High-performance Deep Blue “Hot Exciton” Materials Based on Anthracene

Abstract

： The blue OLED material plays a vital role in the field of electroluminescence. Based on high - energy ex⁃ cited state transition ， the “ hot exciton ” materials show the potential of excellent blue light emitting. We designed and synthesized a novel D - π - A structure molecule TACN using anthracene as the core building unit ， triphenylben⁃ zene as the weak donor and phenylcyanogen as the acceptor by adjusting the ability of pushing and pulling electrons. Distorted triphenylbenzene provides a highly distorted molecular conformation ， which effectively attenuates the quenching effect in the aggregated state. Therefore ， TACN exhibits a high fluorescence quantum yield （ 47% in the aggregated state ） . The experimental results and theoretical analysis show that TACN has the “ hot exciton ” character⁃ istic ， and its large T 2 - T 1 gap （ 1. 45 eV ） effectively hinders the internal conversion （ IC ） process from T 2 to T 1 ， while its small T 2 - S 1 energy difference （ 0. 18 eV ， T 2 > S 1 ） facilitates the reverse intersystem crossing （ RISC ） process. Non - doped devices based on TACN exhibit dark blue emission （ λ max