Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 158958 - 158958
Published: Dec. 1, 2024
Language: Английский
Beilstein Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 21, P. 935 - 944
Published: May 14, 2025
Since the discovery of donor–acceptor (D–A) type molecules in field materials science, they have found great applicability photocatalysis. Most these compounds are based on complex D–A–D structures or multi-D–A systems, such as 4CzIPN. Whereas systems been widely studied and applied photocatalysts, simpler D–A remain less explored. Nevertheless, simplicity makes them ideal to further understand structure–property relationship for optimizing their photocatalytic performance by modification different subunits. In particular, featuring sulfur-based acceptors nitrogen donors gained increasing attention use photoredox catalysts. This study introduces a new family exploring various donors, including novel tribenzo[ b,d,f ]azepine (TBA) unit 5 H -dibenz[ b,f (IMD). Our findings demonstrate that simple exhibit promising properties, comparable those more systems.
Language: Английский
Citations
0
Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown
Published: July 19, 2024
Abstract Heteroatom‐embedded helical nanographenes (NGs) constitute an important and appealing class of intrinsically chiral materials. In this work, a series B,N‐embedded NGs (BN‐HNGs) bearing azepines was synthesized via stepwise regioselective cyclodehydrogenation. First, the phenyl‐ or nitrogen‐bridged dimers were efficiently clipped into highly congested model compounds 1 2 . Later, controllable Scholl reactions tetraphenyl‐tethered precursor generated 1, 7 8 new C−C bonds, thereby establishing robust method for preparation nonalternant BN‐HNGs with up to 31 fused rings. The bilayer nature unambiguously verified by X‐ray diffraction analysis. chirality transferred stereogenic boron centers upon fluoride coordination, concave‐concave structure comply skeleton. Notably, largest BN‐HNG ( 6 ) spontaneously resolved homochiral 4 helix as molecular spiral staircase during crystallization conglomerate formation at single‐crystal scale. large twisted C ‐symmetric π‐surface dynamic skeleton induced curved might have synergistic effects on self‐recognition enantiomers achieve intriguing spontaneous resolution behavior. chiroptical properties enantiomer further investigated, revealing that had strong response in visible range (400–700 nm).
Language: Английский
Citations
3
Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown
Published: Dec. 17, 2024
Abstract Due to higher exciton energy, the deep‐blue organic light‐emitting diodes (OLEDs) are most challenging among trichromatic emitters. In this work, three novel blue emitters with multi‐resonance (MR) effects reported based on N , ,5,9‐tetraphenyl‐5,9‐dihydro‐5,9‐diaza‐13b‐boranaphtho[3,2,1‐ de ]anthracen‐7‐amine (PAB) skeleton, incorporating fluorine and methyl groups. Compound 2FPAB MePAB exhibit ultra‐pure emission peaks at 436 448 nm respectively. The device achieves a maximum external quantum efficiency of 19.8% an ultralow CIEy value 0.046 full‐width‐at‐half‐maximum (FWHM) 29 in bottom emitting device. Additionally, peripheral cladding atoms extends conjugation framework slightly enhances electron acceptance character boron atom ortho‐position. This leads redshift spectrum enhanced photoluminescence yield (PLQY) up 93% for MePABF. Furthermore, potential application as sensitizer MePABF is examined by fabricating TADF‐sensitized‐TADF (TST) results show significantly reduced roll‐off improved performance, (EQE max ) 25.1% FWHM nm.
Language: Английский
Citations
3
Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown
Published: Sept. 9, 2024
Abstract Multiple resonance thermally activated delayed fluorescence (MR‐TADF) emitters are promising for high‐definition organic light‐emitting diodes (OLEDs) due to their high exciton utilization and color purity. However, strong interchromophore interactions cause most MR‐TADF with planar structures aggregate at doping concentrations, leading degraded efficiencies. Herein, using benzenesulfonyl‐functionalized dibenzothiophene sulfoximine steric effects, three (2SBN, 3SBN, 4SBN) synthesized by coupling the classic DtBuCzB skeleton different sites. Three exhibit green or blue‐green emission full width half maximum (FWHM) values less than 29 nm photoluminescence quantum yields exceeding 90%. OLEDs based on 2SBN, 4SBN achieve external efficiency (EQE max ) of 30.1%, 27%, 33.8%, respectively, a 5 wt.% concentration. Notably, distorted conformation suppressed intermolecular interaction, OLED remains EQE 28.9% concentration 20 wt.%. These results demonstrate feasibility molecular design modulate spatial conformations via positional isomerism develop reduced quenching.
