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Two 2-substituted 8-hydroxyquinoline ligands ( HL 1 and HL 2 ) containing a cyano group were synthesized and characterized by ESI-MS, NMR spectroscopy and elemental analysis (EA). Solvothermal reactions of the two ligands with ZnX 2 and CdX 2 (X − : NO 3 − and OAc − ) salts afforded three luminescent complexes, i.e., monomeric Zn(II) complex [Zn(L 1 ) 2 ] ( 1 ), trimeric Zn(II) complex [Zn 3 (L 2 ) 6 ] ( 2 ) and tetrameric Cd(II) complex [Cd 4 (L 2 ) 8 ] ( 3 ). These three complexes were characterized by single crystal X-ray diffractions, powder X-ray diffractions (PXRD), thermogravimetry analyses (TGA) and EA, illustrating a lamellar structure facilitated by noncovalent interactions such as aromatic π⋯π stacking and C–H⋯N H-bonds. Further investigations by UV–Vis, photoluminescence (PL) and fluorescence lifetime reveal tunable luminescence from yellow to red among 1 – 3 in the solid state. [ABSTRACT FROM AUTHOR]

Two novel complexes, tetramer [Co 4 L 8 ] ( 1 ) and dimer [Cu 2 L 4 ] ( 2 ) (L = ( E )-2-(2-fluoro-4-methoxystyryl)-8-hydroxyquinoline), were synthesized and characterized by single-crystal X-ray diffractions, powder X-ray diffractions (PXRD), thermal-gravimetric analyses (TGA), infrared radiation (IR) and elemental analyses (EA). In the solid state, both of their supramolecular structures were constructed by C H⋯F dispersive interactions. In addition, the differences in the structure between 1 and 2 have been discussed: supramolecular structures of complex 1 were constructed by C H⋯O and C F⋯π intermolecular interactions, however, supramolecular structures of complex 2 were mainly constructed by C F⋯F C intermolecular interactions and π⋯π stacking. Obviously, the C F group which takes part in attractive interactions with other molecules is important to construct supramolecular structures and plays different roles in the two novel complexes. Magnetic analysis of 1 indicates that the antiferromagnetic coupling dominates the magnetic properties. [ABSTRACT FROM AUTHOR]

A novel 2-substituted-8-hydroxyquinoline ligand ( E )-2-[2-(4-trifluoromethylphenyl)ethenyl]-8-hydroxyquinoline ( 3 , HL ) was synthesized and characterized by ESI-MS, NMR spectroscopy and elemental analysis. Using solvothermal method, a trimeric complex [Zn 3 L 6 ] ( 4 ) was fabricated by self-assembly of Zn(II) ions with 3 . X-ray structural analysis shows that 4 exhibits a trinuclear core, which was bridged and encapsulated by six 8-hydroxyquinolinate-based ligands. The supramolecular structure of 4 features a lamellar solid constructed by aromatic stacking interactions and nonclassical C–H···F hydrogen bonds derived from 4-trifluoromethylphenyl group of the 3 . The coordination behavior of zinc salt and 3 in solution was performed by 1 H NMR, UV–vis and Photoluminescence (PL). The experimental results show that the complex 4 emits yellow luminescence in the solid state. To investigate its properties further, we also studied the thermal stability, photophysical properties (fluorescent emission, lifetime) of complex 4 , and the interactions between 4 and C 60 or EtBr–DNA system. [ABSTRACT FROM AUTHOR]

One novel tetranuclear Cd(II) complex with formula [Cd 4 L 6 (NO 3 ) 2 ] ( 1 ) is accessible by solvothermal reaction of Cd(NO 3 ) 2 with a ( E )-2-[2-(3-thienyl)ethenyl]-8-quinolinol ligand ( HL ), which was characterized by means of 1 H NMR, ESI-MS, elemental analysis, IR and TGA. X-ray structural analysis indicated that 1 exhibited a double open cubane-like core structure, which was bridged by six 8-hydroxyquinolinate-based ligand. Rich aromatic stacking interactions and non-classical C–H···O weak interactions sustain the packing structure. The coordination behavior of cadmium salt and HL in solutions was performed by UV–vis and photoluminescence (PL). The experimental results corroborate that emission spectrum of the title complex in the solid state at room temperature gives strong yellow-green luminescence. In addition, the thermal stability, fluorescent lifetime, electronic calculation and quenching behaviors of C 60 and EtBr-DNA interacted with the compound were also investigated. [ABSTRACT FROM AUTHOR]

A series of 2-arylethenyl-8-hydroxyquinoline ligands ( A1 – A4 ) with a trimethoxyphenyl, naphthyl, 2-fluoro-4-bromophenyl and anthracenyl group and their corresponding Zn(II) complexes ( B1 – B4 ) were synthesized and characterized by means of 1 H NMR, ESI-MS, FT-IR and elemental analysis. A1 and A4 were characterized by single-crystal X-ray crystallography. The aggregation behavior of zinc salt and ligands in solution was investigated by several techniques, containing 1 H NMR, UV–vis and photoluminescence (PL). The electronic nature and volume of arylethenyl substituents affect the absorption wavelength, the emission color, fluorescence lifetime, fluorescence quantum yield and thermostability of Zn(II) complexes. The experiments corroborated that the properties of Zinc(II) complexes can be tuned by introducing different functional substituents. [ABSTRACT FROM AUTHOR]

Thedifferentiation of two nucleophilic amide groups in malonamidesthrough a copper-catalyzed enantioselective intramolecular aryl C–Ncoupling reaction is demonstrated based on an asymmetric desymmetrizationstrategy. Such a method afforded enantioenriched 2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxamidesin high yields and moderate to good enantioselectivity. [ABSTRACT FROM AUTHOR]

The nonlinear optical properties, including two-, three-photon and excited-state absorption phenomena, were observed in three oligomerfluorene derivatives (abbreviated as OF3, OF5 and OF7) by femtosecond (450 fs) laser pulses. Their two-, three-photon and, excited-state absorption properties were studied by open Z-scan and pump-probe measurements. Interestingly, when the numbers of fluorene units increased from 3 to 5, and to 7, the corresponding absorption phenomena changed from three-photon to two-photon induced excited-state phenomena, showed strong structure dependence in these derivatives. The results offer a method to design and synthesize organic molecules for multiphoton materials. It was noted that the three-photon cross-section value ( δ) of OF3 was up to 1.36×10 cm s. Correspondingly, the two-photon ( δ) and excited-state cross-section ( δ) values of OF5 and OF7 also were obtained, and they were 1230 GM and 0.91×10 cm for OF5, and 1780 GM and 1.18×10 cm for OF7, respectively. [ABSTRACT FROM AUTHOR]

