Browse
Submit Data
Databases
API
Help

Dataset Information

20 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Evolution of pure hydrocarbon hosts: simpler structure, higher performance and universal application in RGB phosphorescent organic light-emitting diodes.

ABSTRACT: In the field of phosphorescent organic light-emitting diodes (PhOLEDs), designing high-efficiency universal host materials for red, green and blue (RGB) phosphors has been quite a challenge. To date, most of the high-efficiency universal hosts reported incorporate heteroatoms, which have a crucial role in the device performance. However, the introduction of different kinds of heterocycles increases the design complexity and cost of the target material and also creates potential instability in the device performance. In this work, we show that pure aromatic hydrocarbon hosts designed with the 9,9'-spirobifluorene scaffold are high-efficiency and versatile hosts for PhOLEDs. With external quantum efficiencies of 27.3%, 26.0% and 27.1% for RGB PhOLEDs respectively, this work not only reports the first examples of high-efficiency pure hydrocarbon materials used as hosts in RGB PhOLEDs but also the highest performance reported to date for a universal host (including heteroatom-based hosts). This work shows that the PHC design strategy is promising for the future development of the OLED industry as a high-performance and low-cost option.

SUBMITTER: Wang Q

PROVIDER: S-EPMC8159222 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Pure Hydrocarbon Materials as Highly Efficient Host for White Phosphorescent Organic Light-Emitting Diodes: A New Molecular Design Approach.

Project description:To date, all efficient host materials reported for phosphorescent OLEDs (PhOLEDs) are constructed with heteroatoms, which have a crucial role in the device performance. However, it has been shown in recent years that the heteroatoms not only increase the design complexity but can also be involved in the instability of the PhOLED, which is nowadays the most important obstacle to overcome. Herein, we design pure aromatic hydrocarbon materials (PHC) as very efficient hosts in high-performance white and blue PhOLEDs. With EQE of 27.7 %, the PHC-based white PhOLEDs display similar efficiency as the best reported with heteroatom-based hosts. Incorporated as a host in a blue PhOLED, which are still the weakest links of the technology, a very high EQE of 25.6 % is reached, surpassing, for the first time, the barrier of 25 % for a PHC and FIrpic blue emitter. This performance shows that the PHC strategy represents an effective alternative for the future development of the OLED industry.

| S-EPMC9540750 | biostudies-literature

Preferential Orientation of Tetrahedral Silicon-Based Hosts in Phosphorescent Organic Light-Emitting Diodes.

Project description:Vacuum-processed diphenylbis(3-(pyridine-2-yl)phenyl)silane (2PTPS), diphenylbis(3-(pyridine-3-yl)phenyl)silane (3PTPS), and diphenylbis(3-(pyridine-4-yl)phenyl)silane (4PTPS) have been used as electron-transporting host materials combined with tris(4-carbazoyl-9-ylphenyl)amine (TCTA) as the hole-transporting host, which induce balanced charge carrier transport for high-efficiency phosphorescent organic light-emitting diodes. The 4PTPS-based organic light-emitting diodes with tris[2-phenylpyridinato-C 2,N]iridium(III) [Ir(ppy)3] dopant showed highest current efficiency and external quantum efficiency of 53.54 cd/A and 15.61%, compared to 2PTPS (40.75 cd/A, 11.84%) and 3PTPS (29.35 cd/A, 8.54%). These results were attributed to the well-aligned structure with preferential horizontal orientation of the emitting material layer by the diffraction intensity distribution as a function of azimuthal angle in two-dimensional grazing incidence X-ray diffraction analysis. The molecular orientation of TCTA:4PTPS material with a narrow azimuthal intensity distribution had better priority to the horizontal direction than the other TCTA:2PTPS and TCTA:3PTPS materials, which is related to the charge transport as well as the device efficiency. We found that the preferential horizontal orientation of the co-host material with a balanced charge carrier was not affected by Ir(ppy)3 dopant with a homoleptic structure and bis-[2-(4,6-difluorophenyl)pyridinato-N,C 2](picolinato)iridium [Firpic] dopant with a heteroleptic structure in the co-host/dopant system.

| S-EPMC6644814 | biostudies-literature

<i>De novo</i> design of D-σ-A molecules as universal hosts for monochrome and white phosphorescent organic light-emitting diodes.

