Frontiers in circularly polarized luminescence: molecular design, self-assembly, nanomaterials, and applications

Science China Chemistry, Journal Year: 2021, Volume and Issue: 64(12), P. 2060 - 2104

Published: Nov. 10, 2021

Language: Английский

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High Performance of Simple Organic Phosphorescence Host–Guest Materials and their Application in Time‐Resolved Bioimaging

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(18)

Published: March 27, 2021

Abstract The study of purely organic room‐temperature phosphorescence (RTP) has drawn increasing attention because its considerable theoretical research and practical application value. Currently, RTP materials with both high efficiency (Φ P > 20%) a long lifetime (τ 10 s) in air are still scarce due to the lack related design guidance. Here, new strategy increase performance by integrating host guest one doping system form triplet exciplex, is reported. With these materials, high‐contrast labeling tumors living mice encrypted patterns thermal printing successfully realized taking advantage afterglow time (up 25 min aqueous media) (43%).

Language: Английский

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Nonconventional luminophores: characteristics, advancements and perspectives

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(22), P. 12616 - 12655

Published: Jan. 1, 2021

Mechanisms, recent advancements and perspectives concerning nonconventional luminophores free of classic conjugates but with intrinsic photoluminescence are discussed.

Language: Английский

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Molecular mechanism of aggregation‐induced emission

Aggregate, Journal Year: 2021, Volume and Issue: 2(5)

Published: June 3, 2021

Abstract Deep understanding of the inherent luminescence mechanism is essential for development aggregation‐induced emission (AIE) materials and applications. We first note that intermolecular excitonic coupling much weaker in strength than intramolecular electron‐vibration a majority newly termed AIEgens, which leads to peak position insensitive coupling, hence conventional model J‐aggregation cannot effectively explain their AIE phenomena. Then, using multiscale computational approach coupled with our self‐developed thermal vibration correlation function rate formalism transition‐state theory, we quantitatively investigate aggregation effect on both radiative nonradiative decays molecular excited states. For decay processes, propose lowest state could convert from transition dipole‐forbidden “dark” dipole‐allowed “bright” upon aggregation. radiationless demonstrate blockage via relaxation (BNR‐VR) harmonic region or removal isomerization (RNR‐ISO) minimum energy crossing point (RNR‐MECP) beyond variety aggregates. Our theoretical work not only justifies plethora experimental results but also makes reliable predictions design can be experimentally verified. Looking forward, believe this review will benefit deep about universality phenomenon further extending scope systems novel

Language: Английский

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Assembly and Applications of Macrocyclic-Confinement-Derived Supramolecular Organic Luminescent Emissions from Cucurbiturils

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(9), P. 9032 - 9077

Published: March 21, 2022

Cucurbit[n]urils (Q[n]s or CB[n]s), as a classical of artificial organic macrocyclic hosts, were found to have excellent advantages in the fabricating tunable and smart luminescent materials aqueous media solid state with high emitting efficiency under rigid pumpkin-shaped structure-derived macrocyclic-confinement effect recent years. This review aims give systematically up-to-date overview Q[n]-based supramolecular emissions from confined spaces triggered host–guest complexes, including assembly fashions mechanisms macrocycle-based well their applications. Finally, challenges outlook are provided. Since this class emissions, which essentially derived cavity-dependent confinement resulting fashions, emerged only few years ago, we hope will provide valuable information for further development light-emitting other related research fields.

Language: Английский

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Organic molecular aggregates: From aggregation structure to emission property

Aggregate, Journal Year: 2021, Volume and Issue: 2(4)

Published: June 24, 2021

Abstract Organic molecular aggregates have attracted widespread attention over the past decade owing to their unique optoelectronic properties in aggregate state, which mainly involves effects of aggregation structure as well packing mode. Although many examples H‐ and J‐aggregates defined by exciton model been found, there are also other types unconventional aggregates, especially for aggregation‐induced emission (AIE) system. In this review, recent progress some basic novel forms, coassembled presenting distinctive optical features, such waveguide polarization emission, polymorph‐dependent stimuli‐responsive luminescence presented. The systematic insight into relationship between property is discussed. Guidelines therefore anticipated will direct future preprogramming design so fine‐tune feature through a specific developing organic with desirable properties.

