The synthesis, photoluminescence and electroluminescence properties of a new emitter based on diphenylethene, carbazole and 9,9,10,10-tetraoxidethianthrene

Luminescent materials with aggregation-induced emission (AIE) property have privileged solid state emission by restriction of aggregation-caused quenching (ACQ) effect and thermally activated delayed fluorescence (TADF) materials can fully harvest singlet and triplet excitons to achieve efficient electroluminescence (EL). An excellent strategy is to combine AIE and TADF features to create an admirable new luminescent material. Herein, a new tailor-made material(DPECTT) is developed based on diphenylethene as skeleton, carbazole as donor group and 9, 9, 10, 10-tetraoxidethianthrene as accept group. Its structure is fully characterized by elemental analysis, NMR spectroscopy and mass spectrometry. Thermal, photophysical and electrochemical properties are investigated systematically. The results show that the aggregation-induced delayed fluorescence (AIE-TADF) compound exhibits good thermal stability, electrochemical stability and AIE and TADF properties. Ultimately, the non-doped OLED (Device A) was fabricated based on DPECTT as light-emitting layer. Device A showed bluish green light with a turn-on voltage of 5 V, a maximum brightness of 8264 cd m−2 and a maximum current efficiency of 3.96 cd A−1. These results fully demonstrate the utility of combining AIE and TADF to explore new high-efficiency emitters.