Abstract

A new class of C^C^N ligand-containing carbazolylgold(III) dendrimers has been designed and synthesized. High photoluminescence quantum yields of up to 82 % in solid-state thin films and large radiative decay rate constants in the order of 105 s–1 are observed. These gold(III) dendrimers are found to exhibit thermally activated delayed fluorescence (TADF), as supported by variable-temperature emission spectroscopy, time-resolved photoluminescence decay and computational studies. Solution-processed organic light-emitting devices (OLEDs) based on these gold(III) dendrimers have been fabricated, which exhibit a maximum current efficiency of 52.6 cd A–1, maximum external quantum efficiency of 15.8 % and high power efficiency of 41.3 lm W–1. The operational stability of these OLEDs has also been recorded, with the devices based on zero- and second-generation dendrimers showing maximum half-lifetimes of 1,305 and 322 h at 100 cd m–2, respectively, representing the first demonstration of operationally stable solution-processed OLEDs based on gold(III) dendrimers.

Reference 

Li, L.-K.; Kwok, W.-K.; Tang, M.-C.; Cheung, W.-L.; Lai, S.-L.; Ng, M.; Chan, M.-Y.; Yam, V. W.-W., Chem. Sci. 2021, 12, 14833.