High‐Performance Orange–Red Organic Light‐Emitting Diodes with External Quantum Efficiencies Reaching 33.5% based on Carbonyl‐Containing Delayed Fluorescence Molecules DOI Creative Commons
Ruming Jiang, Xing Wu, Hao Liu

et al.

Advanced Science, Journal Year: 2021, Volume and Issue: 9(3)

Published: Dec. 19, 2021

Abstract Developing orange to red purely organic luminescent materials having external quantum efficiencies ( η ext s) exceeding 30% is challenging because it generally requires strong intramolecular charge transfer, efficient reverse intersystem crossing (RISC), high photoluminescence yield Φ PL ), and large optical outcoupling efficiency out ) simultaneously. Herein, by introducing benzoyl dibenzo[ a , c ]phenazine acceptor, stronger electron ]phenazin‐11‐yl(phenyl)methanone, created employed for constructing orange–red delayed fluorescence molecules with various acridine‐based donors. The incorporation of leads red‐shifted accelerated RISC, reduced lifetimes, increased s, the adoption spiro‐structured acridine donors promotes horizontal dipole orientation thus renders s. Consequently, state‐of‐the‐art light‐emitting diodes are achieved, providing record‐high electroluminescence (EL) 33.5%, 95.3 cd A −1 93.5 lm W ‒1 . By referring control molecule without benzoyl, demonstrated that presence can exert significant positive effect over improving enhancing EL efficiencies, which be feasible design robust materials.

Language: Английский

Intramolecular Repulsive Interactions Enable High Efficiency of NIR-II Aggregation-Induced Emission Luminogens for High-Contrast Glioblastoma Imaging DOI

Fulong Ma,

Zhiyuan Gao, Qian Jia

et al.

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 3, 2025

Strategies to acquire high-efficiency luminogens that emit in the second near-infrared (NIR-II, 1000-1700 nm) range are still rare due impediment of energy gap law. Herein, a feasible strategy is pioneered by installing large-volume encumbrances confined space intensify repulsive interactions arising from overlapping electron densities. The experimental results, including smaller coordinate displacement, reduced reorganization energy, and suppressed internal conversion, demonstrate assist inhibition radiationless deactivation. Meanwhile, configuration hybridization form donor units transformed along with interactions, bringing about improved oscillator strength. A 3.8-fold higher luminescence efficiency realized via synergistic effect. Furthermore, endow NIR-II fluorophores highly twisted conformation, superior AIE activity, cascaded improvement fluorescence emission isolated molecules aggregates. By utilizing brain-targeting peptide functionalize nanoparticles, accurate detection high-contrast imaging orthotopic glioblastoma realized. This work not only explores fundamental principle handle intractable law but also provides potential applications bioimaging detection.

Language: Английский

Citations

1
Thermally activated delayed fluorescence enhanced by macrocyclization DOI Creative Commons
Shuo Li, Chenghao Zhu, Lijun Mao

et al.

Science China Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 3, 2025

Language: Английский

Citations

1
Molecular Design Strategy for Orange Red Thermally Activated Delayed Fluorescence Emitters in Organic Light‐Emitting Diodes (OLEDs) DOI
Kenkera Rayappa Naveen,

Keshavananda Prabhu,

Ramanaskanda Braveenth

et al.

Chemistry - A European Journal, Journal Year: 2021, Volume and Issue: 28(12)

Published: Dec. 17, 2021

Pure organic molecules based thermally activated delayed fluorescence (TADF) emitters have been successfully developed in recent years for their propitious application highly efficient light emitting diodes (OLEDs). In the case of orange red emitters, non-radiative process is known to be a serious issue due its lower lying singlet energy level. However, studies indicate that there are tremendous efforts put develop TADF emitters. addition, external quantum efficiency (EQE) heteroaromatic OLEDs surpassed 30 %. Such type showed wide emission spectra; therefore, more attention being paid along with good color purity. Herein, progress on molecular structures, such as cyanobenzene, heteroaromatic, naphthalimide, and boron-based acceptors, reviewed. Further, our insight these acceptors has provided by photophysical device performances. Future perspectives real practical applications discussed.

Language: Английский

Citations

51
Rigid Bridge‐Confined Double‐Decker Platinum(II) Complexes Towards High‐Performance Red and Near‐Infrared Electroluminescence DOI
Youming Zhang, Jingsheng Miao,

Jinfan Xiong

et al.

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(1)

Published: Nov. 4, 2021

A molecular design to high-performance red and near-infrared (NIR) organic light-emitting diodes (OLEDs) emitters remains demanding. Herein a series of dinuclear platinum(II) complexes featuring strong intramolecular Pt⋅⋅⋅Pt π-π interactions has been developed by using N-deprotonated α-carboline as bridging ligand. The in doped thin films exhibit efficient NIR emission from short-lived (τ=0.9-2.1 μs) triplet metal-metal-to-ligand charge transfer (3 MMLCT) excited states. Red OLEDs demonstrate high maximum external quantum efficiencies (EQEs) up 23.3 % among the best PtII -complex-doped devices. EQE 15.0 radiance 285 W sr-1 m-2 for (λEL =725 nm) are unprecedented devices based on discrete emitters. Both show very small efficiency roll-off at brightness. Appealing operational lifetimes have also revealed This work sheds light potential metallophilicity long-wavelength electroluminescence.

Language: Английский

Citations

49
High‐Performance Orange–Red Organic Light‐Emitting Diodes with External Quantum Efficiencies Reaching 33.5% based on Carbonyl‐Containing Delayed Fluorescence Molecules DOI Creative Commons
Ruming Jiang, Xing Wu, Hao Liu

et al.

Advanced Science, Journal Year: 2021, Volume and Issue: 9(3)

Published: Dec. 19, 2021

Abstract Developing orange to red purely organic luminescent materials having external quantum efficiencies ( η ext s) exceeding 30% is challenging because it generally requires strong intramolecular charge transfer, efficient reverse intersystem crossing (RISC), high photoluminescence yield Φ PL ), and large optical outcoupling efficiency out ) simultaneously. Herein, by introducing benzoyl dibenzo[ a , c ]phenazine acceptor, stronger electron ]phenazin‐11‐yl(phenyl)methanone, created employed for constructing orange–red delayed fluorescence molecules with various acridine‐based donors. The incorporation of leads red‐shifted accelerated RISC, reduced lifetimes, increased s, the adoption spiro‐structured acridine donors promotes horizontal dipole orientation thus renders s. Consequently, state‐of‐the‐art light‐emitting diodes are achieved, providing record‐high electroluminescence (EL) 33.5%, 95.3 cd A −1 93.5 lm W ‒1 . By referring control molecule without benzoyl, demonstrated that presence can exert significant positive effect over improving enhancing EL efficiencies, which be feasible design robust materials.

Language: Английский

Citations

43