Suppression of the keto-emission in polyfluorene light-emitting diodes: Experiments and models

Xiao Hui Yang; Frank Jaiser; Dieter Neher; Padreyia V. Lawson; Jean Luc Brédas; Egbert Zojer; Roland Güntner; Patricia Scanduicci De Freitas; Michael Forster; Ulli Scherf

doi:10.1002/adfm.200305012

Suppression of the keto-emission in polyfluorene light-emitting diodes: Experiments and models

Xiao Hui Yang^*, Frank Jaiser, Dieter Neher, Padreyia V. Lawson, Jean Luc Brédas, Egbert Zojer, Roland Güntner, Patricia Scanduicci De Freitas, Michael Forster, Ulli Scherf

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

58 Scopus citations

Abstract

The spectral characteristics of polyfluorene (PF)-based light-emitting diodes (LEDs) containing a defined low concentration of either keto-defects or of the polymer poly(9,9-octylfluorene-co-benzothiadiazole) (F8BT) are presented. Both types of blend layers were tested in different device configurations with respect to the relative and absolute intensities of green and blue emission components. It is shown that blending hole-transporting molecules into the emission layer at low concentration or incorporation of a suitable hole-transporting layer reduces the green emission contribution in the electroluminescence (EL) spectrum of the PF:F8BT blend, which is similar to what is observed for the keto-containing PF layer. We conclude that the keto-defects in PF homopolymer layers mainly constitute weakly emissive electron traps, in agreement with the results of quantum-mechanical calculations.

Original language	English (US)
Pages (from-to)	1097-1104
Number of pages	8
Journal	Advanced Functional Materials
Volume	14
Issue number	11
DOIs	https://doi.org/10.1002/adfm.200305012
State	Published - Nov 2004
Externally published	Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
General Chemistry
Biomaterials
General Materials Science
Condensed Matter Physics
Electrochemistry

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10.1002/adfm.200305012

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@article{041c140b821645788c644347fab7cbb9,

title = "Suppression of the keto-emission in polyfluorene light-emitting diodes: Experiments and models",

abstract = "The spectral characteristics of polyfluorene (PF)-based light-emitting diodes (LEDs) containing a defined low concentration of either keto-defects or of the polymer poly(9,9-octylfluorene-co-benzothiadiazole) (F8BT) are presented. Both types of blend layers were tested in different device configurations with respect to the relative and absolute intensities of green and blue emission components. It is shown that blending hole-transporting molecules into the emission layer at low concentration or incorporation of a suitable hole-transporting layer reduces the green emission contribution in the electroluminescence (EL) spectrum of the PF:F8BT blend, which is similar to what is observed for the keto-containing PF layer. We conclude that the keto-defects in PF homopolymer layers mainly constitute weakly emissive electron traps, in agreement with the results of quantum-mechanical calculations.",

author = "Yang, {Xiao Hui} and Frank Jaiser and Dieter Neher and Lawson, {Padreyia V.} and Br{\'e}das, {Jean Luc} and Egbert Zojer and Roland G{\"u}ntner and {De Freitas}, {Patricia Scanduicci} and Michael Forster and Ulli Scherf",

year = "2004",

month = nov,

doi = "10.1002/adfm.200305012",

language = "English (US)",

volume = "14",

pages = "1097--1104",

journal = "Advanced Functional Materials",

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T1 - Suppression of the keto-emission in polyfluorene light-emitting diodes

T2 - Experiments and models

AU - Yang, Xiao Hui

AU - Jaiser, Frank

AU - Neher, Dieter

AU - Lawson, Padreyia V.

AU - Brédas, Jean Luc

AU - Zojer, Egbert

AU - Güntner, Roland

AU - De Freitas, Patricia Scanduicci

AU - Forster, Michael

AU - Scherf, Ulli

PY - 2004/11

Y1 - 2004/11

N2 - The spectral characteristics of polyfluorene (PF)-based light-emitting diodes (LEDs) containing a defined low concentration of either keto-defects or of the polymer poly(9,9-octylfluorene-co-benzothiadiazole) (F8BT) are presented. Both types of blend layers were tested in different device configurations with respect to the relative and absolute intensities of green and blue emission components. It is shown that blending hole-transporting molecules into the emission layer at low concentration or incorporation of a suitable hole-transporting layer reduces the green emission contribution in the electroluminescence (EL) spectrum of the PF:F8BT blend, which is similar to what is observed for the keto-containing PF layer. We conclude that the keto-defects in PF homopolymer layers mainly constitute weakly emissive electron traps, in agreement with the results of quantum-mechanical calculations.

AB - The spectral characteristics of polyfluorene (PF)-based light-emitting diodes (LEDs) containing a defined low concentration of either keto-defects or of the polymer poly(9,9-octylfluorene-co-benzothiadiazole) (F8BT) are presented. Both types of blend layers were tested in different device configurations with respect to the relative and absolute intensities of green and blue emission components. It is shown that blending hole-transporting molecules into the emission layer at low concentration or incorporation of a suitable hole-transporting layer reduces the green emission contribution in the electroluminescence (EL) spectrum of the PF:F8BT blend, which is similar to what is observed for the keto-containing PF layer. We conclude that the keto-defects in PF homopolymer layers mainly constitute weakly emissive electron traps, in agreement with the results of quantum-mechanical calculations.

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U2 - 10.1002/adfm.200305012

DO - 10.1002/adfm.200305012

M3 - Article

AN - SCOPUS:10644271786

SN - 1616-301X

VL - 14

SP - 1097

EP - 1104

JO - Advanced Functional Materials

JF - Advanced Functional Materials

IS - 11

ER -

Suppression of the keto-emission in polyfluorene light-emitting diodes: Experiments and models

Abstract

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