Excitation energy transfer and spatial exciton confinement in polyfluorene blends for application in light-emitting diodes

AbstractThe conjugated ladder-type poly(paraphenylene) is an attractive material for blue polymer light emitting devices (PLED). Blending the active layer with small amounts of a red emitting guest polymer, the emission shifts from blue to red with increasing guest concentration due to efficient excitation energy transfer. The results of photoluminescence detected magnetic resonance, electroluminescence detected magnetic resonance measurements and current detected magnetic resonance measurements on PLEDs based on 0.05w%/o - 2w%/o red emitting poly(perylene-co-diethynylbenzene) (PPDB) in the active layer of the PLED are presented and discussed.

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Intramolecular Excitation Energy Transfer from Visible-light Absorbing Chlorophyll Derivatives to a Near-infrared-light Emitting Boron Dipyrromethene Moiety

Chemistry Letters ◽

10.1246/cl.2010.953 ◽

2010 ◽

Vol 39 (9) ◽

pp. 953-955 ◽

Cited By ~ 18

Author(s):

Yumiko Kataoka ◽

Yutaka Shibata ◽

Hitoshi Tamiaki

Keyword(s):

Energy Transfer ◽

Visible Light ◽

Excitation Energy ◽

Near Infrared ◽

Excitation Energy Transfer ◽

Infrared Light ◽

Near Infrared Light ◽

Light Emitting ◽

Boron Dipyrromethene ◽

Chlorophyll Derivatives

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RGB Emission through Controlled Donor Self-Assembly and Modulation of Excitation Energy Transfer: A Novel Strategy to White-Light-Emitting Organogels

Advanced Materials ◽

10.1002/adma.200802932 ◽

2009 ◽

Vol 21 (20) ◽

pp. 2059-2063 ◽

Cited By ~ 234

Author(s):

Chakkooth Vijayakumar ◽

Vakayil K. Praveen ◽

Ayyappanpillai Ajayaghosh

Keyword(s):

Energy Transfer ◽

Excitation Energy ◽

White Light ◽

Self Assembly ◽

Excitation Energy Transfer ◽

Light Emitting ◽

Novel Strategy

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The Application of Poly(Phenylene) Type Polymers and Oligomers in Electroluminescent Color Displays

MRS Proceedings ◽

10.1557/proc-471-325 ◽

1997 ◽

Vol 471 ◽

Cited By ~ 1

Author(s):

S. Tasch ◽

C. Brandstätter ◽

W. Graupner ◽

S. Hampel ◽

C. Hochfilzer ◽

...

Keyword(s):

Energy Transfer ◽

Excitation Energy ◽

White Light ◽

Light Emission ◽

Excitation Energy Transfer ◽

Blue Emission ◽

Environmental Stability ◽

Large Area ◽

Light Emitting ◽

Color Conversion

ABSTRACTDue to their high photoluminescence efficiency (>30%), high environmental stability and the good charge transport properties the derivatives of poly(paraphenylene) (PPP), as the laddertype PPP (LPPP) and the oligomer hexaphenyl, are very suitable materials to realise efficient, stable, large area blue organic light-emitting diodes (OLEDs). The emission of blue OLEDs can be efficiently converted into all other emission colors either by an external color conversion technique (ECCT) or an internal color conversion technique (ICCT) and hence are very interesting for a number of display applications:Firstly, we demonstrate the realisation of efficient red-green-blue (RGB) emission colors (representing the RGB-pixels in a multicolor display) by an external CCT. In this case the blue EL device is covered with highly fluorescenct dye/matrix layers, which are excited by the blue emission and emit photoluminescence light in a lower energetic range.Secondly, a new method for producing efficient white light-emitting polymer diodes (which are interesting for e.g. backlight sources in liquid crystal displays) based on a blend of two polymers is presented: a blue light-emitting m-LPPP and a red-orange emitter poly(perylene-co-diethynylbenzene) (PPDB). The red-orange emission is created within the EL device (ICCT) by an excitation energy transfer from m-LPPP into the energetically lower lying states of PPDB. This internal excitation energy transfer is very efficient, so that only a concentration of 0.05 weight % PPDB in the polymer blend is required in order to obtain white light emission.

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Ultrafast Excitation Energy Transfer in a Blend of Light-Emitting Conjugated Polymers

Synthetic Metals ◽

10.1016/s0379-6779(98)00838-8 ◽

1999 ◽

Vol 101 (1-3) ◽

pp. 306-307 ◽

Cited By ~ 3

Author(s):

G. Cerullo ◽

W. Graupner ◽

G. Lanzani ◽

M. Nisoli ◽

E.J.W. List ◽

...

Keyword(s):

Energy Transfer ◽

Excitation Energy ◽

Conjugated Polymers ◽

Excitation Energy Transfer ◽

Light Emitting

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High-performance quasi-2D perovskite light-emitting diodes: from materials to devices

Light Science & Applications ◽

10.1038/s41377-021-00501-0 ◽

2021 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Li Zhang ◽

Changjiu Sun ◽

Tingwei He ◽

Yuanzhi Jiang ◽

Junli Wei ◽

...

Keyword(s):

Energy Transfer ◽

High Performance ◽

Light Emitting Diodes ◽

Structural Characteristics ◽

Quantum Yields ◽

Research Directions ◽

Light Emitting ◽

Perovskite Materials ◽

Quantum Confinement Effects ◽

Semiconducting Properties

AbstractQuasi-two-dimensional (quasi-2D) perovskites have attracted extraordinary attention due to their superior semiconducting properties and have emerged as one of the most promising materials for next-generation light-emitting diodes (LEDs). The outstanding optical properties originate from their structural characteristics. In particular, the inherent quantum-well structure endows them with a large exciton binding energy due to the strong dielectric- and quantum-confinement effects; the corresponding energy transfer among different n-value species thus results in high photoluminescence quantum yields (PLQYs), particularly at low excitation intensities. The review herein presents an overview of the inherent properties of quasi-2D perovskite materials, the corresponding energy transfer and spectral tunability methodologies for thin films, as well as their application in high-performance LEDs. We then summarize the challenges and potential research directions towards developing high-performance and stable quasi-2D PeLEDs. The review thus provides a systematic and timely summary for the community to deepen the understanding of quasi-2D perovskite materials and resulting LED devices.

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