Polycyclization decorated organoboron emitters with hetero[8]helicenes electronic structure for highly‐efficient and stable narrowband circularly polarized electroluminescence

InfoMat, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 27, 2025

Abstract Multiresonance organoboron helicenes are promising narrowband circularly polarized luminescence (CPL) emitters, which, however, still face formidable challenges to balance a large dissymmetry factor ( g lum ) and high efficiency. Here, two pairs of enantiomers P/M ‐BN[8]H‐ICz ‐BN[8]H‐BO) with the same hetero[8]helicene geometric structures developed through polycyclization decoration. We find that it is helicity helicene electronic rather than geometrical one determines molecular property as larger could enhance electron‐orbital coupling structure. Therefore, ‐BN[8]H‐BO who possesses structure realizes nearly one‐order‐of‐magnitude higher (+2.75/−2.52 × 10 −3 photoluminescence quantum yield (PLQY) 99% compared bearing only hetero[6]helicene distribution +2.41/−2.37 −4 PLQY 95%). Moreover, BN[8]H‐BO exhibits green emission peaking at 538 nm full‐width half‐maxima merely 34 nm, narrower most multiresonance CPL helicenes. The corresponding organic light‐emitting diodes simultaneously realize external efficiency 31.7%, an electroluminescence factors EL +5.23/−5.07 , extremely long LT95 (time 95% initial luminance) over 731 h luminance 1000 cd m – 2 . image

Language: Английский

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Hyperfluorescence circularly polarized OLEDs consisting of chiral TADF sensitizers and achiral multi-resonance emitters

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 15, 2025

Developing circularly polarized organic light-emitting diodes (CP-OLEDs) that simultaneously achieve narrow-spectrum emission and high electroluminescence (EL) efficiency remains a formidable challenge. This work prepares two pairs of efficient thermally activated delayed fluorescence (CP-TADF) materials, featuring photoluminescence quantum yields, short lifetimes, good luminescence dissymmetry factors large horizontal dipole ratios. They can function as emitters for sky-blue CP-OLEDs, providing maximum external efficiencies (ηext,maxs) (33.8%) EL (gELs) (−2.64 × 10−3). More importantly, they sensitizers achiral multi-resonance (MR) TADF emitters, furnishing high-performance blue green hyperfluorescence (HF) CP-OLEDs with intense CP-EL ηext,maxs (31.4%). Moreover, tandem HF are fabricated the first time by employing CP-TADF MR-TADF which radiate an extraordinary (51.3%) gELs (4.87 The energy transfer well chirality-induced spin selectivity effect considered to contribute greatly generation from emitters. not only explores materials but also provides facile approach construct realization is challenging. Here, authors report these devices developing chiral

Language: Английский

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Recent development of azahelicenes showing circularly polarized luminescence

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This feature article summarizes the recent developments of azahelicenes showing circularly polarized luminescence.

Language: Английский

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The Role of Chalcogen Substitution and Helical Frameworks in Designing Efficient Chiral Multi‐Resonant TADF Emitters

Advanced Optical Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Abstract Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters that display efficient reverse intersystem crossing (RISC) rates and circularly polarized luminescence (CPL) are of great interest for next‐generation organic light‐emitting diode (OLED) applications, owing to their narrowband emission, high efficiency, remarkable color purity. Here, the photophysical chiroptical properties three series molecules derived from boron/nitrogen‐embedded MR cores by systematically introducing chalcogen atoms (O, S, Se) and/or incorporating ortho‐fused benzo or naphtho groups investigated. Highly correlated quantum‐chemical calculations reveal steric repulsions resulting positions induce molecular distortions twist backbone into helical structures, which enhances chiral properties; incorporation heavier chalcogens increases spin–orbit coupling (SOC), leading enhanced RISC rates. These findings demonstrate several considered exhibit radiative decay (≈10 8 s − ¹), substantial 4 –10 values dissymmetry factor g order 10 −3 , makes them potential candidates CPL applications. Overall, this study highlights complex interplay among substitution, structural modifications, electronic structure in governing MR‐TADF emitters, offers valuable insight rational design CPL‐enabled OLEDs.

Language: Английский

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Synthesis and circularly polarized luminescence properties of sulfur-centered chiral MR-TADF materials

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

Published: March 25, 2025

Language: Английский

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Enantiomerization of helicenes on graphene-like surface: a DFT study

Theoretical Chemistry Accounts, Journal Year: 2025, Volume and Issue: 144(4)

Published: April 1, 2025

Language: Английский

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Realizing Excellent Nonlinear Optical Performance in Near‐Infrared Region of Helicene‐Functionalized Arenes

Advanced Optical Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 11, 2025

Abstract Construction of novel arenes bearing promising optical limiting characteristics in the near‐infrared region is high demand but limited. Herein, two helicene‐embedded 4 and 6 have been strategically synthesized characterized. Under 190 fs pulse width, both them exhibit broadband reverse saturable absorption over a range from 750 to 800 nm, 900 1030 1200 then 1250 nm. The thresholds are determined be 8.1 mJ cm −2 for , 6.2 at 26.4 20.8 respectively. In addition, compounds display obviously widths 22 ps 5 ns wavelength 532 findings clearly suggest that cyclopenta‐ring‐fused pyrene core governs their electronic nature construction such twistacene‐functionalized may design strategy realize relationship between molecular structure nonlinear property.

Language: Английский

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Circularly Polarized Electroluminescence from Organic Emitters

Published: Jan. 1, 2025

Language: Английский

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Efficient Circularly Polarized Electroluminescence Based on Chiral MR‐TADF Materials with Innovative Planar Structure Design Strategy

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 15, 2025

Abstract Chiral multiple resonance thermally activated delayed fluorescence (CP‐MR‐TADF) emitters have obtained attention due to their potential in organic light‐emitting diodes (CP‐OLEDs) with circularly polarized luminescence (CPL). Moreover, the devices always rely on doping concentration aggregation‐caused quenching of CP‐MR‐TADF emitters. Herein, three MR‐TADF materials ( p ‐ICz‐N‐BN , m and ‐prCz‐N‐BN ) are presented by face‐to‐face arrangement indolo[3,2,1‐ jk ]carbazole fluorophore sterically naphthalene bridge, showing emissions peaking at 496–499 nm full‐width half‐maximum values 23–26 photoluminescence quantum yields 91%–98%, respectively. Because asymmetric steric hindrance structures, both separated into innovative planar enantiomers, exhibiting symmetric CPL spectra dissymmetry factors (| g PL |) up 1.1 × 10 −3 2.3 toluene films, Furthermore, OLEDs illustrate maximum external efficiencies 31.5%, 33.7%, 32.4%, respectively, still remain high levels even 20 wt.% almost unchanged emission spectra. Additionally, CP‐OLEDs R / S ‐ display | EL 1.88 1.89

Language: Английский

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Circularly Polarized Luminescence from Decamethylcucurbit[5]uril-triggered Chiral Supramolecular Hydrogels

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

In the presence of macrocyclic host decamethylcucurbit[5]uril, ternary supramolecular hydrogel materials were achieved, which produced white CPL light via FRET and chirality transfer in systems.

Language: Английский

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