Carbonyl small molecule compounds hold great potential as cathode materials for alkali-ion batteries (AIBs) due to their environmental friendliness, structural designability, and high theoretical capacity. However, it's practical application is hindered by intrinsic drawbacks, such as low electrical conductivity and high solubility in organic electrolytes. Additionally, most carbonyl small molecule cathodes can't be charged first in half-cells due to the absence of detachable Li+/Na+/K+ ions, diminishing their appeal when assembled into full cells with alkali-free anodes. This review provides a detailed overview of carbonyl-contained small molecule cathode materials centered around oxygen, including their charge storage mechanisms, solutions to overcome their drawbacks, and the latest research advancements in AIBs. This review also summarizes the electrochemical performance of carbonyl small molecules as cathodes that have been assembled in batteries. Finally, the review outlines the prospects and directions for future research on carbonyl small molecule cathodes. It is hoped that this review will offer meaningful guidance for the development of carbonyl small-molecule cathode materials in AIBs. • The charge storage mechanisms of carbonyl small molecules (CSMs) cathodes were concluded. • The recent progress and corresponding electrochemical performances of CSMs cathode for alkali-ion batteries were summarized. • The current challenges and optimization strategies of CSM cathode were offered. • The perspectives and development direction of CSM cathode were pointed out. [ABSTRACT FROM AUTHOR]

In pursuit of high energy density, lithium metal batteries (LMBs) are undoubtedly the best choice. However, leakage and inevitable dendrite growth in liquid electrolytes seriously hinder its practical application. Solid/quasi‐solid state electrolytes have emerged as an answer to solve the above issues. Especially, polymer electrolytes with excellent interface compatibility, high flexibility, and ease of machining have become a research hotspot for LMBs. Nevertheless, the interface contact between polymer electrolyte and inorganic electrode materials and the low ionic conductivity restrict its development. On account of these, in situ polymerized polymer electrolyte is proposed. Polymer solid electrolytes produced through in situ polymerization promote robust interface contact between the electrolyte and electrode while simplifying the preparation steps. This review summarized the latest research progress in in situ polymerized solid electrolytes for LMBs. These electrolytes were divided into three parts according to their polymerization methods: thermally induced polymerization, chemical initiator polymerization, ionizing radiation polymerization, and so on. Furthermore, we concluded the major challenges and future trends of in situ polymerized solid electrolytes for LMBs. It's hoped that this review will provide meaningful guidance on designing high‐performance polymer solid electrolytes for LMBs. [ABSTRACT FROM AUTHOR]

Nanostructures with curved surfaces and chiral‐directing residues are highly desirable in the synthesis of asymmetric chemicals, but they remain challenging to synthesize without using unique templates due to the disfavored torsion energy of twisted architectures toward chiral centers. Here, a strategy for the facile fabrication of highly cured capsule‐shaped catalysts with chiral interiors by the amplification of molecular chirality via the irreversible cross‐linking of 2D asymmetric laminates is presented. The key to the success of these irregular 2D layers is the use of hierarchical assembly of chiral macrocycles, which can exactly regulate the cured nanostructures as well as asymmetric catalysis. The cross‐linking of 2D laminates from the assembly of hexameric macrocycles with one proline edge gave rise to rarely curled capsules with a diameter of 200–400 nm and excellent enantioselectivities as well as diastereoselectivities for asymmetric aldol reactions (94% ee and 1:13 dr). The tetrameric macrocycles decorated with the chiral block produced further curled porous structures, giving an outstanding enantioselectivities (up to 98% ee and 1:17 dr). The strategy of mechanical surface folding will provide a new insight related to increasing the enantioselectivity of chiral organocatalysts. [ABSTRACT FROM AUTHOR]

Multiple‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters have garnered significant attention in recent years due to their remarkable properties, such as high luminescent quantum yield, robustness, and their compliance with the Broadcast Television 2020 standard for the new generation of ultrahigh‐definition. Despite these advancements, the operational lifetimes of organic light‐emitting diodes (OLEDs) relying on MR‐TADF emitters still fall short for practical application. It is believed that the enhancement of the intrinsic molecular stability of tBu‐DABNA, a fundamental backbone of MR‐TADF emitters, holds great promise to be a universal strategy for all MR‐TADF emitters improving the operational lifetimes of OLEDs. Herein, the design and synthesis of targeted deuteration are reported on donor and/or backbone of MR‐TADF emitters, where the structure‐property relationship between intrinsic molecular stability upon isotopic effect and device operational stability are examined. The isotopic analogs show a gradual increase in the device operational stability and achieve long‐lifetime LT80 (80% of the initial luminance of 1000 cd m−2) of 24.3 h for TADF‐sensitized fluorescence OLED, representing a sevenfold enhancement when compared with the undeuterated counterpart. This strategic deuteration approach underlines the importance of structural modification on materials toward device operational stability. [ABSTRACT FROM AUTHOR]

The π‐conjugated macrocyclic emitters with thermally activated delayed fluorescence (TADF) characteristics have attracted widespread attention in the field of organic electroluminescence (EL) materials due to their unique geometries and excellent luminescence performance. Despite the significant impact of conjugation length and cavity dimensions on molecular conformation, the influence of these factors on the excited‐state properties remains understudied. Herein, we formulated a strategy aimed at modulating the conformation of TADF macrocyclic molecules containing aniline as the donor (D) unit, and triazine as the acceptor (A), linked in D−A and D‐π‐A alternative macrocyclic construction (MC‐TNT and MC‐TST). Corroborated by experimental and theoretical analyses, the compact and conformationally twisted MC‐TNT exhibits efficient blue luminescence in crystalline state, facilitating EL at high doping concentrations with maximum external quantum efficiency (EQEmax) of 13.9 %, leading the field of blue macrocyclic emitters. Notably, MC‐TST with π‐bridge and flat conformation, demonstrates diminished Coulombic repulsion, achieving nearly 100 % photoluminescence quantum yield and superior horizontal dipole orientation of 85 % in 5 wt % doped films, and the corresponding device‘s EQEmax reaches record‐high 32.7 % within the TADF macrocyclic domain. [ABSTRACT FROM AUTHOR]