Project description:Two novel D-σ-A host materials 11,11-bis(9-phenyl-9H-carbazol-3-yl)-11H-benzo[4,5]imidazo[1,2-a]indole (BII-BCz) and 4,4'-(11H-benzo[4,5]imidazo[1,2-a]indole-11,11-diyl)bis(N,N-diphenylaniline) (BII-TPA) are synthesized by using the sp3 carbon attached to a newly designed 11H-benzo[4,5]imidazo[1,2-a]indole building block to link two electron-donating groups. The resulting materials feature high triplet energy levels, good thermal properties and suitable photophysical properties as universal hosts for full-color phosphorescent organic light-emitting diodes (OLEDs). Both BII-BCz and BII-TPA reveal excellent performances in blue, green, yellow, orange and red phosphorescent OLEDs with the same device structure. The employment of the new D-σ-A materials as single hosts in white OLEDs with a simple device structure allows us to achieve state-of-the-art performances. A single-emissive-layer white device based on BII-BCz demonstrates the highest performance with an external quantum efficiency up to 28.2% at 1000 cd m-2. Furthermore, this device displays extremely stable emission spectra, with a ΔCIE of only (0.009, 0.005) from 1000 to 10 000 cd m-2.

| S-EPMC5935058 | biostudies-literature

Vacuum nanohole array embedded phosphorescent organic light emitting diodes.

Project description:Light extraction from organic light-emitting diodes that utilize phosphorescent materials has an internal efficiency of 100% but is limited by an external quantum efficiency (EQE) of 30%. In this study, extremely high-efficiency organic light emitting diodes (OLEDs) with an EQE of greater than 50% and low roll-off were produced by inserting a vacuum nanohole array (VNHA) into phosphorescent OLEDs (PhOLEDs). The resultant extraction enhancement was quantified in terms of EQE by comparing experimentally measured results with those produced from optical modeling analysis, which assumes the near-perfect electric characteristics of the device. A comparison of the experimental data and optical modeling results indicated that the VNHA extracts the entire waveguide loss into the air. The EQE obtained in this study is the highest value obtained to date for bottom-emitting OLEDs.

| S-EPMC4346830 | biostudies-other

Effects of Substitution Position of Carbazole-Dibenzofuran Based High Triplet Energy Hosts to Device Stability of Blue Phosphorescent Organic Light-Emitting Diodes.

Project description:High triplet energy hosts were developed through the modification of the substitution position of carbazole units. Two carbazole-dibenzofuran-derived compounds, 9,9'-(dibenzo[b,d]furan-2,6-diyl)bis(9H-carbazole) (26CzDBF) and 4,6-di(9H-carbazol-9-yl)dibenzo[b,d]furan (46CzDBF), were synthesized for achieving high triplet energy hosts. In comparison with the reported hole transport type host, 2,8-di(9H-carbazol-9-yl)dibenzo[b,d]furan (28CzDBF), 26CzDBF and 46CzDBF maintained high triplet energy over 2.95 eV. The device performances of the hosts were evaluated with electron transport type host, 2-phenyl-4, 6-bis(3-(triphenylsilyl)phenyl)-1,3,5-triazine (mSiTrz), to comprise a mixed host system. The deep blue phosphorescent device of 26CzDBF:mSiTrz with [[5-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]bis[[6-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]iridium (Ir(cb)3) dopant exhibited high external quantum efficiency of 22.9% with a color coordinate of (0.14, 0.16) and device lifetime of 1400 h at 100 cd m-2. The device lifetime was extended by 75% compared to the device lifetime of 28CzDBF:mSiTrz (800 h). These results demonstrated that the asymmetric and symmetric substitution of carbazole can make differences in the device performance of the carbazole- and dibenzofuran- derived hosts.

| S-EPMC8126063 | biostudies-literature

Efficient white phosphorescent organic light-emitting diodes using ultrathin emissive layers (<1?nm).

Project description:In this paper, efficient phosphorescent white organic light-emitting diodes (WOLEDs) were fabricated based on ultrathin doping-free emissive layers and mixed bipolar interlayers. The energy transfer processes were proved via the research of WOLEDs with different interlayer thicknesses and transient photoluminescence lifetime. WOLEDs with optimized thickness of doping-free emissive layers show maximum current efficiency of 47.8?cd/A and 44.9?cd/A for three-colors and four-colors WOLEDs, respectively. The Commission Internationale de L'Eclairage coordinates shows a very slight variation of (?±?0.02,?±?0.02) from 5793?cd/m2 to 11370?cd/m2 for three-colors WOLEDs and from 3038?cd/m2 to 13720?cd/m2 for four-colors WOLEDs, respectively. The stability of the spectra is attributed to the stable and sequential energy transfer among the various dyes. The color temperature of four-colors WOLEDs can be obtained from 2659 to 6636 by adjusting the thickness of ultrathin emissive layer.

| S-EPMC5904154 | biostudies-literature

Hot excited state management for long-lived blue phosphorescent organic light-emitting diodes.

