How the Length of Through‐Space Conjugation Influences the Clusteroluminescence of Oligo(Phenylene Methylene)s

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(8)

Published: Jan. 2, 2024

The length and mode of conjugation directly affect the molecular electronic structure, which has been extensively studied in through-bond (TBC) systems. Corresponding research greatly promotes development TBC-based luminophores. However, how through-space (TSC), one kind weak interaction, influence photophysical properties non-conjugated luminophores remains a relatively unexplored field. Here, we unveil non-linear relationship between TSC emission characteristics systems, contrast to reported proportional correlation TBC More specifically, oligo(phenylene methylene)s (OPM[4]-OPM[7]) exhibit stronger prominent blue clusteroluminescence (CL) (≈440 nm) compared shorter counterparts (OPM[2] OPM[3]). OPM[6] demonstrates highest solid-state quantum yield (40 %), emphasizing importance balancing flexibility rigidity. Further theoretical calculations confirmed that CL these was determined by stable derived from inner rigid Diphenylmethane (DPM) segments within oligomers instead outer ones. This discovery challenges previous assumptions adds new dimension understanding TSC-based

Language: Английский

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Excited-State Odd–Even Effect in Through-Space Interactions

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(38), P. 21104 - 21113

Published: Sept. 15, 2023

The odd-even effect is a fantastic phenomenon in nature, which has been applied diverse fields such as organic self-assembled monolayers and liquid crystals. Currently, the origin of each remains elusive, all reported effects are related to ground-state properties. Here, we discover an excited-state through-space interaction (TSI) nonconjugated tetraphenylalkanes (TPAs). TPAs with even number alkyl carbon atoms (C2-TPA, C4-TPA, C6-TPA) show strong TSI, long-wavelength emission, high QY. However, odd ones (C1-TPA, C3-TPA, C5-TPA, C7-TPA) almost nonexistent negligible Systematically experimental theoretical results reveal that synthetically determined by three factors: geometry, molecular movability, intermolecular packing. Moreover, these flexible luminescent possess tremendous advantages fluorescent information encryptions. This work extends photophysics, demonstrating its substantial importance universality nature.

Language: Английский

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Resorcinol‐Phthalaldehyde Resins for Photosynthesis of Hydrogen Peroxide: Modulation of Electronic Structure and Integration of Dual Channel Pathway

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(33)

Published: May 9, 2024

Abstract Modulating of electronic structure photocatalyst and integration dual channel pathway are promising strategy for efficient photosynthesis hydrogen peroxide (H 2 O ) from pure water without sacrificial agent oxygen exposure. In this work, nontoxic aromatic dialdehyde is used to replace the commonly toxic formaldehyde form resorcinol‐phthalaldehyde resins through a hydrothermal method. The introducing ring as π spacer increases separation distance electrons holes avoid their recombination. H can be produced via integrated reduction reaction (ORR) oxidation (WOR) due suitable energy band positions spatially separated sites. Resorcinol‐p‐phthalaldehyde (RP) resin exhibits yield 3351 µmol g −1 h with high apparent quantum (AQY) 14.9% at 420 nm solar‐to‐chemical conversion (SCC) efficiency 1.54%. This work provides simple modulate charge redox on molecular level design.

Language: Английский

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Recent Progress in Nonconventional Luminescent Macromolecules and their Applications

Macromolecules, Journal Year: 2024, Volume and Issue: 57(12), P. 5561 - 5577

Published: June 11, 2024

Traditional π-conjugated luminescent macromolecules typically suffer from aggregation-caused quenching (ACQ) and high cytotoxicity, they require complex synthetic processes. In contrast, nonconventional (NCLMs) with nonconjugated structures possess excellent biocompatibility, ease of preparation, unique luminescence behavior, emerging applications in optoelectronics, biology, medicine. NCLMs are currently believed to produce inherent due through-space conjugation overlapping electron orbitals solid/aggregate states. However, as experimental facts continue exceed expectations or even overturn some previous assumptions, there is still controversy about the detailed luminous mechanism NCLMs, extensive studies needed further explore mechanism. This Perspective highlights recent progress classifies summarizes these advances viewpoint molecular design, exploration, applications, challenges prospects. The aim provide guidance inspiration for huge fundamental practical potential NCLMs.

Language: Английский

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Phosphine-Capped Effects Enable Full-Color Clusteroluminescence in Nonconjugated Polyesters

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(15), P. 10889 - 10898

Published: April 8, 2024

Full-color luminophores have advanced applications in materials and engineering, but constructing color-tunable clusteroluminescence (CL) from nonconjugated polymers based on through-space interactions remains a huge challenge. Herein, we develop phosphine-capped polyesters exhibiting blue-to-red CL (400–700 nm) phosphine-initiated copolymerization of epoxides cyclic anhydrides, especially P1-0.5TPP, which exhibits red (610 with high quantum yield 32%. Experiments theoretical calculations disclose that the effect brings about conformational changes induces phosphine–ester clusters by (n,π*) interactions. Moreover, colors efficiencies can be easily tailored types phosphines, compositions structures polyesters, concentration. Significantly, role polymer motions (group, segmental, chain motions) originating microregions inside is revealed. Further, are demonstrated to dyes fluorescent fibers also used for multicolor light-emitting diodes including white light. This work not only provides an engineering strategy end-group prepare full-color clusteroluminogens broadens prospects material applications.