Organic light‐emitting diodes (OLEDs) using a simple solution‐processing approach have natural advantages in cost‐effective commercialization. However, solution‐processed deep‐red OLEDs are rarely reported due to the scarcity of efficient purely organic narrowband red emitters with commendable film‐forming capabilities. Herein, a simple strategy is proposed to develop organic molecules with narrowband red emission by expanding a rigid conjugated frame to block the rotation of α position in the boron‐dipyrromethene (BODIPY) core due to restricted twisting vibration. Furtherly, by introducing a moderate donor to the meso‐position of the BODIPY core, bathochromic‐shifted emission can be achieved without sacrificing narrow full‐width at half‐maximum (FWHM) by increasing the electron density of the whole molecule and repulsive force of distal units to suppress stretching/scissoring vibration. By employing the developed BODIPY‐derived materials as terminal emitters and thermally activated delayed fluorescence material as assistant host to fabricate solution‐processed OLED devices, a maximum external quantum efficiency of 16.43% is achieved with an emission peak at 672 nm and a FWHM of 28 nm. This work, according to the knowledge, represents the best instance of solution‐processed deep‐red narrowband OLEDs based on typical fluorescent emitters. [ABSTRACT FROM AUTHOR]

Achieving the concurrent manifestation of thermally activated delayed fluorescence (TADF) and aggregation‐induced emission (AIE) within a single molecular system is highly sought after for organic light‐emitting diodes (OLEDs), yet remains rare. In this study, we present a novel TADF‐AIE dye, named PQMO‐PXZ, which has been designed, synthesized, and systematically characterized. Our comprehensive investigation, which includes structural analysis, theoretical calculations, and optical studies, evaluates the potential of PQMO‐PXZ for integration into OLEDs. Unlike existing azaryl‐ketone‐based emitters, PQMO‐PXZ exhibits red‐shifted emission and enhanced luminescence efficiency, due to its rigid structure and strong intramolecular charge transfer characteristics. Significantly, PQMO‐PXZ demonstrates pronounced AIE properties and TADF with a short delayed lifetime. When utilized as the emissive core, OLED devices based on PQMO‐PXZ achieve a respectable external quantum efficiency of up to 11.8 % with minimal efficiency roll‐off, underscoring PQMO‐PXZ's promise as a highly efficient candidate for OLED applications. [ABSTRACT FROM AUTHOR]

Thio-benzothioxanthene imide (BTXI) exhibits long excited state lifetime (τT = 17.7 μs) and high ISC efficiency (ΦΔ = 97%). For the first time, BTXI derivatives were used as photosensitizers for triplet–triplet annihilation upconversion, achieving the highest efficiency of 13.8%. In addition, thio-BTXI derivatives were used as photoinitiators for photopolymerization, resulting in a series of green light-activated radical polymerization systems. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) possesses an ultrahigh theoretical volume capacity (3800 mAh cm−3) and low embedding potential stimulated considerable attention as anodes for sodium‐ion batteries (SIBs). However, its practical application is still hampered by the huge volume variation during the charge/discharge process. To settle this issue, Bi@C nanosheet arrays (Bi@C‐NSA) are fabricated on copper foam via a facile galvanic replacement followed by in situ polymerization of dopamine and an annealing procedure. The carbon‐coated nanosheet array structure not only accommodates the volume expansion during cycling and maintains electrode stability, but also facilitates rapid electron/ion transport. Due to the unique structural design, this Bi@C‐NSA exhibits an impressive capacity of 315.72 mAh g−1 after 1500 cycles under 1 A g−1. Furthermore, a series of in situ/ex situ techniques reveal that this Bi@C‐NSA possesses superior reaction kinetics and undergoes a typical alloying/dealloying storage mechanism. Furthermore, Bi@C‐NSA also achieves commendable reversible capacity and cycling stability in a wide temperature range (0 °C–60 °C). Notably, the assembled Na3V2(PO4)3//Bi@C‐NSA full cell demonstrates a capacity of 325 mAh g−1 after 50 cycles at 0.05 A g−1, which promises for practical applications. This galvanic replacement strategy spearheads a way to prepare nanoarray electrodes and will accelerate the development of sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

A through-space charge transfer pyrene-based fluorophore has been developed for organic light-emitting devices (OLEDs). This material exhibits deep-blue fluorescence, bipolar characteristics, and anti-quenching behavior in the solid state. It proves to be an effective emitter for both doped and nondoped deep-blue OLEDs. [ABSTRACT FROM AUTHOR]

Currently, most photoredox catalysis polymerization systems are limited by high excitation power, long polymerization time, or the requirement of electron donors due to the precise design of efficient photocatalysts still poses a great challenge. Herein, we propose a new approach: the creation of efficient photocatalysts having low ground state oxidation potentials and high excited state energy levels, along with through‐space charge transfer (TSCT) induced intersystem crossing (ISC) properties. A cabazole‐naphthalimide (NI) dyad (NI‐1) characterized by long triplet excited state lifetime (τT=62 μs), satisfactory ISC efficiency (ΦΔ=54.3 %) and powerful reduction capacity [Singlet: E1/2 (PC+1/*PC)=−1.93 eV, Triplet: E1/2 (PC+1/*PC)=−0.84 eV] was obtained. An efficient and rapid polymerization (83 % conversion of 1 mM monomer in 30 s) was observed under the conditions of without electron donor, low excitation power (10 mW cm−2) and low catalyst (NI‐1) loading (<50 μM). In contrast, the conversion rate was lower at 29 % when the reference catalyst (NI‐4) was used for photopolymerization under the same conditions, demonstrating the advantage of the TSCT photocatalyst. Finally, the TSCT material was used as a photocatalyst in practical lithography for the first time, achieving pattern resolutions of up to 10 μm. [ABSTRACT FROM AUTHOR]

Currently, most photoredox catalysis polymerization systems are limited by high excitation power, long polymerization time, or the requirement of electron donors due to the precise design of efficient photocatalysts still poses a great challenge. Herein, we propose a new approach: the creation of efficient photocatalysts having low ground state oxidation potentials and high excited state energy levels, along with through‐space charge transfer (TSCT) induced intersystem crossing (ISC) properties. A cabazole‐naphthalimide (NI) dyad (NI‐1) characterized by long triplet excited state lifetime (τT=62 μs), satisfactory ISC efficiency (ΦΔ=54.3 %) and powerful reduction capacity [Singlet: E1/2 (PC+1/*PC)=−1.93 eV, Triplet: E1/2 (PC+1/*PC)=−0.84 eV] was obtained. An efficient and rapid polymerization (83 % conversion of 1 mM monomer in 30 s) was observed under the conditions of without electron donor, low excitation power (10 mW cm−2) and low catalyst (NI‐1) loading (<50 μM). In contrast, the conversion rate was lower at 29 % when the reference catalyst (NI‐4) was used for photopolymerization under the same conditions, demonstrating the advantage of the TSCT photocatalyst. Finally, the TSCT material was used as a photocatalyst in practical lithography for the first time, achieving pattern resolutions of up to 10 μm. [ABSTRACT FROM AUTHOR]

