November 24, 2020

Download Ebook Free Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes

Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes (TADF-OLEDs)

Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes (TADF-OLEDs)
Author : Lian Duan
Publisher : Woodhead Publishing
Release Date : 2021-05-15
Category : Technology & Engineering
Total pages :515
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Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes (TADF-OLEDs) comprehensively introduces the history of TADF, along with a review of fundamental concepts. Then, TADF emitters with different colors, such as blue, green, red and NIR as well as white OLEDs are discussed in detail. Other sections cover exciplex-type TADF materials, emerging application of TADF emitters as a host in OLEDs, and applications of TADF materials in organic lasers and biosensing. Discusses green, blue, red, NIR and white TADF emitters and their design strategies for improved performance for light-emitting diode applications Addresses emerging materials, such as molecular and exciplex-based TADF materials Includes emerging applications like lasers and biosensors

White Organic Light-Emitting Diodes with Thermally Activated Delayed Fluorescence Emitters

White Organic Light-Emitting Diodes with Thermally Activated Delayed Fluorescence Emitters
Author : Dongxiang Luo
Publisher : Unknown
Release Date : 2018
Category : Technology
Total pages :129
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Recently, thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs) have attracted both academic and industrial interest due to their extraordinary characteristics, such as high efficiency, low driving voltage, bright luminance, lower power consumption, and potentially long lifetime. In this chapter, various approaches to realize white OLEDs (WOLEDs) with TADF emitters have been introduced. The recent development of WOLEDs based on all TADF emitters, WOLEDs based on TADF and conventional fluorescence emitters, and WOLEDs based on TADF and phosphorescence emitters is highlighted. Particularly, the device structures, design strategies, working mechanisms, and electroluminescent processes of the representative high-performance WOLEDs with TADF emitters are reviewed. Moreover, challenges and opportunities for further enhancement of the performance of WOLEDs with TADF emitters are presented.

Light-Emitting Diode

Light-Emitting Diode
Author : Jagannathan Thirumalai
Publisher : BoD – Books on Demand
Release Date : 2018-09-19
Category : Technology & Engineering
Total pages :168
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The broad vision of this book is to offer book lovers a comprehensive appraisal of topics in the global advancements of experimental facts, instrumentation, and practical applications of LED and OLED materials and their applications. The prime feature of this book is connected with LED and OLED materials approaches of fabrication, optimization limits, and their extensive technical applications. This book is comprised of seven chapters encompassing the importance of LEDs and OLEDs, the history of LEDs and OLEDs with necessary examples, the phototoxic-cum-bactericidal effect due to the usage of blue LED irradiation, DC network indoor and outdoor LED lighting, WLEDs with thermally activated delayed fluorescence emitters, tetradentate cyclometalated platinum (II) complex-based efficient organic LEDs, the impact of the use of large LED lighting loads in low-voltage networks, highly efficient OLEDs using thermally activated delayed fluorescent materials, and AlGaN deep ultraviolet LEDs. Individual chapters provide a base for the wide range of common bibliophiles in diversified fields, students, and researchers, who may conduct research pertinent to this book and will find simply explained basics as well as advanced principles of designated subjects related to these phenomena. The book was created from seven contributions from experts in the diversified fields of LED and OLED fabrication and technology from over 15 research institutes across the globe.

