Tb-containing electroluminescent polymer with both electron- and hole-transporting side groups for single layer light emitting diodes

We developed a series of high-performance blue light-emitting polymers that contain hole-transport moieties comprising carbazole or triphenylamine substituents in the side chains of random copolymer poly(fluorene-co-dibenzothiophene-S,S-dioxide) (PFSO).

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Tb-containing electroluminescent polymer with both electron- and hole-transporting side groups for single layer light emitting diodes

Synthetic Metals ◽

10.1016/j.synthmet.2004.03.011 ◽

2004 ◽

Vol 144 (3) ◽

pp. 259-263 ◽

Cited By ~ 17

Author(s):

Lichang Zeng ◽

Mujie Yang ◽

Peng Wu ◽

Hui Ye ◽

Xu Liu

Keyword(s):

Light Emitting Diodes ◽

Single Layer ◽

Light Emitting ◽

Hole Transporting

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Light-Emitting Diodes with Voltage-Switchable Colors from Semiconducting Polymer/Polymer Heterojunctions

MRS Proceedings ◽

10.1557/proc-488-539 ◽

1997 ◽

Vol 488 ◽

Cited By ~ 3

Author(s):

Xuejun Zhang ◽

Samson A. Jenekhe

Keyword(s):

Light Emitting Diodes ◽

Single Layer ◽

Phenylene Vinylene ◽

Light Sources ◽

Semiconducting Polymer ◽

Electroluminescent Devices ◽

Light Emitting ◽

Color Changes ◽

Hole Transporting ◽

Rigid Rod

AbstractReversible electroluminescence color changes with applied voltage have been observed in light-emitting diodes fabricated from semiconducting polymer heterojunctions consisting of an electron transporting polybenzobisthiazole and hole transporting poly(p-phenylene vinylene) when layer thicknesses are less than 60–100 nm. Enhanced device performances such as lower turn-on voltage and higher efficiency and luminance were also obtained compared to single-layer devices. The observed voltage-switchable emission colors in these nanoscale heterojunction light sources can be understood in terms of spatial confinement effects which are related to field-dependent charge transport and trapping processes in the materials. These results also demonstrate the use of new high temperature rigid-rod polymers as electron transport and emissive layers in electroluminescent devices.

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High efficiency blue organic light-emitting diodes with below-bandgap electroluminescence

Nature Communications ◽

10.1038/s41467-021-25135-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Maria Vasilopoulou ◽

Abd. Rashid bin Mohd Yusoff ◽

Matyas Daboczi ◽

Julio Conforto ◽

Anderson Emanuel Ximim Gavim ◽

...

Keyword(s):

High Efficiency ◽

Light Emitting Diodes ◽

High Mobility ◽

Organic Light Emitting Diodes ◽

Triplet Energy ◽

Material Interface ◽

Light Emitting ◽

Thermally Activated ◽

Organic Light ◽

Hole Transporting

AbstractBlue organic light-emitting diodes require high triplet interlayer materials, which induce large energetic barriers at the interfaces resulting in high device voltages and reduced efficiencies. Here, we alleviate this issue by designing a low triplet energy hole transporting interlayer with high mobility, combined with an interface exciplex that confines excitons at the emissive layer/electron transporting material interface. As a result, blue thermally activated delay fluorescent organic light-emitting diodes with a below-bandgap turn-on voltage of 2.5 V and an external quantum efficiency (EQE) of 41.2% were successfully fabricated. These devices also showed suppressed efficiency roll-off maintaining an EQE of 34.8% at 1000 cd m−2. Our approach paves the way for further progress through exploring alternative device engineering approaches instead of only focusing on the demanding synthesis of organic compounds with complex structures.

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