Current research of triplet–triplet annihilation upconversion (TTA-UC) faces difficulty such as overuse of organic solvents and quenching of excited triplet sensitizers by molecular oxygen. Herein, we propose an efficient and facile preparation strategy of TTA-UC microemulsion to overcome these issues. With simple device and short preparation process, air-stable TTA-UC with a high upconversion efficiency of 16.52% was achieved in microemulsion coassembled from TritonX114, tetrahydrofuran and upconverting chromophores (platinum octaethyl-porphyrin and 9,10-diphenylanthracene). This is comparable to the highest UC efficiency ever reported for TTA-UC microemulsion systems. The excellent UC performance of TX114–THF could be attributed to two perspectives. Firstly, small-size micelle accommodated chromophores up to high concentrations in organic phase, which promoted efficient molecular collision. Additionally, high absorbance at 532 nm ensured full use of excitation light, getting more long wavelength photons involved in the TTA-UC process. Moreover, air-stable TTA-UC also performed well in microemulsion with various surfactants, including nonionic surfactants (Tween 20, Tween 80, Triton X-110, Triton X-114), ionic surfactants (sodium dodecyl sulfate, cetyltrimethyl ammonium bromide) and block copolymers (pluronic F127, pluronic P123), through three conjectural assembly models according to the structural characteristics of surfactant molecules (concentrated, uncompacted and scattered). These discoveries could provide estimable reference for selection of surfactants in relevant fields of TTA-UC. [ABSTRACT FROM AUTHOR]

In recent years, the frequent occurrence of eutrophication problems in water bodies has been caused by changes in the climate environment and overexploitation of natural resources by humans. Chlorophyll-a, as a key indicator for water body assessment, plays an important role in eutrophication research and has a profound impact on the global biogeochemical cycle of the climate process. Studies have shown that temperature can directly or indirectly affect the concentration of chlorophyll-a by influencing the growth of algae and water quality indicators in water bodies. Considering the temperature factor in the inversion of chlorophyll-a concentration is a novel research approach. Based on the influence of temperature on chlorophyll-a concentration, we propose the idea of inverting global ocean chlorophyll-a concentration based on temperature zoning. Using monthly average remote sensing reflectance data from VIIRS (Visible and Infrared Imaging Radiometer Suite), combined with the results of temperature zoning, the OC3V(SST) model was constructed to invert the monthly average chlorophyll-a concentration in the global ocean in October 2018. The OC3V(SST) model has been validated by applying it to the remaining 11 months of January, April, July, and October in 2017, 2018, and 2019, as well as the entire 31-day dataset of October 2018. The results indicate that temperature zonation can significantly improve the inversion accuracy of chlorophyll-a and further explore the spatial distribution patterns of global chlorophyll-a concentrations across various temperature ranges based on monthly averages from the global ocean. Additionally, the study investigates the continuity issues of various models and the correlation between temperature and chlorophyll-a. [ABSTRACT FROM AUTHOR]

Nitroarenes are stable, low‐cost, and readily available starting materials. The directly utilize nitroarenes in synthetically valuable C−N bond formation is of great significance, because the pre‐reduction step to corresponding amines can be avoided. Previously, phosphines and carbon monoxide (CO) are the most widely used reductants in the reductive cyclization or/and carbonylation of nitroarenes. Currently, much attention has been attracted to organosilanes as new potential reducing agents, not only because they are inexpensive, easy‐to‐handle, and mild reagents, but also various novel reaction models of nitroarenes have been explored. In this review, we mainly summarize the recent progress on the reductive coupling of nitroarenes by using organosilanes as the end reductants. We hope that a deep understanding of the reaction model and underlying working mechanism can provide a timely guideline for researchers who are interested in this fantastic area, leading to further exploration of practical and efficient reductive coupling of nitroarenes for C−N bond formation and N‐heterocycle synthesis. [ABSTRACT FROM AUTHOR]

Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) materials hold great promise for advanced high‐resolution organic light‐emitting diode (OLED) displays. However, persistent challenges, such as severe aggregation‐caused quenching (ACQ) and slow spin‐flip, hinder their optimal performance. We propose a synergetic steric‐hindrance and excited‐state modulation strategy for MR‐TADF emitters, which is demonstrated by two blue MR‐TADF emitters, IDAD‐BNCz and TIDAD‐BNCz, bearing sterically demanding 8,8‐diphenyl‐8H‐indolo[3,2,1‐de]acridine (IDAD) and 3,6‐di‐tert‐butyl‐8,8‐diphenyl‐8H‐indolo[3,2,1‐de]acridine (TIDAD), respectively. These rigid and bulky IDAD/TIDAD moieties, with appropriate electron‐donating capabilities, not only effectively mitigate ACQ, ensuring efficient luminescence across a broad range of dopant concentrations, but also induce high‐lying charge‐transfer excited states that facilitate triplet‐to‐singlet spin‐flip without causing undesired emission redshift or spectral broadening. Consequently, implementation of a high doping level of IDAD‐BNCz resulted in highly efficient narrowband electroluminescence, featuring a remarkable full‐width at half‐maximum of 34 nm and record‐setting external quantum efficiencies of 34.3 % and 31.8 % at maximum and 100 cd m−2, respectively. The combined steric and electronic effects arising from the steric‐hindered donor introduction offer a compelling molecular design strategy to overcome critical challenges in MR‐TADF emitters. [ABSTRACT FROM AUTHOR]

Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) materials hold great promise for advanced high‐resolution organic light‐emitting diode (OLED) displays. However, persistent challenges, such as severe aggregation‐caused quenching (ACQ) and slow spin‐flip, hinder their optimal performance. We propose a synergetic steric‐hindrance and excited‐state modulation strategy for MR‐TADF emitters, which is demonstrated by two blue MR‐TADF emitters, IDAD‐BNCz and TIDAD‐BNCz, bearing sterically demanding 8,8‐diphenyl‐8H‐indolo[3,2,1‐de]acridine (IDAD) and 3,6‐di‐tert‐butyl‐8,8‐diphenyl‐8H‐indolo[3,2,1‐de]acridine (TIDAD), respectively. These rigid and bulky IDAD/TIDAD moieties, with appropriate electron‐donating capabilities, not only effectively mitigate ACQ, ensuring efficient luminescence across a broad range of dopant concentrations, but also induce high‐lying charge‐transfer excited states that facilitate triplet‐to‐singlet spin‐flip without causing undesired emission redshift or spectral broadening. Consequently, implementation of a high doping level of IDAD‐BNCz resulted in highly efficient narrowband electroluminescence, featuring a remarkable full‐width at half‐maximum of 34 nm and record‐setting external quantum efficiencies of 34.3 % and 31.8 % at maximum and 100 cd m−2, respectively. The combined steric and electronic effects arising from the steric‐hindered donor introduction offer a compelling molecular design strategy to overcome critical challenges in MR‐TADF emitters. [ABSTRACT FROM AUTHOR]

Organic photosensitizers (PSs) with aggregation‐induced emission (AIE) characteristics have shown several advantages in photodynamic therapy (PDT). However, how to design PSs with the required optical and biological properties is a formidable challenge. In this work, a series of AIE active pyridine‐ and pyridinium‐functionalized carbazole with different substituents are designed and synthesized. Compared to other analogs, BK‐Pys‐BP containing benzophenone moiety on the pyridinium unit produces reactive oxygen species (ROS) efficiently in the presence of light due to its large spin‐orbit coupling constant to promote efficient intersystem crossing. Based on its structure, three molecules with enhanced donor–acceptor strength and conjugation are further investigated to realize emission covering the whole visible region. The cationic nature and excellent ROS generation ability of benzophenone‐containing AIE photosensitizers allows for specific imaging of mitochondria, killing cancer cells, and as a singlet oxygen donor to catalyze the formation of endoperoxides. Thus, the present work presents an effective strategy for creating AIE photosensitizers with efficient ROS generation for wide biological applications. [ABSTRACT FROM AUTHOR]

Review: [17 refs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing the asymmetric end‐group engineering, an asymmetric nonfused‐ring electron acceptor (NFREA) was designed and synthesized. Compared with the symmetric analogs (NoCA‐17 and NoCA‐18), NoCA‐19 possesses broader light absorption range, more coplanar π‐conjugated backbone, and appropriate crystallinity according to the experimental and theoretical results. The organic solar cells based on J52:NoCA‐19 exhibited a power conversion efficiency as high as 12.26%, which is much higher than those of J52:NoCA‐17 (9.50%) and J52:NoCA‐18 (11.77%), mainly due to more efficient exciton dissociation, better and balanced charge mobility, suppressed recombination loss, shorter charge extraction time, longer charge carrier lifetimes, and more favorable blend film morphology. These findings demonstrate the great potential of asymmetric end‐group engineering in exploring low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

We present a red light-activated zincII bis(dipyrrin) symmetry breaking charge transfer (SBCT) architecture, showing a large molar absorption coefficient (ε = 15.4 × 104 M−1 cm−1), high reactive singlet oxygen generation efficiency (ΦΔ ≈ 0.8) and long-lived triplet state (τT = 150 μs) compared to the donor–acceptor analogue dipyrrin-BF2 complex, highlighting the superiority of the SBCT approach. For the first time, we demonstrated the potential of a SBCT scaffold in red-light-induced methyl methacrylate (MMA) polymerization, using a dual photocatalyst excitation approach. [ABSTRACT FROM AUTHOR]

The products are obtained in good yields and with moderate enantiomeric excess. [ABSTRACT FROM AUTHOR]

Dimethyl sulfoxide (DMSO), carrying a highly polarized S = O bond as the H-bond acceptor, possesses an extraordinarily high capacity to compete for H-bond formation. This strongly H-bonding character renders DMSO with a strong ability to interfere with or even disrupt self-assembled structures mediated predominantly by intermolecular H-bonds. While this might be quite disturbing in many applications, in this study, we show that oil gelation actually could benefit significantly from DMSO’s such a strong H-bond-breaking ability. More specifically, we found that use of a minute but optimized amount of DMSO, assisted further by polar acetonitrile of a suitable amount, weakens the H-bonds in the gelling network formed by organogelators to a just right extent so as to allow for a faster disassembly-reassembly of fibers in the wetted powder gelator in oil and subsequent occurrence of rapid room-temperature gelation of both light and heavy crude oils of widely ranging viscosities within 6-25 mins at gelator loadings of ≤12% w/v. [ABSTRACT FROM AUTHOR]

Selective and concise construction of ring systems that are ubiquitous skeletons across chemistry, drugs and materials, is indispensable for human life. Of note, directed C−H annulation with alkynes for the expedient delivery of ring systems holds great importance, featuring step‐ and atom‐economy, mild conditions, and broad substrate scope. However, regioselectivity issues remained when using unsymmetrical alkynes for the directed C−H annulation. Herein, we summarized recent achievements towards solving this problem by developing directing groups, metal catalysts, and alkynes with versatile and traceless functionality that ensure the overall regioselectivity, enantioselectivity, efficiency, and synthetic application. We hope this concept will promote the further development of the precise construction of functional molecules using C−H annulation with unsymmetrical alkynes. [ABSTRACT FROM AUTHOR]

The design of efficient heavy atom‐free triplet photosensitizers (PSs) based on through bond charge transfer (TBCT) features is a formidable challenge due to the criteria of orthogonal donor‐acceptor geometry. Herein, we propose using parallel (face‐to‐face) conformation carbazole‐bodipy donor‐acceptor dyads (BCZ‐1 and BCZ‐2) featuring through space intramolecular charge transfer (TSCT) process as efficient triplet PS. Efficient intersystem crossing (ΦΔ=61 %) and long‐lived triplet excited state (τT=186 μs) were observed in the TSCT dyad BCZ‐1 compared to BCZ‐3 (ΦΔ=0.4 %), the dyad involving TBCT, demonstrating the superiority of the TSCT approach over conventional donor‐acceptor system. Moreover, the transient absorption study revealed that TSCT dyads have a faster charge separation and slower intersystem crossing process induced by charge recombination compared to TBCT dyad. A long‐lived charge‐separated state (CSS) was observed in the BCZ‐1 (τCSS=24 ns). For the first time, the TSCT dyad was explored for the triplet‐triplet annihilation upconversion, and a high upconversion quantum yield of 11 % was observed. Our results demonstrate a new avenue for designing efficient PSs and open up exciting opportunities for future research in this field. [ABSTRACT FROM AUTHOR]