Highly Efficient OLEDs

Highly Efficient OLEDs
Author : Hartmut Yersin
Publisher : Wiley-VCH
Release Date : 2018-11-19
Category : Technology & Engineering
Total pages :608
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The essential resource that offers a comprehensive understanding of OLED optimizations Highly Efficient OLEDs. Materials Based on Thermally Activated Delayed Fluorescence (TADF) offers substantial information on the working principle of OLEDs and on new types of emitting materials (organic and inorganic). As the authors explain, OLEDs that use the Singlet-Harvesting mechanism based on the molecular property of TADF work according to a new exciton harvesting principle. Thus, low-cost emitter materials, such as Cu(I) or Ag(I) complexes as well as metal-free organic molecules, have the potential to replace high-cost rare metal complexes being currently applied in OLED technology. With contributions from an international panel of experts on the topic, the text shows how the application of new TADF materials allow for the development of efficient OLED displays and lighting systems. This new mechanism is the gateway to the third-generation of luminescent materials. This important resource: Offers a state-of-the-art compilation of the latest results in the dynamically developing field of OLED materials Is edited by a pioneer in the field of OLED material technology Contains a detailed application-oriented guide to new low-cost materials for displays and lighting Puts the focus on the emerging fields of OLED technology Written for materials scientists, solid state chemists, solid state physicists, and electronics engineers, Highly Efficient OLEDs. Materials Based on Thermally Activated Delayed Fluorescence offers a comprehensive resource to the latest advances of OLEDs based on new TADF materials.

Light-Active Functional Organic Materials

Light-Active Functional Organic Materials
Author : Hiroko Yamada,Shiki Yagai
Publisher : CRC Press
Release Date : 2019-05-22
Category : Science
Total pages :224
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Inspired by naturally occurring light-active molecular systems such as photosynthesis, scientists have long devoted their efforts to understanding how light and molecules interact. Based on a raft of knowledge on light absorption, energy migration and electron transfer, fluorescence and phosphorescence, and various photochemical reactions, light can now be utilized for energy conversion, information storage, medical applications, and development of next-generation photofunctional materials that cannot be obtained via conventional organic synthesis. This book overviews some of the cutting-edge p-conjugated molecular and polymer materials for organic photovoltaics, artificial photosynthesis, and organic light-emitting devices. It gives insights into the interactions between light and molecules and discusses sophisticated molecular designs, self-assembly and self-organization strategies, and state-of-the-art unconventional analytical methods.

A New Generation of Organic Light-Emitting Materials and Devices

A New Generation of Organic Light-Emitting Materials and Devices
Author : Shi-Jian Su,Lian Duan,Hisahiro Sasabe
Publisher : Frontiers Media SA
Release Date : 2019-11-27
Category :
Total pages :129
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Since the invention of the first efficient organic light-emitting diodes (OLEDs) by C. T. Tang and S. VanSlyke, OLEDs have attracted close interest as a promising candidate for next-generation full-color displays and future solid-state lighting sources because of a number of advantages like high brightness and contrast, high luminous efficiency, fast response time, wide viewing angle, low power consumption, and light weight. The recombination of holes and electrons under electrical excitation typically generates 25% singlet excitons and 75% triplet excitons. For traditional fluorescent OLEDs, only 25% singlet excitons can be utilized to emit light, while the other 75% triplet excitons are generally wasted through nonradiative transition. By adopting noble metal phosphorescent complexes, an internal quantum efficiency (IQE) of 100% could be achieved by utilizing both the 25% singlet excitons and 75% triplet excitons. However, these phosphors usually contain nonrenewable and highcost iridium or platinum noble metals. Most recently, unity IQE has been readily achieved through noble metal-free purely organic emitters, such as thermally activated delayed fluorescence (TADF) emitters, hybridized local and charge-transfer state (HLCT) “hot exciton” emitters, binary- or ternary-mixed donor-acceptor exciplex emitters, and neutral p radical emitters, etc. In addition, the combination of conventional p-type hole-transport and n-type electron-transport materials in an appropriate device structure can also provide an uncommon efficiency. Both strategies are essential and attractive for high-performance and low-cost full-color displays and white OLED applications. This Research Topic mainly focus on this new generation of organic light-emitting materials and devices, including design, synthesis, and characterization of light-emitting organic molecules with tunable excited states, and their structural, electrical, and photophysical properties. Contributions relating to carrier transporting materials and corresponding device engineering are also included. Two mini reviews and thirteen original research articles by recognized academic experts in their respective fields are collected in this Research Topic, which will offer a broad perspective of noble metal-free organic light emitters, including conventional fluorescent emitters, TADF emitters, HLCT emitters, exciplex emitters, aggregation-induced emission (AIE) luminogens, and their corresponding devices. We believe this eBook should attract the attention of multidisciplinary researchers in the fields of materials science, organic synthesis, and electronic device engineering, especially for those engaged in OLED-related areas.

