Room temperature lifetime of triplet excitons in fluorescent host/guest systems

被引：36

作者：

Lehnhardt, Marcus ^{[1
]}

Riedl, Thomas ^{[2
]}

Rabe, Torsten ^{[1
]}

Kowalsky, Wolfgang ^{[1
]}

机构：

[1] Tech Univ Carolo Wilhelmina Braunschweig, Inst Hochfrequenztech, D-38106 Braunschweig, Germany

[2] Berg Univ Wuppertal, Inst Elect Devices, D-42119 Wuppertal, Germany

来源：

ORGANIC ELECTRONICS | 2011年 / 12卷 / 03期

关键词：

Triplet-triplet annihilation; Host/guest system; Fluorescent OLED; Organic solid state laser; SINGLET-TRIPLET; DECAY DYNAMICS; ANNIHILATION; ELECTROLUMINESCENCE; EFFICIENCY; STATES; DCM; RECOMBINATION; GENERATION; MECHANISM;

D O I：

10.1016/j.orgel.2010.12.017

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We studied the triplet decay dynamics in the fluorescent polymer-polymer host/guest system F8BT/MEH-PPV and in the small molecule host/guest system Alq(3)/DCM. The triplet lifetime was determined by a highly sensitive time-resolved measurement of the triplet state absorption via a pump and probe experiment in a waveguide structure. We were able to identify triplet-triplet annihilation as a major decay mechanism of triplet states in the pristine amorphous organic materials at room temperature (rate constant: k(TT) approximate to 10 (12) cm(3) s (1)). On the contrary, the host/guest systems showed a significantly increased triplet lifetime caused by a reduced triplet-triplet annihilation rate which we attribute to a substantially lowered mobility of the localized triplet excitons. Our results are expected to be of paramount importance for organic light emitting devices based on fluorescent emitters (e.g. organic lasers and organic light emitting diodes). (C) 2011 Elsevier B.V. All rights reserved.

引用

页码：486 / 491

页数：6

共 44 条

[1] Transient analysis of organic electrophosphorescence. II. Transient analysis of triplet-triplet annihilation [J].

Baldo, MA ;

Adachi, C ;

Forrest, SR .

PHYSICAL REVIEW B, 2000, 62 (16) :10967-10977

[2] Triplet States of the Nonlinear Optical Chromophore DCM in Single Crystals of Potassium Hydrogen Phthalate and Their Relationship to Single-Molecule Dark States [J].

Barbon, Antonio ;

Bott, Eric D. ;

Brustolon, Marina ;

Fabris, Marianna ;

Kahr, Bart ;

Kaminsky, Werner ;

Reid, Philip J. ;

Wong, Susanna M. ;

Wustholz, Kristin L. ;

Zanre, Roberto .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2009, 131 (32) :11548-11557

[3] Characterization of the triplet state of tris(8-hydroxyquinoline)aluminium(III) in benzene solution [J].

Burrows, HD ;

Fernandes, M ;

de Melo, JS ;

Monkman, AP ;

Navaratnam, S .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2003, 125 (50) :15310-15311

[4] S1∼>T1 intersystem crossing in π-conjugated organic polymers [J].

Burrows, HD ;

de Melo, JS ;

Serpa, C ;

Arnaut, LG ;

Monkman, AP ;

Hamblett, I ;

Navaratnam, S .

JOURNAL OF CHEMICAL PHYSICS, 2001, 115 (20) :9601-9606

[5] The effect of broken conjugation on the optical absorption spectra of the triplet states of isolated chains of poly(phenylene vinylene)s [J].

Candeias, LP ;

Padmanaban, G ;

Ramakrishnan, S .

CHEMICAL PHYSICS LETTERS, 2001, 349 (5-6) :394-398

[6] Fluorescence lifetime and nonradiative relaxation dynamics of DCM in nonpolar solvent [J].

Chang, CW ;

Kao, YT ;

Diau, EWG .

CHEMICAL PHYSICS LETTERS, 2003, 374 (1-2) :110-118

[7] Delayed fluorescence and phosphorescence of tris-(8-hydroxyquinoline)aluminum (Alq3) and their temperature dependence [J].

Cölle, M ;

Gärditz, C .

JOURNAL OF LUMINESCENCE, 2004, 110 (04) :200-206

[8] Triplet energy transfer in conjugated polymers.: I.: Experimental investigation of a weakly disordered compound [J].

Devi, Lekshmi Sudha ;

Al-Suti, Mohammad K. ;

Dosche, Carsten ;

Khan, Muhammad S. ;

Friend, Richard H. ;

Koehler, Anna .

PHYSICAL REVIEW B, 2008, 78 (04)

[9] Triplet energy transfer in conjugated polymers.: II.: A polaron theory description addressing the influence of disorder [J].

Fishchuk, Ivan I. ;

Kadashchuk, Andrey ;

Devi, Lekshmi Sudha ;

Heremans, Paul ;

Baessler, Heinz ;

Koehler, Anna .

PHYSICAL REVIEW B, 2008, 78 (04)

[10] Enhanced triplet exciton generation in polyfluorene blends [J].

Ford, TA ;

Avilov, I ;

Beljonne, D ;

Greenham, NC .

PHYSICAL REVIEW B, 2005, 71 (12)

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