AIE-active 9,10-bis(alkylarylvinyl)anthracences with pendent diethoxylphosphorylmethyl groups as solution-processable efficient EL luminophores

Abstract

Solution-processable organic small molecules exhibiting the aggregation-induced emission (AIE) feature as electroluminescent (EL) emitters are very desirable because they can combine the low-cost solution processability of polymers, the reproducible well-defined structures of small molecules, and the strong solid-state fluorescence of AIE molecules; however, they are rarely reported. Herein, we first investigated the thermal stability, optical properties, stimuli-responsive behaviors, and application in solution-processed EL device of 2,6-bis(diethoxylphosphorylmethyl)-9,10-bis(N-alkylcarbazol-3-yl-vinyl)-anthracence (PAC8). PAC8 exhibited AIE behaviour, reversible mechanochromic luminescence, good thermal stability and strong crystalline green emission. More interestingly, PAC8 solution could be spin-coated into a good quality film, and the solution-processed non-doped EL device emitted 596 nm of orange-red light with peak luminous efficiencies (9.4 cd A⁻¹ and 3.9 lm W⁻¹) and external quantum efficiency up to 3.9%. This impressive EL performance signified that the pendent diethoxylphosphorylmethyl groups could be used as a promising avenue for improving the film-formation and EL performance.