The design of efficient heavy atom‐free triplet photosensitizers (PSs) based on through bond charge transfer (TBCT) features is a formidable challenge due to the criteria of orthogonal donor‐acceptor geometry. Herein, we propose using parallel (face‐to‐face) conformation carbazole‐bodipy donor‐acceptor dyads (BCZ‐1 and BCZ‐2) featuring through space intramolecular charge transfer (TSCT) process as efficient triplet PS. Efficient intersystem crossing (ΦΔ=61 %) and long‐lived triplet excited state (τT=186 μs) were observed in the TSCT dyad BCZ‐1 compared to BCZ‐3 (ΦΔ=0.4 %), the dyad involving TBCT, demonstrating the superiority of the TSCT approach over conventional donor‐acceptor system. Moreover, the transient absorption study revealed that TSCT dyads have a faster charge separation and slower intersystem crossing process induced by charge recombination compared to TBCT dyad. A long‐lived charge‐separated state (CSS) was observed in the BCZ‐1 (τCSS=24 ns). For the first time, the TSCT dyad was explored for the triplet‐triplet annihilation upconversion, and a high upconversion quantum yield of 11 % was observed. Our results demonstrate a new avenue for designing efficient PSs and open up exciting opportunities for future research in this field. [ABSTRACT FROM AUTHOR]

The development of persistent room‐temperature phosphorescence (pRTP) materials has been rapid in recent years; however, producing pRTP materials with high luminescent characteristics, mechanical strength, and processability is a difficult issue. Herein, a new class of pRTP materials named carbonized oligomer‐like dots (CODs) is reported, which have injection molding capacity and high mechanical strength in castings. The luminescence and mechanical properties of the CODs (PN1‐PN4) may be altered by altering the quantity of phosphoric acid and diethylenetriamine using a microwave‐assisted heating technique. Among them, the longest lifetime of PN3 attains 1.21 s with an afterglow time of over 20 s, while the maximum Young's modulus of PN1 is up to 2.36 GPa. The existence of n–π* transition is beneficial to promote the intersystem crossing, and multiple hydrogen bonds in the aggregates play a crucial role in the formation of pRTP with mechanical and hot melt adhesive properties. This study may pave the way for the development of pRTP materials with superior mechanical strength in the fields of information encryption and flexible displays. [ABSTRACT FROM AUTHOR]

Organic persistent luminescence (pL) systems with photoresponsive dynamic features have valuable applications in the fields of data encryption, anticounterfeiting, and bioimaging. Photoinduced radical luminescent materials have a unique luminous mechanism with the potential to achieve dynamic pL. It is extremely challenging to obtain radical pL under ambient conditions; on account of it, it is unstable in air. Herein, a new semialiphatic polyimide‐based polymer (A0) is developed, which can achieve dynamic pL through reversible conversion of radical under photoexcitation. A "joint–donor–spacer–acceptor" molecular design strategy is applied to effectively modulate the intramolecular charge‐transfer and charge‐transfer complex interactions, resulting in effective protection of the radical generated under photoirradiation. Meanwhile, polyimide‐based polymers of A1–A4 are obtained by doping different amine‐containing fluorescent dyes to modulate the dynamic afterglow color from green to red via the triplet to singlet Förster resonance energy‐transfer pathway. Notably, benefiting from the structural characteristics of the polyimide‐based polymer, A0–A4 have excellent processability, thermal stability, and mechanical properties and can be applied directly in extreme environments such as high temperatures and humidity. [ABSTRACT FROM AUTHOR]

High‐contrast mechano‐responsive luminescence (MRL) materials with mechano‐induced emission enhancement properties are fascinating candidates but few, for applications in rewritable media and recording devices. Here, an interesting design strategy of "Y‐shape" donor‐acceptor (D−A) type molecules for high‐contrast MRL materials was presented, based on substituted diphenylamine donor and planar acceptor. Interestingly, their D−A torsion angles are small in crystals but increased after ground, resulted in planar and twist intramolecular charge transfer (PICT and TICT) states, respectively. Therefore, high‐contrast MRL switching between weak blue (450 nm) fluorescence and bright yellow (552 nm) thermally activated delayed fluorescence (TADF) can be achieved for compound TXDO (4,4′‐dimethoxydiphenylamine donor), which photoluminescence quantum yield increased from 2.8 % to 54.7 % after ground. Most importantly, the two independent D−A conjugation dihedral angles are actually independent in the "Y‐shape" molecules. Especially for compound TXDT (4,4′‐di‐tert‐butyldiphenylamine donor), its crystal exhibited both PICT and TICT processes inside, resulted from the different dihedral angles of 11.8° and 35.5°, respectively. The TXDT crystal thus showed dual‐peak emission, including both TICT fluorescence and PICT room‐temperature phosphorescence. Therefore, this strategy of "Y‐shape" D−A type molecules provide a new approach to design advanced luminescent materials with mechano‐induced TADF feature, for high‐contrast MRL and single‐component white luminescence. [ABSTRACT FROM AUTHOR]

Regiodivergent [3+2] and [4+2] C−H annulation of imines and imidate esters with unsymmetrical alkynes has been achieved under Rh(III) catalysis. Further transformation of the aldehyde and TMS functionality on the indene products is also demonstrated. The current work highlights the alcohols‐directed multiple C−H annulation of imines and imidate esters, leading to diverse fused heterocycles. [ABSTRACT FROM AUTHOR]

The development of P(O)–heteroatom bond-forming reactions is of vital importance. However, previous methods all have their own limitations and drawbacks. Herein, we disclose an efficient, green, and direct photocatalytic phosphorylation of heteroatom nucleophiles under the irradiation of 12 W blue LEDs at room temperature using acid red 51 as the photocatalyst and eco-friendly air as the sole oxidant. The newly developed reaction shows broad substrate scope under halide-, base-, metal-, and additive-free conditions, providing practical and scalable access to phosphinic fluorides, phosphinic amides, phosphoramidates, and phosphinates. Mechanistic studies on the phosphorylation reaction suggest that a phosphorus-centered radical cation generated from the P(O)–H reagent via a photocatalytic single electron transfer (SET) might be the main reactive species involved in this transformation. [ABSTRACT FROM AUTHOR]

