Organic electroluminescent device having a hole conductor as an emitting layer

Adachi, Chihaya; Tsutsui, Tetsuo; Saito, Shōgo

doi:10.1063/1.101586

Cited by 568 publications

(243 citation statements)

References 5 publications

Supporting

Mentioning

238

Contrasting

Unclassified

Order By: Relevance

“…2 Polymer-based organic LED's were discovered by Burroughes et al some years later and have stimulated a new wave of interest in this field. 3 Polymer devices have now been demonstrated with internal quantum efficiencies of up to 4%, 4 operating voltages below 5 V, emission wavelengths throughout the visible spectrum, [3][4][5][6][7] and operating lifetimes beyond 1200 h. 8 The simplest organic LED's consist of a thin, light-emitting organic film sandwiched between two metal electrodes.…”

Section: Introductionmentioning

confidence: 99%

Solid-state-concentration effects on the optical absorption and emission of poly(p-phenylene vinylene)-related materials

et al. 1996

View full text Add to dashboard Cite

We present measurements of the optical absorption and emission properties of poly(p-phenylene vinylene͒ ͑PPV͒ -related materials focusing on the differences between molecules isolated by dispersion in an inert host and concentrated molecular films. Optical absorption spectra, photoluminescence ͑PL͒ spectra, PL efficiency, and time-resolved PL spectra of dilute blends of PPV oligomers with 2-5 phenylene-phenyl rings are compared with those of dense oligomer and polymer films. In dilute oligomer-poly͑methyl methacrylate͒ ͑PMMA͒ blends with high PL efficiency, the PL decay is exponential, independent of both temperature and oligomer length. This implies that the fundamental radiative lifetime of PPV oligomers is essentially independent of oligomer length. Concentrated spin-cast oligomer films and polymers have a faster and strongly temperaturedependent PL decay that approaches that of the dilute oligomer results at low temperature. The differences in PL decay correspond to changes in PL efficiency. The efficiency of the oligomer-PMMA blend is high and only weakly temperature dependent, whereas that of concentrated films is lower and strongly temperature dependent, decreasing by more than a factor of 3 from 10 to 350 K. The quenching of the PL efficiency in concentrated films is due to migration to extrinsic, impurity related centers as opposed to an intrinsic intermolecular recombination process. The PL spectrum of a dilute oligomer blend redshifts substantially, both as the excitation energy is decreased and as the emission time increases. This spectral redshift is due to disorderinduced site-to-site variation and not to diffusion to lower-energy sites. In contrast, no spectral shift with excitation energy or emission time was observed for dense oligomer films. ͓S0163-1829͑96͒03132-3͔

show abstract

Section: Introductionmentioning

confidence: 99%

Solid-state-concentration effects on the optical absorption and emission of poly(p-phenylene vinylene)-related materials

et al. 1996

View full text Add to dashboard Cite

show abstract

“…At present, stimulated emission behavior, including amplified spontaneous emission (ASE), is observed in organic lasing dyes [4][5][6][7][8][9][10], yet the stimulated emission is eventually hampered by the low-efficiency energy transfer mechanism and concomitant singlet-triplet annihilation, which prohibits a sustained population inversion [11,12]. In addition, the low efficiency problem caused by annihilation can be resolved by adding an auxiliary film-forming polymer to dilute the laser dye mixed solutions [13,14]. On the other hand, from the perspective of organic materials, the less overlap between absorption spectra and photoluminescence (PL) spectra will help reduce the self-absorption attenuation of this material, ensuring the stimulated lasing with low threshold.…”

Section: Introductionmentioning

confidence: 99%

The energy transfer mechanism of a photoexcited and electroluminescent organic hybrid thin film of blue, green, and red laser dyes

Li¹,

Zhang²,

Zheng³

et al. 2016

Nano Online

View full text Add to dashboard Cite

Though optically pumped lasing has been realized for years, electrically pumped lasing has not yet been achieved in organic semiconductor devices. In order to make a better understanding of the laser mechanisms of the organic materials, we prepared organic thin films consisting of three efficient laser dyes of a blue emitter, 4″,4″′-N,vinyl]benzene (DSB), and a red emitter, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidy-l-9-enyl)-4H-pyran (DCJTB) with different doping concentrations for the first time to investigate the cascade energy transfer process. The energy transfer schemes in the co-doped thin films in photoluminescence and electroluminescence have been investigated. The results indicated that the DSB molecules acted as a bridge to deliver energy more effectively from the host (BN) to the guest (DCJTB). Meanwhile, the maximum current efficiency (C E ) and power efficiency (P E ) of the organic light-emitting devices (OLEDs) with the emitting layer of lower doping concentration were 13.5 cd/A and 14.1 lm/W, respectively.

show abstract

“…Since the first reports of organic electroluminescent (EL) devices in the late 1980s [1][2][3][4], there has been significant interest in the field of organic light-emitting diodes (OLEDs) driven by questions related to fundamental research as well as by proposed industrial applications. An example is solid-state lightning [5][6][7], which holds great promise as an energy-efficient light source.…”

Section: Introductionmentioning

confidence: 99%

Non-doped, blue-emitting, color-stable, organic light-emitting diode based on 2,2′:6′,2″-ternaphthalene

et al. 2014

View full text Add to dashboard Cite

A novel non-doped blue-emitting material, 2,2 0 :6 0 ,2 00 -ternaphthalene (NNN), which is based on three naphthalene units forming a rodlike molecule, has been synthesized and characterized. Organic light-emitting diodes based on NNN as emitter exhibit blue emission with Commission Internationale de l'Eclairage color coordinates of x = 0.18 and y = 0.11. In addition, the morphology and crystallographic structure of the NNN thin films has been investigated. NNN deposited on poly[3,4-(ethylenedioxy) thiophene]:poly (styrene sulfonate) on Indium Tin Oxide-covered glass forms crystalline structures of high crystallographic quality. The molecules are aligned almost perpendicular to the substrate surface and exhibit a tilt angle of 23 .

show abstract

Organic electroluminescent device having a hole conductor as an emitting layer

Cited by 568 publications

References 5 publications

Solid-state-concentration effects on the optical absorption and emission of poly(p-phenylene vinylene)-related materials

Solid-state-concentration effects on the optical absorption and emission of poly(p-phenylene vinylene)-related materials

The energy transfer mechanism of a photoexcited and electroluminescent organic hybrid thin film of blue, green, and red laser dyes

Non-doped, blue-emitting, color-stable, organic light-emitting diode based on 2,2′:6′,2″-ternaphthalene

Contact Info

Product

Resources

About