Highly-efficient Fully Non-doped White Organic Light-emitting Diodes Consisting Entirely of Thermally Activated Delayed Fluorescence Emitters1

Highly-efficient Fully Non-doped White Organic Light-emitting Diodes Consisting Entirely of Thermally Activated Delayed Fluorescence Emitters1
Author : Anonim
Publisher : Unknown
Release Date : 2018
Category :
Total pages :129
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Abstract : A fully non-doped all-TADF strategy is proposed to fabricate simple and efficient WOLEDs based on a novel yellow TADF emitter. Abstract : Thermally activated delayed fluorescence (TADF) emitters can harvest singlet and triplet excitons for light emission to afford highly efficient organic light-emitting diode (OLED) devices, especially for all-TADF white OLEDs (WOLEDs). However, the majority of TADF emitters suffer from concentration quenching effects and require complicated doping techniques for device fabrication. Herein, we demonstrate a yellow TADF emitter that enables non-doped OLED systems, which is beneficial for the simplification of the OLED device structure and fabrication. The non-doped yellow OLED achieves a maximum external quantum efficiency (EQE) of 16.7% at a high luminance of 3600 cd m −2, in which such a high magnitude is rarely reported. More significantly, by the combination of the yellow TADF emitter with a blue TADF emitter, a fully non-doped emissive layer (EML) strategy has been demonstrated for the fabrication of an all-TADF WOLED, in which the non-doped yellow and blue TADF emissive layers are closely stacked together without any interlayers. The fully non-doped WOLEDs show a maximum EQE of up to 19.8%, along with high quality white-light emission. This is the first report regarding the fully non-doped all-TADF WOLEDs, and the presented design strategy provides a universal route towards the fabrication of simple and efficient WOLEDs.

High Efficiency and Stable Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence Emitter*Supported by the National Natural Science Foundation of China Under Grant Nos 61420106002, 51373189, 61178061, and 61227008, the Hundred Talents Program of the Chinese Academy of Sciences, the National Basic Research Program of China Under Grant No 2014CB932600, and the Start-Up Fund of the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences

High Efficiency and Stable Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence Emitter*Supported by the National Natural Science Foundation of China Under Grant Nos 61420106002, 51373189, 61178061, and 61227008, the Hundred Talents Program of the Chinese Academy of Sciences, the National Basic Research Program of China Under Grant No 2014CB932600, and the Start-Up Fund of the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences
Author : Anonim
Publisher : Unknown
Release Date : 2016
Category :
Total pages :129
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Abstract : High efficiency, stable organic light-emitting diodes (OLEDs) based on 2-pheyl-4′-carbazole-9-H-Thioxanthen-9-one-10, 10-dioxide (TXO-PhCz) with different doping concentration are constructed. The stability of the encapsulated devices are investigated in detail. The devices with the 10 wt% doped TXO-PhCz emitter layer (EML) show the best performance with a current efficiency of 52.1 cd/A, a power efficiency of 32.7 lm/W, and an external quantum efficiency (EQE) of 17.7%. The devices based on the 10 wt%-doped TXO-PhCz EML show the best operational stability with a half-life time (LT50) of 80 h, which is 8 h longer than that of the reference devices based on fac-tris(2-phenylpyridinato)iridium(III) (Ir(ppy)3 ). These indicate excellent stability of TXO-PhCz for redox and oxidation processes under electrical excitation and TXO-PhCz can be potentially used as the emitters for OLEDs with high efficiency and excellent stability. The high-performance device based on TXO-PhCz with high stability can be further improved by the optimization of the encapsulation technology and the development of a new host for TXO-PhCz.