LiNi 0.6 Co 0.2 Mn 0.2 O 2 //graphite full cell, due to its high energy density as the most promising candidate for power batteries received increased attention, but the severe capacity loss under high-temperature conditions prevents their large-scale application. Here, glutaric anhydride (GA) and succinic anhydride (SA) as electrolyte additives are investigated to overcome the high-temperature problem of LiNi 0.6 Co 0.2 Mn 0.2 O 2 //graphite cells. Due to the unique film-forming features and high-temperature stability, the cells containing 0.5% GA and 0.5% SA can retain capacity retention of 91.2% and 92.4% stored at 60 ​°C for 15 days, corresponding to a negligible capacity loss of 4.6 and 0.8 mAh g-1 after 200 cycles, respectively. In addition, the lifespans of cells under 25 ​°C are also significantly extended by introducing GA and SA into the electrolytes. Electrochemical and spectroscopic techniques results indicate the full cell capacity loss is predominantly caused by the unstable anode solid electrolyte interphase (SEI) layer and a stable SEI film derived from GA and SA is formed on the graphite electrode surfaces. The SEI film can effectively inhibit the consumption of electrolytes and enhance the high-temperature performance of cells. This work paves a way for moderating high energy density cells' work under high-temperature operation by developing special anodic film-forming electrolyte additives. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO)‐based polymer electrolytes with good flexibility and viscoelasticity, low interfacial resistance, and fabricating cost have caught worldwide attention, but their practical application is still hampered by the instability at high voltages and the low ionic conductivity (10−8 to 10−6 S cm−1). Herein, we rationally designed defects‐abundant Ga2O3 nanobricks as multifunctional fillers and constructed a PEO‐based organic‐inorganic electrolyte for lithium metal batteries. Due to the abundant O‐defects feature of Ga2O3 filler, this PEO‐based composite electrolyte not only broadens electrochemical stability window (over 5.3 V versus Li/Li+) but also in situ forms a Li–Ga alloy and solid electrolyte interphase (SEI) film during the cycling process causing a rapid diffusion of Li+ ions. The as‐prepared electrolyte has good interface compatibility with Li metal (without short‐circuiting over 500 h at 0.2 mA cm−2) and possesses superior high ionic conductivity. The assembled all‐solid‐state LiFePO4//Li cells attained an excellent cycling performance of 146 mAh g−1 over 100 cycles at 0.5 C. The XPS analysis reveals that Ga2O3 nanobricks can form in situ a Li−Ga alloy layer at the polymer/anode interface. This work shed a light on designing high ionic conductivity lithium alloys in the composite electrolyte, which can improve the electrochemical properties of PEO‐based polymer electrolytes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Deep-blue materials are constructed through the modification of anthracene with non-conjugated weak electron-withdrawing and electron-donating groups. • The doped OLEDs achieved a maximum EQE of over 10%, with CIE coordinates approaching the BT.2020 blue standard. • The introduction of weak electron-withdrawing PO group gave rise to multiple hRISC channels. The development efficient deep-blue fluorescent materials present a significant challenge in the field of organic optoelectronics. The hot exciton mechanism, which facilitates the transition of excitons from high-energy excited triplet states (T n , n ≥ 2) to singlet states (S m , m ≥ 1) via reverse intersystem crossing (hRISC) pathways, has emerged as an effective strategy for designing efficient organic light-emitting diodes (OLEDs). In this study, we modified anthracene with non-conjugated triphenylphosphine oxide (PO) and tetraphenylsilane (TPS) groups to construct two positional isomers, p-TPSAnPO and m-TPSAnPO. Photophysical studies indicate that the weak electron-withdrawing and electron-donating of the PO and TPS groups endow p-TPSAnPO and m-TPSAnPO with local excited (LE) characteristics in their lowest singlet state (S 1), resulting in highly efficient deep-blue emission. Doped devices based on p-TPSAnPO and m-TPSAnPO achieved maximum external quantum efficiencies (EQE max) of 10.07 % and 10.77 %, respectively, with Commission Internationale de l ́Eclairage (CIE) coordinates of (0.155, 0.043) and (0.152, 0.048), approaching BT.2020 blue standard. The theoretical calculations further reveal that the S 1 , T 2 , and T 3 states of these materials are localized on the anthracene moiety, while the higher-energy S 2 and T 4 states are induced by the electron-withdrawing PO group, forming charge transfer (CT) and hybridized local and charge transfer (HLCT) states. The transitions between these high-energy states create multiple hRISC pathways. Additionally, sensitization experiments on high-energy triplet states confirm that these materials indeed exhibit effective hRISC processes, enabling them to achieve high efficiency in electroluminescent applications. This work provides important theoretical and experimental guidance for designing efficient anthracene-based hot exciton deep-blue materials. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) dyes are promising for applications like bioimaging, sensing, and optoelectronic devices due to their efficient exciton utilization without noble metals, making them ideal for organic light-emitting diodes (OLEDs). In this contribution, we introduce a new TADF emitter, 3-(9,9-dimethylacridin-10(9 H)-yl)-12 H -chromeno[2,3- b ]quinolin-12-one (CQLO-DMAC), which incorporates an intramolecular oxygen-locked azaryl ketone acceptor, CQLO. This design enhances molecular rigidity and electron-accepting strength. The CQLO-DMAC compound, featuring a bulky donor, shows significant intramolecular charge transfer and TADF emission. Comprehensive analyses, including spectroscopic studies and theoretical calculations, reveal high luminescence efficiency and reduced non-radiative losses. Utilizing CQLO-DMAC in OLEDs, we achieved a green-yellow emission peak at 548 nm and a maximum external quantum efficiency of 17.4 %. The findings highlight the potential of CQLQ as a highly effective acceptor in designing of TADF electroluminescent dyes. [Display omitted] • An oxygen-locked azaryl ketone acceptor CQLO is designed for constructing TADF emitter (CQLO-DMAC). • CQLO-DMAC exhibits notable TADF properties, facilitating efficient triplet-to-singlet spin conversion. • CQLO-DMAC demonstrates bright TADF emission with a decent PLQY of 72 %. • High electroluminescence efficiency with an EQE of up to 17.4 % are demonstrated. [ABSTRACT FROM AUTHOR]

Despite vast applications of macrocycles in supramolecular chemistry, achieving long‐lived emissions including room‐temperature phosphorescence (RTP) or thermally activated delayed fluorescence (TADF) for potential use still presents a great challenge. This work first reports hydrogen‐bonded (H‐bonded) macrocycles emitting RTP and TADF by introducing various donors onto the same aramide skeleton containing a rigid acceptor. The formation of charge transfer effectively enhances the photoluminescence efficiency. Aromatic carbonyl groups promote the intersystem crossing. The drastically reduced flexibility of chromophores fixed by the H‐bonded macrocyclic framework contributes to suppress the nonradiative decay to stabilize triplet excitons. Therefore, RTP and TADF are acquired by altering donors, and are systematically revealed by comparisons with control compounds and theoretical calculations. Finally, near white‐light emission (CIE, 0.30, 0.33) is realized via host–guest interactions. [ABSTRACT FROM AUTHOR]

