B1 Non-refereed article in a scientific journal
Effect of the Host on Deep-Blue Organic Light-Emitting Diodes Based on a TADF Emitter for Roll-Off Suppressing
Authors: Kumar M, Pereira L
Publisher: MDPI
Publication year: 2019
Journal: Nanomaterials
Journal name in source: NANOMATERIALS
Journal acronym: NANOMATERIALS-BASEL
Article number: ARTN 1307
Volume: 9
Issue: 9
Number of pages: 9
DOI: https://doi.org/10.3390/nano9091307
Abstract
To achieve significant efficiency and low roll-off in thermally activated delayed fluorescence (TADF) material organic light-emitting diodes (OLEDs), it is essential to choose a host that has suitable high triplet energy (T-1) and bipolar character to boost the TADF characteristics as a dopant and avoid exciton annihilation. Herein, we present the effect of different host materials on the efficiency of organic light-emitting diodes (OLEDs) based on bis[4-(3,6 dimethoxycarbazole)phenyl]sulfone (DMOC-DPS) deep-blue emitter. The devices with 10 wt.% of an emitter in different electron types of host bis[2-(diphenylphosphino) phenyl] ether oxide (DPEPO), and hole types of host 1,3-bis(N-carbazolyl)benzene (mCP), were fabricated to study the effect on device performance. The results show that an external quantum efficiency (EQE) of 4% and maximum current efficiency (?(c)) up to 5.77 cd/A with high luminescence (l(max)) 8185 cd/m(2) in DPEPO was achieved, compared to 2.63% EQE, ?(c) 4.12 cd/A with l(max) 5338 cd/m(2) in mCP in a very simple device structure. As a remarkable result, the roll-off is suppressed at 1000 cd/m(2), and for maximum brightness, the roll-off is less than 50%. Further general applications are discussed.
To achieve significant efficiency and low roll-off in thermally activated delayed fluorescence (TADF) material organic light-emitting diodes (OLEDs), it is essential to choose a host that has suitable high triplet energy (T-1) and bipolar character to boost the TADF characteristics as a dopant and avoid exciton annihilation. Herein, we present the effect of different host materials on the efficiency of organic light-emitting diodes (OLEDs) based on bis[4-(3,6 dimethoxycarbazole)phenyl]sulfone (DMOC-DPS) deep-blue emitter. The devices with 10 wt.% of an emitter in different electron types of host bis[2-(diphenylphosphino) phenyl] ether oxide (DPEPO), and hole types of host 1,3-bis(N-carbazolyl)benzene (mCP), were fabricated to study the effect on device performance. The results show that an external quantum efficiency (EQE) of 4% and maximum current efficiency (?(c)) up to 5.77 cd/A with high luminescence (l(max)) 8185 cd/m(2) in DPEPO was achieved, compared to 2.63% EQE, ?(c) 4.12 cd/A with l(max) 5338 cd/m(2) in mCP in a very simple device structure. As a remarkable result, the roll-off is suppressed at 1000 cd/m(2), and for maximum brightness, the roll-off is less than 50%. Further general applications are discussed.
UTU Research Portal