TY - JOUR
T1 - Carbazole dendrimers as solution-processable thermally activated delayed-fluorescence materials
AU - Albrecht, Ken
AU - Matsuoka, Kenichi
AU - Fujita, Katsuhiko
AU - Yamamoto, Kimihisa
PY - 2015/5/4
Y1 - 2015/5/4
N2 - Recently, thermally activated delayed fluorescence (TADF) materials have received increasing attention as effective emitters for organic light-emitting diodes (OLEDs). However, most of them are usually employed as dopants in a host material. In this report, carbazole dendrimers with a triphenyl-s-triazine core are reported, which are the first solution-processable, non-doped, high-molecular-weight TADF materials. The dendrimers were obtained by a new and facile synthetic route using the tert-butyldimethylsilyl moiety as a protecting group. All dendrimers showed TADF in toluene. Measurements of the temperature-dependent luminescence lifetime revealed that spin-coated neat films also showed TADF with moderate quantum yields. OLED devices incorporating these dendrimers as spin-coated emitting layers gave external quantum efficiencies of up to a 3.4%, which suggests that this device is harvesting triplet excitons. This result indicates that carbazole dendrimers with attached acceptors are potential TADF materials owing to their polarized electronic structure (with HOMO-LUMO separation). Fluorescent dendrimers: Carbazole dendrimers with a triphenyl-s-triazine core have been developed as the first solution-processable, non-doped, and high-molecular-weight thermally activated delayed fluorescence (TADF) materials. OLED devices with such dendrimers as the spin-coated emitting layer displayed external quantum efficiencies of up to 3.4%, which suggests that this device is harvesting triplet excitons.
AB - Recently, thermally activated delayed fluorescence (TADF) materials have received increasing attention as effective emitters for organic light-emitting diodes (OLEDs). However, most of them are usually employed as dopants in a host material. In this report, carbazole dendrimers with a triphenyl-s-triazine core are reported, which are the first solution-processable, non-doped, high-molecular-weight TADF materials. The dendrimers were obtained by a new and facile synthetic route using the tert-butyldimethylsilyl moiety as a protecting group. All dendrimers showed TADF in toluene. Measurements of the temperature-dependent luminescence lifetime revealed that spin-coated neat films also showed TADF with moderate quantum yields. OLED devices incorporating these dendrimers as spin-coated emitting layers gave external quantum efficiencies of up to a 3.4%, which suggests that this device is harvesting triplet excitons. This result indicates that carbazole dendrimers with attached acceptors are potential TADF materials owing to their polarized electronic structure (with HOMO-LUMO separation). Fluorescent dendrimers: Carbazole dendrimers with a triphenyl-s-triazine core have been developed as the first solution-processable, non-doped, and high-molecular-weight thermally activated delayed fluorescence (TADF) materials. OLED devices with such dendrimers as the spin-coated emitting layer displayed external quantum efficiencies of up to 3.4%, which suggests that this device is harvesting triplet excitons.
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U2 - 10.1002/anie.201500203
DO - 10.1002/anie.201500203
M3 - Article
AN - SCOPUS:85027938778
VL - 54
SP - 5677
EP - 5682
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
SN - 1433-7851
IS - 19
ER -