Multiple-resonance (MR) thermal activated delayed fluorescence (TADF) emitters have attracted increasing attention in organic electroluminescence devices, owing to their superior quantum efficiency and narrowband emission for high color purity. However, MR-TADF materials often suffer from severe aggregation-caused quenching (ACQ) and efficiency roll-off problems due to their rigid planar structures and the lack of sufficient charge-transfer (CT) characters with inefficient reverse intersystem crossing (RISC). Herein, by attaching electron-rich triphenylamine (TPA) with twisted spatial conformation to the MR framework, two efficient narrowband MR-TADF emitters, namely BNCz-pTPA and BNCz-mTPA, are developed. The TPA substituent endows the new emitters with aggregation-induced emission enhancement (AIEE) for ACQ suppression. The unprecedented AIEE-MR-TADF emitters exhibit CT character in high-lying triplet excited states for faster RISC, while the locally-excited (LE) character of the first singlet excited state is retained for narrowband emission with high emission efficiency. An organic light-emitting diode (OLED) based on BNCz-pTPA exhibits a maximum external quantum efficiency of 27.3% with slow efficiency roll-off, demonstrating much higher performances than those of the BNCz-based OLED. This study may provide a simple but effective approach to constructing high-performance emitters for wide-color-gamut OLED displays. [ABSTRACT FROM AUTHOR]

The development of photoinduced luminescent radicals with dynamic emission color is still challenging. Herein we report a novel molecular radical system (TBIQ) that shows photo‐controllable luminescence, leading to a wide range of ratiometric color changes via light excitation. The conjugated skeleton of TBIQ is decorated with steric‐demanding tertiary butyl groups that enable appropriate intermolecular interaction to make dynamic intermolecular coupling possible for controllable behaviors. We reveal that the helicenic pseudo‐planar conformation of TBIQ experiences a planarization process after light excitation, leading to more compactly stacked supermolecules and thus generating radicals via intermolecular charge transfer. The photo‐controllable luminescent radical system is employed for a high‐level information encryption application. This study may offer unique insight into molecular dynamic motion for optical manufacturing and broaden the scope of smart‐responsive materials for advanced applications. [ABSTRACT FROM AUTHOR]

The development of photoinduced luminescent radicals with dynamic emission color is still challenging. Herein we report a novel molecular radical system (TBIQ) that shows photo‐controllable luminescence, leading to a wide range of ratiometric color changes via light excitation. The conjugated skeleton of TBIQ is decorated with steric‐demanding tertiary butyl groups that enable appropriate intermolecular interaction to make dynamic intermolecular coupling possible for controllable behaviors. We reveal that the helicenic pseudo‐planar conformation of TBIQ experiences a planarization process after light excitation, leading to more compactly stacked supermolecules and thus generating radicals via intermolecular charge transfer. The photo‐controllable luminescent radical system is employed for a high‐level information encryption application. This study may offer unique insight into molecular dynamic motion for optical manufacturing and broaden the scope of smart‐responsive materials for advanced applications. [ABSTRACT FROM AUTHOR]

Tuning the redox potential of commonly available photocatalyst to improve the catalytic performance or expand its scope for challenging synthetic conversions is an ongoing demand in synthetic chemistry. Herein, the excited state properties and redox potential of commercially available [Ru(bpy)3]2+ photocatalyst were tuned by modifying the structure of the bipyridine ligands with electron‐donating/withdrawing units. The visible‐light‐mediated photoredox phosphorylation of tertiary aliphatic amines was demonstrated under mild conditions. A series of cross‐dehydrogenative coupling reactions were performed employing the RuII complexes as photocatalyst giving the corresponding α‐aminophosphinoxides and α‐aminophosphonates via carbon‐phosphorus (C−P) bond formation. [ABSTRACT FROM AUTHOR]

The exploration of green C–H oxidation for the rapid construction of functional molecules, remains a permanent goal in synthetic chemistry. Herein, a traceless N-nitroso enabled oxidative Heck and amidation cascade was realized, leading to quinolinones that feature green oxidation and great functional group tolerance. The expedient construction of quinolinone containing pharmaceuticals including Flucarbril, Clostamide and Aripiprazole was achieved in a concise and environmentally friendly manner. [ABSTRACT FROM AUTHOR]

Narrowband emitting fluorophores exhibit immense potentials for organic light‐emitting diodes (OLEDs) with high color purity. However, it's still hard to simultaneously realize short‐wavelength ultraviolet (UV) or near ultraviolet emission (NUV) while maintaining a narrowed full width at half maximum (FWHM) value, and rare work focus on such challenging pursuit. Herein, an ingenious synthetic method was devised to achieve emitters with coplanar structure. 11‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)indolo[3,2,1‐jk]carbazole (ICZ‐TAZ) was designed to realize narrowed UV emission both in photoluminescence (PL) and electroluminescence (EL) which benefited from the suppression of vibronic coupling. UV/NUV OLEDs based on ICZ‐TAZ achieve external quantum efficiency (EQE) maximums of 3.26 % peaks @ 388 nm and 4.02 % peaks @ 406 nm with small FWHM of 32 nm and 46 nm, respectively, corresponding with reduced efficiency roll‐off at luminance of 100 cd m−2. [ABSTRACT FROM AUTHOR]

Narrowband emitting fluorophores exhibit immense potentials for organic light‐emitting diodes (OLEDs) with high color purity. However, it's still hard to simultaneously realize short‐wavelength ultraviolet (UV) or near ultraviolet emission (NUV) while maintaining a narrowed full width at half maximum (FWHM) value, and rare work focus on such challenging pursuit. Herein, an ingenious synthetic method was devised to achieve emitters with coplanar structure. 11‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)indolo[3,2,1‐jk]carbazole (ICZ‐TAZ) was designed to realize narrowed UV emission both in photoluminescence (PL) and electroluminescence (EL) which benefited from the suppression of vibronic coupling. UV/NUV OLEDs based on ICZ‐TAZ achieve external quantum efficiency (EQE) maximums of 3.26 % peaks @ 388 nm and 4.02 % peaks @ 406 nm with small FWHM of 32 nm and 46 nm, respectively, corresponding with reduced efficiency roll‐off at luminance of 100 cd m−2. [ABSTRACT FROM AUTHOR]