Photoluminescent Materials and Electroluminescent Devices

Photoluminescent Materials and Electroluminescent Devices
Author : Nicola Armaroli,Henk J. Bolink
Publisher : Springer
Release Date : 2017-05-25
Category : Science
Total pages :395
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The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.

Luminescence

Luminescence
Author : Jagannathan Thirumalai
Publisher : BoD – Books on Demand
Release Date : 2016-11-10
Category : Science
Total pages :388
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The aim of this book is to give readers a broad review of topical worldwide advancements in theoretical and experimental facts, instrumentation and practical applications erudite by luminescent materials and their prospects in dealing with different types of luminescence like photoluminescence, electroluminescence, thermo-luminescence, triboluminescence, bioluminescence design and applications. The additional part of this book deals with the dynamics, rare-earth ions, photon down-/up-converting materials, luminescence dating, lifetime, bioluminescence microscopical perspectives and prospects towards the basic research or for more advanced applications. This book is divided into four main sections: luminescent materials and their associated phenomena; photo-physical properties and their emerging applications; thermoluminescence dating: from theory to applications, and bioluminescence perspectives and prospects. Individual chapters should serve the broad spectrum of common readers of diverse expertise, layman, students and researchers, who may in this book find easily elucidated fundamentals as well as progressive principles of specific subjects associated with these phenomena. This book was created by 14 contributions from experts in different fields of luminescence and technology from over 20 research institutes worldwide.

New Generation of High Efficient OLED Using Thermally Activated Delayed Fluorescent Materials

New Generation of High Efficient OLED Using Thermally Activated Delayed Fluorescent Materials
Author : Manish Kumar
Publisher : Unknown
Release Date : 2018
Category : Technology
Total pages :129
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The search for efficient materials for organic light emitting diodes is one of the most imperative research area. The focus is to obtain a bright large area emitter, limited by the low internal quantum efficiency of conventional organic emitters. Recently, a new generation of the organic materials (TADF) with a theoretical internal quantum efficiency up to 100%, opened new frameworks. However, significant challenges persist to achieve full understanding of the TADF mechanism and to improve the OLEDs stability. Starting from the photo-physical analysis, we show the relationship with the molecular electrical carrier dynamics and internal quantum efficiencies. The OLED structure, fabrication, and characterization are also discussed. Several examples for the full colour emitters are given. Special emphasis on experimental results is made, showing the major milestones already achieved in this field.

Polymers for Light-emitting Devices and Displays

Polymers for Light-emitting Devices and Displays
Author : Inamuddin,Rajender Boddula,Mohd Imran Ahamed,Abdullah M. Asiri
Publisher : John Wiley & Sons
Release Date : 2020-05-27
Category : Technology & Engineering
Total pages :288
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Polymers for Light-Emitting Devices and Displays provides an in-depth overview of fabrication methods and unique properties of polymeric semiconductors, and their potential applications for LEDs including organic electronics, displays, and optoelectronics. Some of the chapter subjects include: • The newest polymeric materials and processes beyond the classical structure of PLED • Conjugated polymers and their application in the light-emitting diodes (OLEDs & PLEDs) as optoelectronic devices. • The novel work carried out on electrospun nanofibers used for LEDs. • The roles of diversified architectures, layers, components, and their structural modifications in determining efficiencies and parameters of PLEDs as high-performance devices. • Polymer liquid crystal devices (PLCs), their synthesis, and applications in various liquid crystal devices (LCs) and displays. • Reviews the state-of-art of materials and technologies to manufacture hybrid white light-emitting diodes based on inorganic light sources and organic wavelength converters.

Organic Light-Emitting Devices

Organic Light-Emitting Devices
Author : Joseph Shinar
Publisher : Springer Science & Business Media
Release Date : 2013-03-20
Category : Technology & Engineering
Total pages :309
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Although it has long been possible to make organic materials emit light, it has only recently become possible to do so at the level and with the efficiency and control necessary to make the materials a useful basis for illumination in any but the most specialized uses. This book surveys the current status of the field.

