TY - JOUR
T1 - Multi-layer organic light-emitting diodes processed from solution using phosphorescent dendrimers in a polymer host
AU - Ko, Li Chun
AU - Liu, Tsung Yu
AU - Chen, Chun Yao
AU - Yeh, Chung Ling
AU - Tseng, Shin Rong
AU - Chao, Yu Chiang
AU - Meng, Hsin Fei
AU - Lo, Shih Chun
AU - Burn, Paul L.
AU - Horng, Sheng Fu
N1 - Funding Information:
This work was supported by the National Science Council of the Republic of China ( NSC NO. 97-3114-M-009-002 , NO. 97-2628-M-009-016 ) and Professor Paul L. Burn is recipient of an Australian Research Council Federation Fellowship (Project Number FF0668728 ).
PY - 2010/6
Y1 - 2010/6
N2 - A uniform dispersion of highly soluble phosphorescent dendrimer emitters is achievedby blending with a polymer host poly(9-vinylcarbazole) (PVK) containing N,N′-diphenyl-N, N′-(bis(3-methylphenyl)-[1,1-biphenyl]-4,4′- diamine (TPD) and 2-(4-biphen-4′-yl)-5-(4- tert-butylphenyl)-1,3,4- oxadiazole (PBD). No visible aggregation orself-quenching was observed for guest-to-host weight ratios of up to 33:67. The dendrimers contain a factris( 2-phenylpyridyl)iridium(III) [Ir(ppy)3] core, first generation biphenyl-based dendrons, and 2-ethylhexyloxy surface groups. The guest-host blend is used for all solution processed organic light-emitting diodes. A maximum external and current efficiency of 10.2% and 38 cd/A (at 5 V and a brightness of 50 cd/m2), and a maximum brightness of 27,000 cd/m 2 (at 14.5 V), were obtained when a CsF/Al cathode was used. Blade coating was used to fabricate a multi-layer structure that also contained an electron-transport layer. The device that had a LiF/Al cathode had a maximal efficiency of 40 cd/A corresponding to an external quantum efficiency of 10.8% (at 5 V and a brightness of 19 cd/m2). The maximum brightness of the second device was 17,840 cd/m2 at 14 V.
AB - A uniform dispersion of highly soluble phosphorescent dendrimer emitters is achievedby blending with a polymer host poly(9-vinylcarbazole) (PVK) containing N,N′-diphenyl-N, N′-(bis(3-methylphenyl)-[1,1-biphenyl]-4,4′- diamine (TPD) and 2-(4-biphen-4′-yl)-5-(4- tert-butylphenyl)-1,3,4- oxadiazole (PBD). No visible aggregation orself-quenching was observed for guest-to-host weight ratios of up to 33:67. The dendrimers contain a factris( 2-phenylpyridyl)iridium(III) [Ir(ppy)3] core, first generation biphenyl-based dendrons, and 2-ethylhexyloxy surface groups. The guest-host blend is used for all solution processed organic light-emitting diodes. A maximum external and current efficiency of 10.2% and 38 cd/A (at 5 V and a brightness of 50 cd/m2), and a maximum brightness of 27,000 cd/m 2 (at 14.5 V), were obtained when a CsF/Al cathode was used. Blade coating was used to fabricate a multi-layer structure that also contained an electron-transport layer. The device that had a LiF/Al cathode had a maximal efficiency of 40 cd/A corresponding to an external quantum efficiency of 10.8% (at 5 V and a brightness of 19 cd/m2). The maximum brightness of the second device was 17,840 cd/m2 at 14 V.
KW - Blade coating
KW - Dendrimer
KW - Organic light-emitting diodes
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U2 - 10.1016/j.orgel.2010.03.014
DO - 10.1016/j.orgel.2010.03.014
M3 - Article
AN - SCOPUS:78049511109
SN - 1566-1199
VL - 11
SP - 1005
EP - 1009
JO - Organic Electronics: physics, materials, applications
JF - Organic Electronics: physics, materials, applications
IS - 6
ER -