Highly efficient carbazolylgold(iii) dendrimers based on thermally activated delayed fluorescence and their application in solution-processed organic light-emitting devices†‡ † Dedicated to Professor Christian Bruneau.‡ Electronic supplementary information (ESI) available: Thermogravimetric analysis; PL spectra of the gold(iii) dendrimers in solid-state thin films; simulated UV-vis spectra of the gold(iii) complexes; spatial plots of selected frontier MOs; orbital energy diagrams; plots of the spin density of the emissive states; TDDFT/CPCM orbital and excitation energies; Cartesian coordinates; EL spectra and EQEs of the gold(iii) OLEDs. See DOI: 10.1039/d1sc03690d

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 diodes (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 1305 and 322 h at 100 cd m−2, respectively, representing the first demonstration of operationally stable solution-processed OLEDs based on gold(iii) dendrimers. A new class of carbazolylgold(iii) C^C^N dendrimers with thermally activated delayed fluorescence properties has been designed and synthesized for the realzaqtion of operationally stable solution-processed organic light-emitting devices.

SUBMITTER: Li L 

PROVIDER: S-EPMC8597830 | biostudies-literature |

REPOSITORIES: biostudies-literature