OLED using 2δPyID-TTM as an emissive dopant shows pure red emission and a maximum external quantum efficiency(EQE)of 10.6%.These results show promise for luminescent radicals as fluorescent probes and electroluminescent emitters.
基金
This research was made possible by a generous grant from the National Natural Science Foundation of China(grant nos.51925303,21875083,and 91833304)
the China Postdoctoral Science Foundation(grant nos.2020TQ0117 and 2020M681033)
the program“JLUSTIRT”(grant no.2019TD-33).