Language: Английский

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Narrowband clusteroluminescence with 100% quantum yield enabled by through-space conjugation of asymmetric conformation

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 30, 2024

Different from traditional organic luminescent materials based on covalent delocalization, clusteroluminescence nonconjugated luminogens relies noncovalent through-space conjugation of electrons. However, such spatial electron delocalization is usually weak, resulting in low efficiency and board emission peak due to multiple vibrational energy levels. Herein, several are constructed by employing biphenyl as the building unit reveal structure-property relationship solve current challenges. The intramolecular can be gradually strengthened introducing units stabilized rigid molecular skeleton intermolecular interactions. Surprisingly, narrowband with full width at half-maximum 40 nm 100% successfully achieved via an asymmetric conformation, exhibiting comparable performance conjugated luminogens. This work realizes highly efficient highlights essential role structural conformation manipulating photophysical properties unconventional materials.

Language: Английский

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Near‐Infrared Emission Beyond 900 nm from Stable Radicals in Nonconjugated Poly(diphenylmethane)

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(24)

Published: April 9, 2024

Organic radicals with narrow energy gaps are highly sought-after for the production of near-infrared (NIR) fluorophores. However, current repertoire developed organic is notably limited, facing challenges related to stability and low fluorescence efficiency. This study addresses these limitations by achieving stable in nonconjugated poly(diphenylmethane) (PDPM). Notably, PDPM exhibits a well-balanced structural flexibility rigidity, resulting robust intra-/inter-chain through-space conjugation (TSC). The within PDPM, coupled strong TSC, yield remarkable full-spectrum emission spanning from blue NIR beyond 900 nm. extensive tunability achieved through careful adjustments concentration excitation wavelength. findings highlight efficacy polymerization stabilizing introduce novel approach developing emitters based on triphenylmethane subunits.

Language: Английский

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Tailoring the Dynamics of Excited‐State Charge Transfer through Conformational Engineering to Improve Second Near‐Infrared Fluorescence for High‐Resolution Osteosarcoma Imaging

Small Structures, Journal Year: 2024, Volume and Issue: 5(5)

Published: Feb. 5, 2024

The dynamics of excited‐state charge transfer (CT) in second near‐infrared (NIR‐II) fluorophore proceeds with conformational change that govern fluorescence. Unveiling the relationship between CT and excited state is great fundamental significance optimizing NIR‐II fluorescence but remains less explored. This study unveils pivotal role large promoting evolution emissive into nonemissive (CA‐BBT). Spectroscopic computational results reveal rotation/twisting leads to a pronounced increase character state. heightened CA‐BBT enables rapid within 1.4 ps, as observed by ultrafast spectroscopy. Subsequently, this dominates nonradiative decay, resulting very low Preventing such detrimental constraining 10‐fold enhancement fluorescence, enabling high‐resolution dynamic visualization vasculature osteosarcoma. offers profound understanding changes presenting innovative perspectives develop bright fluorophores.

Language: Английский

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A Self‐Assemble Supramolecular Film with Humidity Visualization Enabled by Clusteroluminescence

Advanced Science, Journal Year: 2023, Volume and Issue: 11(1)

Published: Nov. 9, 2023

Abstract Clusteroluminescence (CL) has recently gained significant attention due to its unique through‐space interactions associated with a high dependence on the aggregation of subgroups. These distinct features could easily transform stimuli into visual fluorescence and monitor fluctuation environment but have not received sufficient before. In this work, supramolecular films are designed based neutralization reaction anhydride groups self‐assembly dynamic covalent disulfide bonds in NaOH aqueous solution. The hydrophilic carboxylate chromophores hydrophobic disulfide‐containing five‐membered rings be observed by variation state CL. Furthermore, cross‐linking obtained water‐sensitive alter distance stimulated surrounding water vapor, causing emission wavelength change from 534 508 nm varying relative humidity. This work only provides an approach clusteroluminogens also offers new strategies for designing stimuli‐responsive materials that utilize intrinsic

Language: Английский

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Spring Lock: Constructing Cluster Emitters with Colorful TADF from Non‐Conjugated Polymaleimide Helical Chains

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(38)

Published: April 9, 2024

Abstract Non‐conjugated luminescent polymers have received much attention due to their excellent flexibility, processability, and biocompatibility. However, the single emission color low solid‐state luminescence efficiency restrict further development. Herein, by introducing carboxyl‐terminated alkyl chains on rigid helical polymaleimide backbone, a series of non‐conjugated are designed synthesized. Due “spring lock” formed synergism scalable main flexible side chains, these exhibit effective cluster with thermally activated delayed fluorescence (TADF) property, thereby significantly improving quantum yield up 59.6%. The TADF wavelengths polymer powders can be tuned from 498 639 nm through changing reaction solvents, because conformation forming clusters is sensitive solvent polarity. Interestingly, metal ions induce construct self‐repairing gels, which show potential applications in ammonia detection information encryption. This work not only provides an design strategy for colorful high‐efficiency TADF, but also reveals mechanism enlightens promising gels.

Language: Английский

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