Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 159719 - 159719
Published: Jan. 1, 2025
Language: Английский
Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1624 - 1692
Published: Jan. 1, 2024
This review highlights organoboron-based multiple-resonance compounds’ synthetic strategies classified as one-pot borylation, one-shot and late-stage functionalisation, explores material structure–photophysical property correlations.
Language: Английский
Citations
124
Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(23), P. 12550 - 12560
Published: June 5, 2023
Multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising candidates for narrowband organic light-emitting diodes, but their electroluminescent performance is typically hindered by the slow reverse intersystem crossing rate (kRISC). Herein, we present an effective strategy to introduce a multichannel (RISC) pathway with large spin-orbit coupling orthogonally linking electron-donating unit MR framework. Through delicate manipulation of excited-state energy levels, additional intersegmental charge transfer triplet state could be "silently" induced without perturbing character lowest excited singlet state. The proof-of-concept emitter CzBN3 not only affords 23-fold increase kRISC compared its prototypical skeleton also realizes close-to-unity photoluminescence quantum yield, radiative constant, and very narrow emission spectrum. These merits enable high maximum external efficiency (EQEmax) up 37.1% alleviated roll-off in sensitizer-free device (EQE1000 = 30.4%), further boost (EQEmax/1000 42.3/34.1%) realized hyperfluorescent device. state-of-the-art validates superiority our molecular design strategy.
Language: Английский
Citations
122
Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(50)
Published: Aug. 7, 2023
Abstract Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters have drawn considerable attention because of their remarkable optoelectronic properties high emission efficiency and narrow profile, represent an active subject cutting‐edge research in the organic electroluminescence (EL). However, slow reverse intersystem crossing (RISC) rate MR‐TADF emitter caused by large energy gap (Δ E ST ) small spin‐orbit coupling (SOC) matrix elements between singlet triplet excited states limits further development EL devices. Currently, innovative molecular design strategies been developed including heavy atom integration, π‐extended MR framework metal perturbation, so on to improve RISC process for high‐performance Here, overview is presented recent progress with fast ( > 10 −5 s −1 ), particular design, properties, device performance light‐emitting diodes (OLEDs), which intends systematize knowledge this thriving highly efficient emitters. Finally, challenges future prospects materials are discussed comprehensively.
Language: Английский
Citations
97
Chemical Communications, Journal Year: 2023, Volume and Issue: 59(25), P. 3685 - 3702
Published: Jan. 1, 2023
The hunt for narrow-band emissive pure organic molecules capable of harvesting both singlet and triplet excitons light emission has garnered enormous attention to promote the advancement light-emitting diodes (OLEDs). Over past decade, thermally activated delayed fluorescence (TADF) materials based on donor (D)/acceptor (A) combinations have been researched OLEDs in wide color gamut (RGB) regions. However, due strong intramolecular charge-transfer (CT) state, they exhibit broad with full-width-at-half maximum (FWHM) > 70 nm, which deviates from being detrimental achieving high purity future high-end display electronics such as high-definition TVs ultra-high-definition (UHDTVs). Recently, new development sub-class TADF emitters called multi-resonant (MR-TADF) boron/nitrogen atoms attracted much interest ultra-high definition OLEDs. Consequently, MR-TADF are appeal their potentiality promising candidates fabricating high-efficient numerous advantages photoluminescence quantum yield (PLQY), unprecedented purity, narrow bandwidth (FWHM ≤ 40 nm). Until now many developed ultra-gamut regions different design concepts. most MR-TADF-OLEDs showed ruthless external efficiency (EQE) roll-off characteristics at brightness. Such EQE were derived mainly low reverse intersystem crossing (kRISC) rate values. This feature article primarily focuses strategies improve kRISC some supportive including extending charge delocalization, heavy atom introduction, multi-donor/acceptor utilization, a hyperfluorescence system approach. Furthermore, outlook prospects developments skeletons described.
Language: Английский
Citations
82
Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(25)
Published: March 8, 2023
Ultraviolet (UV, λ<400 nm) light is essential for various photochemical reactions, but its intensity in the solar spectrum very low, and sources that artificially generate high-energy UV are inefficient environmentally unfriendly. A solution to this problem photon upconversion (UC) from visible (vis, λ>400 light. Among several mechanisms, UC based on triplet-triplet annihilation (TTA-UC) particular has made remarkable progress recent years. The development of new chromophores enabled highly efficient conversion low-intensity into In review, we summarize visible-to-UV TTA-UC, their production films application processes such as catalysis, bond activation polymerization. Finally, challenges opportunities future material applications will be discussed.
Language: Английский
Citations
54
Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(25)
Published: April 18, 2023
Triplet-triplet annihilation upconversion (TTA-UC) with near-infrared (NIR) photosensitizers is highly desirable for a variety of emerging applications. However, the development NIR-to-blue TTA-UC large anti-Stokes shift extremely challenging because energy loss during intersystem crossing (ISC). Here, we develop first NIR-absorbing B,N-heteroarene-based sensitizer (BNS) multi-resonance thermally activated delayed fluorescence (MR-TADF) characters to achieve efficient TTA-UC. The small gap between singlet and triplet excited states (0.14 eV) BNS suppresses ISC loss, its long-delayed lifetime (115 μs) contributes transfer. As result, largest (1.03 among all heavy-atom-free NIR-activatable systems obtained high quantum yield 2.9 % (upper limit 50 %).
Language: Английский
Citations
53
Materials Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 7(19), P. 4304 - 4338
Published: Jan. 1, 2023
This review focuses on fused-ring carbazole derivatives, their molecular design, electronic and photophysical properties, applications as the emitter and/or host material in organic light emitting diodes (OLEDs).
Language: Английский
Citations
52
Journal of Materials Chemistry C, Journal Year: 2023, Volume and Issue: 11(20), P. 6471 - 6511
Published: Jan. 1, 2023
MR-TADF emitters with narrow emission have been developed and are expected to become fourth-generation for HD-OLEDs, molecular design guidelines commercial prospects outlined in this review.
Language: Английский
Citations
47
Nature Photonics, Journal Year: 2024, Volume and Issue: 18(11), P. 1161 - 1169
Published: Aug. 19, 2024
Language: Английский
Citations
39
Chem, Journal Year: 2024, Volume and Issue: 10(5), P. 1485 - 1501
Published: Feb. 15, 2024
Language: Английский
Citations
35