White-light-emitting diodes based on iridium complexes via efficient energy transfer from a conjugated polymer

被引：152

作者：

Kim, TH

Lee, HK

Park, OO

Chin, BD

Lee, SH

Kim, JK

机构：

[1] Korea Adv Inst Sci & Technol, Dept Chem & Biomol Engn, Taejon 305701, South Korea

[2] Korea Adv Inst Sci & Technol, Optoelect Mat Res Ctr, Seoul 130650, South Korea

来源：

ADVANCED FUNCTIONAL MATERIALS | 2006年 / 16卷 / 05期

关键词：

D O I：

10.1002/adfm.200500621

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Efficient white-light-emitting diodes (WLEDs) have been developed using a polyfluorene-type blue-emitting conjugated polymer doped with green and red phosphorescent dyes. The emission spectrum of the conjugated polymer, which has a very high luminescent efficiency, shows a large spectral overlap with the absorbance of green and red iridium complexes. Also, efficient energy transfer from the conjugated polymer to the iridium complexes is observed. Poly(N-vinyl carbazole) is used to improve the miscibility between conjugated polymer and iridium complexes because of their poor chemical compatibility and phase separation. A white emission spectrum is easily obtained by varying the contents of the three materials and controlling the phase morphology. Moreover, these WLEDs show a voltage-independent electroluminescence owing to the threshold and driving voltage of the three materials being similar as a result of energy transfer.

引用

收藏

页码：611 / 617

页数：7

相关论文

共 28 条

[1] Phosphorescent materials for application to organic light emitting devices [J].

Baldo, MA ;

Thompson, ME ;

Forrest, SR .

PURE AND APPLIED CHEMISTRY, 1999, 71 (11) :2095-2106

[2] Highly efficient phosphorescent emission from organic electroluminescent devices [J].

Baldo, MA ;

O'Brien, DF ;

You, Y ;

Shoustikov, A ;

Sibley, S ;

Thompson, ME ;

Forrest, SR .

NATURE, 1998, 395 (6698) :151-154

[3] Correlating structure with fluorescence emission in phase-separated conjugated-polymer blends [J].

Chappell, J ;

Lidzey, DG ;

Jukes, PC ;

Higgins, AM ;

Thompson, RL ;

O'Connor, S ;

Grizzi, I ;

Fletcher, R ;

O'Brien, J ;

Geoghegan, M ;

Jones, RAL .

NATURE MATERIALS, 2003, 2 (09) :616-621

[4] Improved blue light-emitting polymeric device by the tuning of drift mobility and charge balance [J].

Chin, BD ;

Suh, MC ;

Lee, ST ;

Chung, HK ;

Lee, CH .

APPLIED PHYSICS LETTERS, 2004, 84 (10) :1777-1779

[5] White electrophosphorescence from semiconducting polymer blends [J].

Gong, X ;

Ma, WL ;

Ostrowski, JC ;

Bazan, GC ;

Moses, D ;

Heeger, AJ .

ADVANCED MATERIALS, 2004, 16 (07) :615-+

[6] Multilayer polymer light-emitting diodes: White-light emission with high efficiency [J].

Gong, X ;

Wang, S ;

Moses, D ;

Bazan, GC ;

Heeger, AJ .

ADVANCED MATERIALS, 2005, 17 (17) :2053-+

[7] Phosphorescence from iridium complexes doped into polymer blends [J].

Gong, X ;

Lim, SH ;

Ostrowski, JC ;

Moses, D ;

Bardeen, CJ ;

Bazan, GC .

JOURNAL OF APPLIED PHYSICS, 2004, 95 (03) :948-953

[8] White light electrophosphorescence from polyfluorene-based light-emitting diodes: Utilization of fluorenone defects [J].

Gong, X ;

Moses, D ;

Heeger, AJ ;

Xiao, S .

JOURNAL OF PHYSICAL CHEMISTRY B, 2004, 108 (25) :8601-8605

[9] Electrophosphorescence from a polymer guest-host system with an iridium complex as guest: Forster energy transfer and charge trapping [J].

Gong, X ;

Ostrowski, JC ;

Moses, D ;

Bazan, GC ;

Heeger, AJ .

ADVANCED FUNCTIONAL MATERIALS, 2003, 13 (06) :439-444

[10] White light emission from a polymer blend light emitting diode [J].

Granstrom, M ;

Inganas, O .

APPLIED PHYSICS LETTERS, 1996, 68 (02) :147-149