Language: Английский

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Recent Progress in Pure Organic Room Temperature Phosphorescence of Small Molecular Host–Guest Systems

ACS Materials Letters, Journal Year: 2021, Volume and Issue: 3(4), P. 379 - 397

Published: March 15, 2021

Organic room temperature phosphorescence (RTP) materials have been used in high resolution imaging and anticounterfeiting due to their long lifetime of ability avoid interference from autofluorescence excitation light. An important factor when considering is the constant intersystem crossing (ISC) process. It great importance develop novel pure organic RTP via precise manipulation ISC process nonradiative decay rate. Encapsulation a luminophore host matrix can quenching caused by presence water oxygen, while increasing intermolecular interaction suppress decay. Compared with polymeric supramolecular matrixes, small molecular matrixes provide possible orbitals facilitate enhance emission. Herein, recent progress made using mechanisms realizing emission are summarized. The design principles as well applications based on host–guest system also revealed. Finally, future prospects involving systems proposed.

Language: Английский

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Stimulus-Responsive Room Temperature Phosphorescence Materials: Internal Mechanism, Design Strategy, and Potential Application

Accounts of Materials Research, Journal Year: 2021, Volume and Issue: 2(8), P. 644 - 654

Published: July 26, 2021

ConspectusRoom temperature phosphorescence (RTP) materials, which could respond to external stimuli, such as force, heat, light, electric filed, etc., have drawn increasing attention for their broad application prospects, especially in the fields of anticounterfeiting, sensors, data storage, and so on. In comparison with traditional fluorescence ones, RTP materials show much longer emission lifetimes, can be even caught by naked eye. Thus, change lifetime under an stimulus also a potential monitoring parameter, addition color intensity. other words, number visual parameters increase from two three would greatly facilitate practical applications. Until now, been typically limited metal-containing inorganic particularly rare-earth phosphors. Their emissions are governed slow liberation trapped charge carriers isolated traps impurities, defects, or ions through thermal stimulation low luminescence efficiency. However, these suffer some intrinsic disadvantages, including high cost, toxicity, instability aqueous environments. order solve problems, purely organic should good choice. kinds really scarce ones response characteristic.To develop effect, we scientists tried lot. Luckily, progresses made. this Account, present our recent progress on stimulus-responsive room mainly focusing internal mechanism First, fundamental knowledge is described illustrate importance main principles effect. Then, typical based different mechanisms discussed. Mainly, were introduced, namely, single-component multicomponent ones. Correspondingly, dynamic property occurred distinct mechanisms. For changes molecular structure, packing, conformation, played significant role corresponding As changed oxygen concentration matrix intermolecular distance between components found more during process. Accordingly, applications explored processes. With classification mechanisms, design strategy well proposed, thus guiding further development research field.

Language: Английский

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Through-Space Interactions in Clusteroluminescence

JACS Au, Journal Year: 2021, Volume and Issue: 1(11), P. 1805 - 1814

Published: Sept. 30, 2021

Conventional π-conjugated luminophores suffer from problems such as emission quenching, biotoxicity, environmental pollution, etc. The emerging nonconjugated and nonaromatic clusteroluminogens (CLgens) are expected to overcome these stubborn drawbacks, so research of CLgens shows great significance not only for practical application but also the construction fundamental photophysical theories. This perspective summarizes unusual features in comparison traditional chromophores, molecular structures, unmatched absorption excitation, excitation-dependent luminescence, multiple peaks, room-temperature phosphorescence. Different theory through-bond conjugation luminophores, through-space interactions, including n···n interaction n···π interaction, regarded emitting sources CLgens. In addition, formation network clusters is proposed an efficient strategy improve performance CLgens, their potential applications anticounterfeiting, photoelectronic devices, bioimaging prospected.

Language: Английский

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Realizing Record‐High Electroluminescence Efficiency of 31.5 % for Red Thermally Activated Delayed Fluorescence Molecules

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(44), P. 23635 - 23640

Published: Aug. 30, 2021

Tailor-made red thermally activated delayed fluorescence (TADF) molecules comprised of an electron-withdrawing pyrazino[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile core and various electron-donating triarylamines are developed. They can form intramolecular hydrogen-bonding, which is conducive to improving emission efficiency promoting horizontal orientation show near infrared (NIR) emissions (692-710 nm) in neat films (606-630 with high photoluminescence quantum yields (73-90%) doped films. prefer large dipole ratios films, rendering optical out-coupling factors (0.39-0.41). Their non-doped OLEDs exhibit NIR lights (716-748 maximum external efficiencies (ηext,max ) 1.0-1.9%. And their radiate (606-648 achieve record-beating ηext,max up 31.5%. These new TADF materials should have great potentials display lighting devices.

Language: Английский

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