Project description:Since their introduction over 15 years ago, the operational lifetime of blue phosphorescent organic light-emitting diodes (PHOLEDs) has remained insufficient for their practical use in displays and lighting. Their short lifetime results from annihilation between high-energy excited states, producing energetically hot states (>6.0?eV) that lead to molecular dissociation. Here we introduce a strategy to avoid dissociative reactions by including a molecular hot excited state manager within the device emission layer. Hot excited states transfer to the manager and rapidly thermalize before damage is induced on the dopant or host. As a consequence, the managed blue PHOLED attains T80=334±5?h (time to 80% of the 1,000?cd?m-2 initial luminance) with a chromaticity coordinate of (0.16, 0.31), corresponding to 3.6±0.1 times improvement in a lifetime compared to conventional, unmanaged devices. To our knowledge, this significant improvement results in the longest lifetime for such a blue PHOLED.

| S-EPMC5460033 | biostudies-literature

Phosphine Sulfide-Based Bipolar Host Materials for Blue Phosphorescent Organic Light-Emitting Diodes.

Project description:Three phosphine sulfide-based bipolar host materials, vizCzPhPS, DCzPhPS, and TCzPhPS, were facilely prepared through a one-pot synthesis in excellent yields. The developed hosts exhibit superior thermal stabilities with the decomposition temperatures (Td) all exceeding 350 °C and the melting temperatures (Tm) over 200 °C. In addition, their triplet energy (ET) levels are estimated to be higher than 3.0 eV, illustrating that they are applicable to serve as hosts for blue phosphorescent organic light-emitting diodes (PhOLEDs). The maxima luminance, current efficiency (CE), power efficiency (PE), and external quantum efficiency (EQE) of 17,223 cd m-2, 36.7 cd A-1, 37.5 lm W-1, and 17.5% are achieved for the blue PhOLEDs hosted by CzPhPS. The PhOLEDs based on DCzPhPS and TCzPhPS show inferior device performance than that of CzPhPS, which might be ascribed to the deteriorated charge transporting balance as the increased number of the constructed carbazole units in DCzPhPS and TCzPhPS molecules would enhance the hole-transporting ability of the devices to a large extent. Our study demonstrates that the bipolar hosts derived from phosphine sulfide have enormous potential applications in blue PhOLEDs, and the quantity of donors should be well controlled to exploit highly efficient phosphine sulfide-based hosts.

| S-EPMC8271492 | biostudies-literature

Pure exciplex-based white organic light-emitting diodes with imitation daylight emissions.

Project description:An exciplex could be formed by blending a selected hole-transporting material (HTM)/electron-transporting material (ETM) pair, and the corresponding energy band gap is roughly determined by the energy difference between the lowest unoccupied molecular orbital (LUMO) of the ETM and the highest occupied molecular orbital (HOMO) of the HTM. In this study, three HTM/ETM combinations are adopted to generate blue, green, and red exciplexes, allowing us to design precise device architectures for the fabrication of exciplex-based white OLEDs (WOLEDs) with daylight-like emissions. The CIE coordinates of this WOLED varied close to the Planckian locus as the biases increase, with a high color rendering index of about 96. This high performance suggests this exciplex-based WOLED can provide high-quality white-light illumination. Photoluminance and lifetime measurements of the exciplex behavior of the HTM/ETM combinations indicate that the HTM and ETM selected should possess higher triplet energy bandgaps than those of their corresponding exciplex to avoid energy loss.

| S-EPMC9085475 | biostudies-literature

84% efficiency improvement in all-inorganic perovskite light-emitting diodes assisted by a phosphorescent material.

Project description:A novel mixed perovskite emitter layer is applied to design all-inorganic cesium lead halide perovskite light-emitting diodes (PeLEDs) with high electroluminescence (EL) performance, by combining CsPbBr3 with iridium(iii)bis[2-(4',6'-difluorophenyl)pyridinato-N,C2']-picolinate (FIrpic), where FIrpic is a phosphorescent material with very high internal quantum efficiency (IQE) approaching 100%. The CsPbBr3:FIrpic PeLEDs show a maximum luminance of 5486 cd m-2, and an external quantum efficiency of 0.47%, which are 1.84 and 1.76 times that of neat CsPbBr3 PeLEDs, respectively. It is found that FIrpic molecules as an assistant dopant can efficiently transmit energy from the excitons of FIrpic to the excited state of the CsPbBr3 emitter via a Förster energy transfer process, leading to enhanced EL efficiency in the CsPbBr3:FIrpic PeLEDs.

| S-EPMC9080124 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data