Novel Ambipolar Orthogonal Donor–Acceptor Host for Blue Organic Light Emitting Diodes

Leung, M.‐k.; Hsieh, Yu-Hsuan; Kuo, Ting-Yi; Chou, Pi‐Tai; Lee, Jiun-Haw; Chiu, Tien‐Lung; Chen, Hsin-Jen

doi:10.1021/ol402001v

Cited by 38 publications

(22 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Since 3D H‐bonding networks assisting pyridine‐like CH⋯N bonding are key interactions that facilitate carrier tunneling and migration, combined with the intrinsic and admirable charge‐transport properties of the carbazole and triazole building blocks, evaluating the carrier‐transport properties of PCZTZ is necessary and meaningful. Due to the easy preparation and vacuum deposition of PCZTZ, we measured the carrier mobility of PCZTZ utilizing a time‐of‐flight (TOF) technique that consumed a large amount of sample (see Figure S8, Supporting Information).…”

Section: Resultsmentioning

confidence: 99%

“…Additionally, the still twisted molecular backbone will benefit from the intrinsically distorted 9‐phenylcarbazole unit, and the three mutual repulsive phenyl groups on the triazole ring could render molecular aggregates with weak π–π interactions and a wide HOMO–LUMO gap. Moreover, aromatic N‐heterocycles with exposed sp 2 ‐N electron lone pairs could be conducive to electron transport through strong intermolecular CH⋯N interactions . Therefore, appropriate carbazole–triazole hybrids are expected to exhibit strong NUV fluorescence and commendable ambipolar charge‐transport abilities, and consequently, highly efficient NUV EL emitters could be developed.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Highly Efficient Nondoped Near‐Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility

Xue

Qiu

Ying

et al. 2017

Advanced Optical Materials

View full text Add to dashboard Cite

Organic light-emitting diodes (OLEDs) with conjugated organic molecules as fluorescent emitters continue to attract significant interest because they have flexible molecular structures and are easy to prepare and abundant resources of organic fluorophores. [1] To date, while red, green, and even ordinary blue emitters with desirable electroluminescence (EL) efficiencies have been achieved, highly efficient organic emitters exhibiting the near-ultraviolet (NUV) EL (such as with emission peak at Low charge injection and unbalanced carrier transport are unfavorable factors for highly efficient near-ultraviolet (NUV) electroluminescence (EL) emitters. The construction of weak donor-and acceptor-containing fluorophores has been utilized as a common solution to these issues. Few fluorescent emitters simultaneously exhibiting NUV emission and high/balanced charge-transport properties have been reported. Herein, a new 1D donor-π-acceptor molecule 9-(4′-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)-[1,1′-biphenyl]-4-yl)-9H-carbazole named PCZTZ consisting of 9-phenylcarbazole as a donor and 2,3,4-triphenyl-1,2,4-triazole as an acceptor with a biphenyl π-bridge is constructed. The backbone-twisted PCZTZ exhibits not only strong solid-state NUV fluorescence but also high and balanced hole and electron mobilities (both up to 10 −4 cm 2 V −1 s −1 ), benefiting from the 3D supramolecular H-bonding network containing strong CH⋯N interactions. Remarkably, a fabricated nondoped light-emitting diode (OLED) emits 408 nm bright NUV light with a maximal external quantum efficiency of 6.57% and Commission Internationale de L'Eclairage coordinates of (0.17, 0.07). Thus, this OLED is the most efficient NUV OLED reported thus far. These results provide a valuable strategy for the design of highly efficient NUV EL emitters by modulating the linking positions of carbazole and triazole on a biphenyl bridge.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Highly Efficient Nondoped Near‐Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility

Xue

Qiu

Ying

et al. 2017

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…In a way, they are similar to so-called ambipolar host molecules and often even contain similar building blocks, which are either arranged in a different way or used in different combinations in order to realize the large bandgap, which is needed to accommodate dopant molecules. [50][51][52][53][54][55] In both hosts and TADF emitters, donor moieties are electron-rich functional units that have a rather deep HOMO, which allow them to be oxidized easily and partake in the transport of holes. Contrarily, acceptor moieties are electron-deficient functional units with a deep LUMO.…”