Advanced Nanomaterials for Solar Cells and Light Emitting Diodes

Advanced Nanomaterials for Solar Cells and Light Emitting Diodes
Author : Feng Gao
Publisher : Elsevier
Release Date : 2019-04-15
Category : Technology & Engineering
Total pages :500
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Advanced Nanomaterials for Solar Cells and Light Emitting Diodes discusses the importance of nanomaterials as the active layers in solar cells and light emitting diodes (LEDs), along with the progress of nanomaterials as the electron and hole transporting layers. Specifically, the book reviews the use of nano-morphology of polymers, small molecules, and the organic-inorganic perovskites as the active layers in solar cells and LEDs. The design, fabrication and properties of metal-oxide-based nano-structures as electron and hole transporting layers are also reviewed. In addition, the development of plasmonic nanomaterials for solar cells and LEDs is discussed. Each topic in this book includes an overview of the materials system from principles to process. The advantages, disadvantages and related methodologies are highlighted. The book includes applications based on materials and emphasize how to improve the performance of solar cells and LEDs by the materials design, with a focus on nanomaterials. Provides latest research on nanostructured materials including small molecules, polymers, organic-inorganic perovskites, and many other relevant materials systems for solar cells and LEDs Addresses each promising materials system from principles to process, detailing the advantages and disadvantages of the most relevant methods of processing and fabrication Looks ahead to most likely techniques to improve performance of solar cells and light emitting diodes

Materials for Solid State Lighting and Displays

Materials for Solid State Lighting and Displays
Author : Adrian Kitai
Publisher : John Wiley & Sons
Release Date : 2017-03-06
Category : Science
Total pages :384
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Cover -- Title Page -- Copyright -- Contents -- List of Contributors -- Series Preface -- Preface -- Acknowledgments -- About the Editor -- Chapter 1 Principles of Solid State Luminescence -- 1.1 Introduction to Radiation from an Accelerating Charge -- 1.2 Radiation from an Oscillating Dipole -- 1.3 Quantum Description of an Electron during a Radiation Event -- 1.4 The Exciton -- 1.5 Two-Electron Atoms -- 1.6 Molecular Excitons -- 1.7 Band-to-Band Transitions -- 1.8 Photometric Units -- 1.9 The Light Emitting Diode -- References -- Chapter 2 Quantum Dots for Displays and Solid State Lighting -- 2.1 Introduction -- 2.2 Nanostructured Materials -- 2.3 Quantum Dots -- 2.3.1 History of Quantum Dots -- 2.3.2 Structure and Properties Relationship -- 2.3.3 Quantum Confinement Effects on Band Gap -- 2.4 Relaxation Process of Excitons -- 2.4.1 Radiative Relaxation -- 2.4.2 Nonradiative Relaxation Process -- 2.5 Blinking Effect -- 2.6 Surface Passivation -- 2.6.1 Organically Capped QDs -- 2.6.2 Inorganically Passivated QDs -- 2.7 Synthesis Processes -- 2.7.1 Top-Down Synthesis -- 2.7.2 Bottom-Up Approach -- 2.8 Optical Properties and Applications -- 2.8.1 Displays -- 2.8.2 Solid State Lighting -- 2.8.3 Biological Applications -- 2.9 Perspective -- Acknowledgments -- References -- Chapter 3 Color Conversion Phosphors for Light Emitting Diodes -- 3.1 Introduction -- 3.2 Disadvantages of Using LEDs Without Color Conversion Phosphors -- 3.3 Phosphors for Converting the Color of Light Emitted by LEDs -- 3.3.1 General Considerations -- 3.3.2 Requirements of Color Conversion Phosphors -- 3.3.3 Commonly Used Activators in Color Conversion Phosphors -- 3.3.4 Strategies for Generating White Light from LEDs -- 3.3.5 Outstanding Problems with Color Conversion Phosphors for LEDs