Stabilization of Blue Emitters with Thermally Activated Delayed Fluorescence by the Steric Effect: A Case Study by means of Magnetic Field Effects

2020 ◽  
Vol 14 (3) ◽  
Author(s):  
Chongguang Zhao ◽  
Fenggui Zhao ◽  
Kai Wang ◽  
Haomiao Yu ◽  
Tianyu Huang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Steric Effect ◽  
Delayed Fluorescence ◽  
Magnetic Field Effects ◽  
Thermally Activated Delayed Fluorescence ◽  
Thermally Activated ◽  
Field Effects ◽  
Blue Emitters

Extraordinary magnetic field effects mediated by spin-pair interaction and electron mobility in thermally activated delayed fluorescence-based OLEDs with quantum-well structure

2019 ◽  
Vol 7 (8) ◽  
pp. 2421-2429 ◽  
Author(s):  
Ruiheng Pan ◽  
Xiantong Tang ◽  
Yeqian Hu ◽  
Hongqiang Zhu ◽  
Jinqiu Deng ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Quantum Well ◽  
Pair Interaction ◽  
Delayed Fluorescence ◽  
Magnetic Field Effects ◽  
Thermally Activated Delayed Fluorescence ◽  
Light Emitting ◽  
Spin Pair ◽  
Thermally Activated ◽  
Field Effects

We fabricated quantum-well organic light-emitting diodes (QW-OLEDs) based on thermally activated delayed fluorescence (TADF) and measured their magnetic field effects curves over various magnetic field ranges.

scholarly journals Progress on Donor-Acceptor Type Thermally Activated Delayed Fluorescence Based Blue Emitters

2017 ◽  
Vol 37 (10) ◽  
pp. 2480 ◽  
Author(s):  
Jihua Tan ◽  
Yanping Huo ◽  
Ning Cai ◽  
Shaomin Ji ◽  
Zongzhi Li ◽  
...  
Keyword(s):  
Delayed Fluorescence ◽  
Thermally Activated Delayed Fluorescence ◽  
Thermally Activated ◽  
Donor Acceptor ◽  
Blue Emitters

Spin-pair state-induced exceptional magnetic field responses from a thermally activated delayed fluorescence-assisted fluorescent material doping system

2019 ◽  
Vol 21 (32) ◽  
pp. 17673-17686
Author(s):  
Yeqian Hu ◽  
Xiantong Tang ◽  
Ruiheng Pan ◽  
Jinqiu Deng ◽  
Hongqiang Zhu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Energy Transfer ◽  
Delayed Fluorescence ◽  
Thermally Activated Delayed Fluorescence ◽  
Spin Pair ◽  
Thermally Activated ◽  
Transfer Processes ◽  
System P ◽  
Complex Spin ◽  
Pair State

Some exceptional magnetic field responses reflect complex spin-pair states and energy transfer processes in thermally activated delayed fluorescence-assisted fluorescent OLEDs.

scholarly journals Efficient Deep-Blue Electroluminescence Employing Heptazine-Based Thermally Activated Delayed Fluorescence

Photonics ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 293
Author(s):  
Jie Li ◽  
Jincheng Zhang ◽  
Heqi Gong ◽  
Li Tao ◽  
Yanqing Wang ◽  
...  
Keyword(s):  
High Performance ◽  
Light Emitting Diode ◽  
Blue Emission ◽  
Delayed Fluorescence ◽  
Thermally Activated Delayed Fluorescence ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Thermally Activated ◽  
Deep Blue ◽  
Blue Emitters

We report an efficient deep-blue organic light-emitting diode (OLED) based on a heptazine-based thermally activated delayed fluorescent (TADF) emitter, 2,5,8-tris(diphenylamine)-tri-s-triazine (HAP-3DPA). The deep-blue-emitting compound, HAP-3DPA, was designed and synthesized by combining the relatively rigid electron-accepting heptazine core with three electron-donating diphenylamine units. Due to the rigid molecular structure and intramolecular charge transfer characteristics, HAP-3DPA in solid state presented a high photoluminescence quantum yield of 67.0% and obvious TADF nature with a short delayed fluorescent lifetime of 1.1 μs. Most importantly, an OLED incorporating HAP-3DPA exhibited deep-blue emission with Commission Internationale de l’Eclairage (CIE) coordinates of (0.16, 0.13), a peak luminance of 10,523 cd/m−2, and a rather high external quantum efficiency of 12.5% without any light out-coupling enhancement. This finding not only reports an efficient deep-blue TADF molecule, but also presents a feasible pathway to construct high-performance deep-blue emitters and devices based on the heptazine skeleton.

scholarly journals Magnetic field modulation of the delayed fluorescence yield in the photoionization reaction of N, N, N', N'-tetramethyl-p-phenylenediamine in water

1999 ◽  
Vol 1 (3) ◽  
pp. 177-181 ◽  
Author(s):  
Sameh Saad Ali ◽  
Günter Grampp ◽  
Stephan Landgraf ◽  
Michael Sacher
Keyword(s):  
Magnetic Field ◽  
Fluorescence Yield ◽  
Ion Pair ◽  
Delayed Fluorescence ◽  
Water Mixture ◽  
Magnetic Field Effects ◽  
Field Effects ◽  
Water Solvent ◽  
Solvent Cage ◽  
Field Modulation

External magnetic field effects on the recombination fluorescence (MARY effect) in the photoionization reaction ofN,N,N′,N′-Tetramethyl-p-phenylenediamine (TMPPD) in water and DMSO/water mixture are studied. Relatively large magnetic field effects (MFE),∼2–4%, on the fluorescence yield are observed in the extremely polar water solvent under magnetic fields as small as 3 mT. Such MFE is hardly expected in water due to instability and very fast escape of the solvated electron from the solvent cage. Enhancement in the signal-to-noise ratio and superior time resolution characterizing the technique of field modulation allowed the detection of a very short lived radical ion pair (about 1 ns). The observed MARY spectra illustrate that the singlet radical ion pair is more reactive than the triplet one.

Solvent Radical Anions in Irradiated Aliphatic Ketones and Esters as Observed Using Time-Resolved Magnetic Field Effects in the Recombination Fluorescence

2017 ◽  
Vol 231 (2) ◽  
Author(s):  
Vsevolod Borovkov ◽  
Andrey Taratayko ◽  
Alena Bessmertnykh ◽  
Victor Bagryansky ◽  
Yuriy Molin
Keyword(s):  
Magnetic Field ◽  
Ion Pairs ◽  
Delayed Fluorescence ◽  
Magnetic Field Effects ◽  
Time Resolved ◽  
Field Effects ◽  
Aliphatic Ketones ◽  
Stabilization Effect ◽  
Recombination Fluorescence ◽  
Hyperfine Couplings

AbstractIt has been found that addition of alcohols (~0.1 M) to some liquid ketones and esters results in well-pronounced oscillations in the decay of the delayed fluorescence intensity from irradiated solutions. The analysis of the time-resolved magnetic field effects (TR MFEs) in the recombination fluorescence has shown that these oscillations are a manifestation of singlet-triplet transitions in spin-correlated radical ion pairs (RIPs) created by irradiation. Comparison with literature data indicates that the transitions are due to hyperfine couplings (HFCs) in the solvent radical anion (RA), stabilized due to the presence of alcohol molecules. In acetone, this stabilization effect has been observed for methanol, ethanol, 2- propanol, and, to a smaller extent, for

Sign in / Sign up

Export Citation Format

Share Document