Trap‐Assisted Triplet Emission in Ladder‐Polymer‐Based Light‐Emitting Diodes

Elham Khodabakhshi; Charusheela Ramanan; Jasper J. Michels; Sven Bonus; Dirk Hertel; Klaus Meerholz; Michael Forster; Ulrich Scherf; Paul W. M. Blom

doi:10.1002/aelm.202000082

Trap‐Assisted Triplet Emission in Ladder‐Polymer‐Based Light‐Emitting Diodes

Elham Khodabakhshi
, Charusheela Ramanan
, Jasper J. Michels
, Sven Bonus
, Dirk Hertel
, Klaus Meerholz
, Michael Forster
, Ulrich Scherf
, Paul W. M. Blom

Research output: Contribution to Journal › Article › Academic › peer-review

Abstract

The charge transport and recombination in light-emitting diodes (LEDs) based on a methyl-substituted poly(p-phenylene) ladder polymer (Me-LPPP) are investigated. The transport is characterized by a high room-temperature hole mobility of 2 × 10−8 m2 V−1 s−1 combined with anomalously strong electron trapping. Their electroluminescence (EL) spectrum is characterized by a blue singlet emission, a broad green featureless peak, and a yellow-orange triplet emission. The voltage dependence of the EL spectrum and negative contribution to the capacitance indicate that the triplet-emission is of trap-assisted nature, consistent with the strong electron trapping. Consequently, the color purity of the blue emissive Me-LPPP polymer LEDs can be strongly improved using trap dilution.

Original language	English
Article number	2000082
Pages (from-to)	1-6
Number of pages	6
Journal	Advanced Electronic Materials
Volume	6
Issue number	5
Early online date	19 Mar 2020
DOIs	https://doi.org/10.1002/aelm.202000082
Publication status	Published - May 2020
Externally published	Yes

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 7 Affordable and Clean Energy

Access to Document

10.1002/aelm.202000082

Persistent URL (handle)

Persistent link

Cite this

@article{a8b7202ecc734fe79d9305bab0c1bca2,

title = "Trap‐Assisted Triplet Emission in Ladder‐Polymer‐Based Light‐Emitting Diodes",

abstract = "The charge transport and recombination in light-emitting diodes (LEDs) based on a methyl-substituted poly(p-phenylene) ladder polymer (Me-LPPP) are investigated. The transport is characterized by a high room-temperature hole mobility of 2 × 10−8 m2 V−1 s−1 combined with anomalously strong electron trapping. Their electroluminescence (EL) spectrum is characterized by a blue singlet emission, a broad green featureless peak, and a yellow-orange triplet emission. The voltage dependence of the EL spectrum and negative contribution to the capacitance indicate that the triplet-emission is of trap-assisted nature, consistent with the strong electron trapping. Consequently, the color purity of the blue emissive Me-LPPP polymer LEDs can be strongly improved using trap dilution.",

author = "Elham Khodabakhshi and Charusheela Ramanan and Michels, \{Jasper J.\} and Sven Bonus and Dirk Hertel and Klaus Meerholz and Michael Forster and Ulrich Scherf and Blom, \{Paul W. M.\}",

year = "2020",

month = may,

doi = "10.1002/aelm.202000082",

language = "English",

volume = "6",

pages = "1--6",

journal = "Advanced Electronic Materials",

issn = "2199-160X",

publisher = "John Wiley and Sons Inc.",

number = "5",

}

TY - JOUR

T1 - Trap‐Assisted Triplet Emission in Ladder‐Polymer‐Based Light‐Emitting Diodes

AU - Khodabakhshi, Elham

AU - Ramanan, Charusheela

AU - Michels, Jasper J.

AU - Bonus, Sven

AU - Hertel, Dirk

AU - Meerholz, Klaus

AU - Forster, Michael

AU - Scherf, Ulrich

AU - Blom, Paul W. M.

PY - 2020/5

Y1 - 2020/5

N2 - The charge transport and recombination in light-emitting diodes (LEDs) based on a methyl-substituted poly(p-phenylene) ladder polymer (Me-LPPP) are investigated. The transport is characterized by a high room-temperature hole mobility of 2 × 10−8 m2 V−1 s−1 combined with anomalously strong electron trapping. Their electroluminescence (EL) spectrum is characterized by a blue singlet emission, a broad green featureless peak, and a yellow-orange triplet emission. The voltage dependence of the EL spectrum and negative contribution to the capacitance indicate that the triplet-emission is of trap-assisted nature, consistent with the strong electron trapping. Consequently, the color purity of the blue emissive Me-LPPP polymer LEDs can be strongly improved using trap dilution.

AB - The charge transport and recombination in light-emitting diodes (LEDs) based on a methyl-substituted poly(p-phenylene) ladder polymer (Me-LPPP) are investigated. The transport is characterized by a high room-temperature hole mobility of 2 × 10−8 m2 V−1 s−1 combined with anomalously strong electron trapping. Their electroluminescence (EL) spectrum is characterized by a blue singlet emission, a broad green featureless peak, and a yellow-orange triplet emission. The voltage dependence of the EL spectrum and negative contribution to the capacitance indicate that the triplet-emission is of trap-assisted nature, consistent with the strong electron trapping. Consequently, the color purity of the blue emissive Me-LPPP polymer LEDs can be strongly improved using trap dilution.

UR - https://id.culturegraph.org/DNB:1260759563

U2 - 10.1002/aelm.202000082

DO - 10.1002/aelm.202000082

M3 - Article

SN - 2199-160X

VL - 6

SP - 1

EP - 6

JO - Advanced Electronic Materials

JF - Advanced Electronic Materials

IS - 5

M1 - 2000082

ER -

Trap‐Assisted Triplet Emission in Ladder‐Polymer‐Based Light‐Emitting Diodes

Abstract

UN SDGs

Access to Document

Persistent URL (handle)

Other files and links

Fingerprint

Cite this