The contribution of triplet-triplet annihilation to the lifetime and efficiency of fluorescent polymer organic light emitting diodes

被引:75
作者
King, S. M. [1 ]
Cass, M. [1 ]
Pintani, M. [1 ]
Coward, C. [1 ]
Dias, F. B. [2 ]
Monkman, A. P. [2 ]
Roberts, M. [1 ]
机构
[1] Cambridge Display Technol Ltd, Cambridge CB23 6DW, England
[2] Univ Durham, Dept Phys, Durham Photon Mat Inst, Durham DH1 3LE, England
基金
英国工程与自然科学研究理事会;
关键词
DEPENDENT EXCITON FORMATION; DELAYED ELECTROLUMINESCENCE; DEGRADATION; MECHANISM; DECAY;
D O I
10.1063/1.3561430
中图分类号
O59 [应用物理学];
学科分类号
摘要
We demonstrate that the fast initial decay of a prototypical fluorescent polymer based organic light emitting diode device is related to the contribution that triplet-triplet annihilation makes to the device efficiency. We show that, during typical operating conditions, approximately 20% of the device efficiency originates from the production of singlet excitons by triplet-triplet annihilation. During prolonged device operation, the triplet excitons are quenched much more easily than the emissive singlets; thus, the contribution to the efficiency from triplet-triplet annihilation is lost during the early stages of the device lifetest. The fast initial decay of the device luminance can be removed by incorporating a triplet quenching additive into the active layer to remove any effect of triplet-triplet annihilation; this yields an increase in the device lifetime of greater than 3x and an even more significant improvement in the initial luminance decay. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3561430]
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页数:5
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共 28 条
[1]   Improved color purity and efficiency of blue organic light-emitting diodes via suppression of exciplex formation [J].
Chen, BJ ;
Zhang, XH ;
Lin, XQ ;
Kwong, HL ;
Wong, NB ;
Lee, CS ;
Gambling, WA ;
Lee, ST .
SYNTHETIC METALS, 2001, 118 (1-3) :193-196
[2]   White organic light-emitting devices with a bipolar transport layer between blue fluorescent and orange phosphorescent emitting layers [J].
Chen, Ping ;
Xie, Wenfa ;
Li, Jiang ;
Guan, Tao ;
Duan, Yu ;
Zhao, Yi ;
Liu, Shiyong ;
Ma, Chunsheng ;
Zhang, Liying ;
Li, Bin .
APPLIED PHYSICS LETTERS, 2007, 91 (02)
[3]   ELECTRIC-FIELD-INDUCED PHOTOLUMINESCENCE QUENCHING IN THIN-FILM LIGHT-EMITTING-DIODES BASED ON POLY(PHENYL-P-PHENYLENE VINYLENE) [J].
DEUSSEN, M ;
SCHEIDLER, M ;
BASSLER, H .
SYNTHETIC METALS, 1995, 73 (02) :123-129
[4]   Triplet formation in polyfluorene devices [J].
Dhoot, AS ;
Greenham, NC .
ADVANCED MATERIALS, 2002, 14 (24) :1834-1837
[5]   Triplet formation and decay in conjugated polymer devices [J].
Dhoot, AS ;
Ginger, DS ;
Beljonne, D ;
Shuai, Z ;
Greenham, NC .
CHEMICAL PHYSICS LETTERS, 2002, 360 (3-4) :195-201
[6]   Organic displays come of age [J].
Fyfe, David .
NATURE PHOTONICS, 2009, 3 (08) :453-455
[7]   Comparison of thermal and electrical degradation effects in polyfluorenes [J].
Gamerith, S ;
Gaal, M ;
Romaner, L ;
Nothofer, HG ;
Güntner, R ;
de Freitas, PS ;
Scherf, U ;
List, EJW .
SYNTHETIC METALS, 2003, 139 (03) :855-858
[8]   Triplet-triplet annihilation in a poly(fluorene)-derivative [J].
Hertel, D ;
Bässler, H ;
Guentner, R ;
Scherf, U .
JOURNAL OF CHEMICAL PHYSICS, 2001, 115 (21) :10007-10013
[9]   ELECTRICAL AND OPTICAL CHARACTERIZATION OF POLY(PHENYLENE-VINYLENE) LIGHT-EMITTING-DIODES [J].
KARG, S ;
RIESS, W ;
DYAKONOV, V ;
SCHWOERER, M .
SYNTHETIC METALS, 1993, 54 (1-3) :427-433
[10]   Spin-cast thin semiconducting polymer interlayer for improving device efficiency of polymer light-emitting diodes [J].
Kim, JS ;
Friend, RH ;
Grizzi, I ;
Burroughes, JH .
APPLIED PHYSICS LETTERS, 2005, 87 (02)