Language: Английский
Citations
2
Chemical Science, Journal Year: 2024, Volume and Issue: unknown
Published: Jan. 1, 2024
Spiro-acridine modified N/B/O type MR-TADF emitters realized deep blue fluorescence with an EQE max of 20.5% and CIE (0.147, 0.048), which is state-of-the-art efficiency for deep-blue MR y approaching the BT.2020 standard.
Language: Английский
Citations
2
Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(42)
Published: July 19, 2024
Abstract Heteroatom‐embedded helical nanographenes (NGs) constitute an important and appealing class of intrinsically chiral materials. In this work, a series B,N‐embedded NGs (BN‐HNGs) bearing azepines was synthesized via stepwise regioselective cyclodehydrogenation. First, the phenyl‐ or nitrogen‐bridged dimers were efficiently clipped into highly congested model compounds 1 2 . Later, controllable Scholl reactions tetraphenyl‐tethered precursor generated 1, 7 8 new C−C bonds, thereby establishing robust method for preparation nonalternant BN‐HNGs with up to 31 fused rings. The bilayer nature unambiguously verified by X‐ray diffraction analysis. chirality transferred stereogenic boron centers upon fluoride coordination, concave‐concave structure comply skeleton. Notably, largest BN‐HNG ( 6 ) spontaneously resolved homochiral 4 helix as molecular spiral staircase during crystallization conglomerate formation at single‐crystal scale. large twisted C ‐symmetric π‐surface dynamic skeleton induced curved might have synergistic effects on self‐recognition enantiomers achieve intriguing spontaneous resolution behavior. chiroptical properties enantiomer further investigated, revealing that had strong response in visible range (400–700 nm).
Language: Английский
Citations
1
Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown
Published: Oct. 14, 2024
Abstract Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) molecules have experienced great success in organic light‐emitting diodes (OLEDs) owing to their outstanding quantum efficiencies and narrow full width at half‐maximums (FWHMs). However, the reverse intersystem crossing (RISC) rates of MR‐TADF emitters are usually small, which will lead relatively long triplet exciton lifetime severe efficiency roll‐off. Here, we report an effective molecular design strategy introduce multichannel RISC pathways thus increase without compromising color fidelity emission by “hybridized long‐short axis (HLSA)” strategy. The TPA‐CN‐BN shows a near‐unity photoluminescence yield, rapid rate 1.4×10 5 s −1 , FWHM 23 nm, small singlet‐triplet energy gap (Δ E ST ) 0.06 eV solution. non‐sensitized OLED based on exhibits narrowband with 31 company external (EQE) 37.9 %. Notably, device low roll‐off as EQEs maintain 34.8 % 21.8 100 1000 cd m −2 respectively, representing best performance for single‐host OLEDs BCzBN skeleton. This study provides fresh promising approach realize high‐performance high purity remarkable efficiency.
Language: Английский
Citations
1
Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown
Published: Oct. 14, 2024
Multi-resonance thermally activated delayed fluorescence (MR-TADF) molecules have experienced great success in organic light-emitting diodes (OLEDs) owing to their outstanding quantum efficiencies and narrow full width at half-maximums (FWHMs). However, the reverse intersystem crossing (RISC) rates of MR-TADF emitters are usually small, which will lead relatively long triplet exciton lifetime severe efficiency roll-off. Here, we report an effective molecular design strategy introduce multichannel RISC pathways thus increase without compromising color fidelity emission by "hybridized long-short axis (HLSA)" strategy. The TPA-CN-BN shows a near-unity photoluminescence yield, rapid rate 1.4×10
Language: Английский
Citations
1
Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown
Published: Dec. 26, 2024
Abstract Achieving high‐efficiency and narrowband deep‐blue emission is of great significance for organic light‐emitting diodes (OLEDs). Herein, a novel selenium‐containing spiro‐acridine donor, DspiroSe, designed constructing highly efficient blue emitters. The spiro structure DspiroSe contributes to suppressed aggregation‐caused quenching, while the selenium atom provides heavy‐atom effect. By attaching multiple resonance skeleton with different linkage strategies, two isomeric emitters sSeDDBN PsSe‐DABNA are obtained, which show promise as candidates OLEDs. Note that methods enable tuning spectrum from sky‐blue deep‐blue, demonstrating exceptional characterized by full‐width at half‐maximum 18 nm peak wavelength 445 in solution. Both exhibit high photoluminescence quantum yields exceeding 90% films, OLEDs using them achieve maximum external efficiencies (EQE max ) 26.5% 14.6%, respectively. utilizing TADF assistant host, EQE further increases 28.5% 19.1% PsSe‐DABNA. Notably, based excellent color purity Commission Internationale de l'Eclairage coordinates (0.145, 0.052), closely approaching BT.2020 standard.
Language: Английский
Citations
1
Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 155350 - 155350
Published: Sept. 1, 2024
Language: Английский
Citations
0