AI Article Synopsis
Article Abstract
Photon-upconversion in organic molecular systems is one of the promising technologies for future energy harvesting systems because these systems can generate excitons that possess higher energy than excitation energy. The photon-upconversion caused by absorbing ambient heat as additional energy is particularly interesting because it could ideally provide a light-driving cooling system. However, only a few organic molecular systems have been reported. Here, we report the anti-Stokes photoluminescence (ASPL) derived from hot-band absorption in a series of multi-resonance-type thermally-activated delayed fluorescence (MR-TADF) molecules. The MR-TADF molecules exhibited an anti-Stokes shift of approximately 0.1 eV with a high PL quantum yield in the solution state. The anti-Stokes shift corresponded well to the 1-0 vibration transition from the ground state to the excited singlet state, and we further evaluated a correlation between the activation energy for the ASPL intensity and the TADF process. Our demonstration underlines that MR-TADF molecules have become a novel class of ASPL materials for various future applications, such as light-driving cooling systems.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/anie.202312326 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enabling High-Performance Multi-Resonant TADF Emitters via Intramolecular Hydrogen Bond.
Chemistry
December 2024
Hebei Key Laboratory of Organic Functional Molecules, Hebei Technology Innovation Center for Energy Conversion Materials and Devices, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, PR China E-mail address.
Hydrogen bonds (HBs), prevalent strong interactions in organic compounds, can effectively constrain single bond rotation, leading to rigid planar configurations. This rigidity enhances emission efficiency and narrows the emission spectrum of luminescent materials. Recent advances have leveraged HBs to advance high-performance donor-acceptor thermally activated delayed fluorescence (TADF) materials.
View Article and Find Full Text PDFPendant engineering in multiple-resonance thermally activated delayed fluorescence to yield charge-transfer and locally excited-state characteristics.
Nanoscale
December 2024
Department of Chemistry, Dankook University, Cheonan 31116, South Korea.
Article Synopsis
- Multiple-resonance thermally activated delayed fluorescence (MR-TADF) materials have narrow-spectrum features due to restricted molecular rotation, which could impact the design of organic light-emitting diodes (OLEDs).
- This study synthesized various MR-TADF materials with different pendant groups and analyzed their excited states, spin-orbit couplings, and efficiency in OLEDs.
- Results showed that the OLED using the neutral pendant (tDABNA-TP) achieved the highest external quantum efficiency (20.7%) and a significantly longer operating lifetime compared to those with donor and acceptor pendants.
Efficient and Stable Narrowband Pure-Red Light-Emitting Diodes with Electroluminescence Efficiencies Exceeding 43.
J Am Chem Soc
November 2024
Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
Advanced multiresonance-induced thermally activated delayed fluorescence (MR-TADF) materials exhibit exceptional promise for applications in state-of-the-art organic light-emitting diodes (OLEDs) owing to their unique narrowband emissions and high luminescent efficiencies. Despite substantial progress with blue and green MR-TADF materials, the development of pure-red MR-TADF emitters has lagged behind, thereby hindering the advancement toward high-performance ultrahigh-definition OLED displays. Here, we propose an effective approach for designing pure-red MR-TADF molecules based on the integration of secondary electron-donating units and π-skeleton extension into MR cores, which enables not only a redshift of narrowband emission but also an acceleration of reverse intersystem crossing (RISC) rate.
View Article and Find Full Text PDFSpiro-Carbon-Locking and Sulfur-Embedding Strategy for Constructing Deep-Red Organic Electroluminescent Emitter with High Efficiency.
Angew Chem Int Ed Engl
November 2024
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
The discovery of multiple resonance thermally activated delayed fluorescence (MR-TADF) materials with remarkable narrowband emission has opened a new avenue for the development of organic light-emitting diodes (OLEDs) with high color purity. However, the lack of construction strategies for purely red MR-TADF materials significantly impedes their application in full-color high-definition displays. Herein, we propose a unique and handy approach of spiro-carbon-locking and sulfur-embedding strategy to modify the parent MR-TADF framework, resulting in a red MR-TADF emitter with high color purity.
View Article and Find Full Text PDFA perspective on next-generation hyperfluorescent organic light-emitting diodes.
Chem Sci
October 2024
Materials Research Centre, Indian Institute of Science Bangalore 560012 Karnataka India
Hyperfluorescence, also known as thermally activated delayed fluorescence (TADF) sensitized fluorescence, is known as a next-generation efficient and innovative process for high-performance organic light-emitting diodes (OLEDs). High external quantum efficiency (EQE) and good color purity are crucial parameters for display applications. Hyperfluorescent OLEDs (HF-OLEDs) take the lead in this respect as they utilize the advantages of both TADF emitters and fluorescent dopants, realizing high EQE with color saturation and long-term stability.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!