Section: Molecular Design Principlesmentioning

confidence: 99%

Review of organic light-emitting diodes with thermally activated delayed fluorescence emitters for energy-efficient sustainable light sources and displays

Volz

2016

J. Photon. Energy

View full text Add to dashboard Cite

Daniel Volz, "Review of organic light-emitting diodes with thermally activated delayed fluorescence emitters for energy-efficient sustainable light sources and displays," J. Photon. Energy 6(2), 020901 (), doi: 10.1117/1.JPE.6.020901. Abstract. Thermally activated delayed fluorescence (TADF) is an emerging hot topic. Even though this photophysical mechanism itself has been described more than 50 years ago and optoelectronic devices with organic matter have been studied, improved, and even commercialized for decades now, the realization of the potential of TADF organic light-emitting diodes (OLEDs) happened only recently. TADF has been proven to be an attractive and very efficient alternative for phosphorescent materials, such as dopants in OLEDs, light-emitting electrochemical cells as well as potent emitters for chemiluminescence. In this review, the TADF concept is introduced in terms that are also understandable for nonchemists. The basic concepts behind this mechanism as well as state-of-the-art examples are discussed. In addition, the future economic impact, especially for the lighting and display market, is addressed here. We conclude that TADF materials are especially helpful to realize efficient, durable deep blue and white displays.

show abstract

“…[27] This work was carriedo ut with 1 (E T = 2.76 eV), which displayed promising performance for the first generation of new materials. [27] However,b ipolar molecules are, to date, the most promising candidates for high-efficiency PhOLEDs, [41][42][43][44][45][46][47][48][49] and the first generation of dihydroindenofluorenes 1 and 2 did not possess any hole-or electron-transporting functionalities. Herein, we wish to report an ew generation of high E T meta-substituted dihydroindenofluorenes that incorporate hole-and electron-transporting moieties.…”

Section: Introductionmentioning

confidence: 99%

Donor/Acceptor Dihydroindeno[1,2‐a]fluorene and Dihydroindeno[2,1‐b]fluorene: Towards New Families of Organic Semiconductors

Romain

Tondelier

Geffroy

et al. 2015

Chemistry A European J

View full text Add to dashboard Cite

New families of donor/acceptor semiconductors based on dihydroindeno[1,2-a]fluorene and dihydroindeno[2,1-b]fluorene are reported. Due to the spiro bridges, this new generation of dihydroindenofluorenes allows a spatial separation of HOMO and LUMO, which retains the high ET value of the dihydroindenofluorene backbone and excellent physical properties. This control of the electronic and physical properties has allowed a second generation of dihydroindeno[1,2-a]fluorene to be obtained with strongly enhanced performance in green and sky-blue phosphorescent organic light-emitting diodes (PhOLEDs) relative to the first generation of materials. To date, this is the highest performance ever reported for a blue PhOLED by using a dihydroindenofluorene derivative. Through this structure-property relationship study, a remarkable difference of performance between syn and anti isomers has also been highlighted. This surprising behaviour has been attributed to the different symmetry of the two molecules, and highlights the importance of the geometry profiles in the design of host materials for PhOLEDs.

show abstract

Novel Ambipolar Orthogonal Donor–Acceptor Host for Blue Organic Light Emitting Diodes

Cited by 38 publications

References 41 publications

Highly Efficient Nondoped Near‐Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility

Highly Efficient Nondoped Near‐Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility

Review of organic light-emitting diodes with thermally activated delayed fluorescence emitters for energy-efficient sustainable light sources and displays

Donor/Acceptor Dihydroindeno[1,2‐a]fluorene and Dihydroindeno[2,1‐b]fluorene: Towards New Families of Organic Semiconductors

Contact Info

Product

Resources

About