Room temperature phosphorescence materials based on small organic molecules: Design strategies and applications

Deleted Journal, Год журнала: 2024, Номер 2(3)

Опубликована: Июль 23, 2024

Abstract Room‐temperature phosphorescence (RTP) materials have attracted significant attention due to their applications in various fields such as information storage and encryption, organic light‐emitting diode (OLED), sensing, lighting display, biological imaging, photodynamic therapy. Traditionally, RTP can be efficiently developed using inorganic systems with noble metals or rare earth elements. Recently, many efforts been devoted the development of based on small molecules. The strategies construct include hydrogen bonding, heavy atom effect, n –π* transitions, π–π stacking, donor–acceptor host–guest doping. Herein, we summarize recent examples molecules primarily focusing design properties. Moreover, promising OLED, well bio‐imaging phototherapy are discussed. challenges perspectives given provide inspiration toward future materials.

Язык: Английский

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Conformational Effect of Catechol-Terephthalonitrile Emitters Leading to Ambient Violet Phosphorescence

The Journal of Physical Chemistry A, Год журнала: 2024, Номер 128(3), С. 581 - 589

Опубликована: Янв. 11, 2024

Organic ambient violet phosphorescent (AVP) materials are of great interest due to their involvement high energy and longer-lived triplet excitons. Here, we show three fused ring functionalized donor–acceptor–donor (D–A–D/D–A–D′) emitters (BPT1–BPT3), in which two catechol-based donors (3,4-dihydroxybenzophenone, catechol, or 3,5-ditert-butylcatechol) covalently the terephthalonitrile acceptor via four O–C single bonds. Spectroscopic analysis revealed that all molecules AVP (∼390–394 nm, τAVP = 73–101 μs) with phosphorescence quantum yields (ϕP) 1.8–27.4% low singlet–triplet gaps (0.036–0.046 eV) conformational effects. BPT3 bulky tert-butyl groups increases (ϕP 27.4%). Quantum chemistry calculations reveal flat (F1) twisted (F2) conformers (ground state) a difference (∼4–5 kcal/mol) for molecules; F1 conformer is responsible efficient AVP, while weak blue thermally activated delayed fluorescence components realized from F2 conformer. This approach may provide important clues design high-energy organic materials.

Язык: Английский

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White Light Emission via Dual Thermally Activated Delayed Fluorescence from a Single-Component Phenothiazines–Diphenyl Quinoline Conjugate

The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер 15(11), С. 3135 - 3141

Опубликована: Март 13, 2024

White light emission (WLE) via dual thermally activated delayed fluorescence (TADF) from a single-component-based organic system remains challenging as result of the difficulty in design. Here, we introduce conformational isomerization approach to achieve WLE twisted donor–acceptor (PTzQP1) that comprises two phenothiazines covalently attached 6,8-isomeric positions 2,4-diphenyl quinoline C–N single bonds. Spectroscopic studies and quantum chemistry calculations revealed PTzQP1 shows simultaneous blue TADF orange covering visible range (420–800 nm) with photoluminescence yield 45 ± 2% Commission Internationale de l'Éclairage (CIE) coordinates 0.30, 0.33. The features high rates reverse intersystem crossing (kRISC1 = 1.38 × 107 0.24 s–1 kRISC2 5.04 106 0.32 s–1) are realized low singlet–triplet gaps (S1EQ–T1EQ 0.04 eV S1QA–T1QA 0.05 eV) quasi-axial (QA) quasi-equatorial (QE) conformers. This finding is expected provide new direction for designing high-energy-efficient emitters.

Язык: Английский

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First-principles design of heavy-atom-free singlet oxygen photosensitizers for photodynamic therapy

The Journal of Chemical Physics, Год журнала: 2024, Номер 160(16)

Опубликована: Апрель 28, 2024

In photodynamic therapy (PDT) treatment, heavy-atom-free photosensitizers (PSs) are a great source of singlet oxygen photosensitizer. Reactive species (ROS) produced by an energy transfer from the lowest triplet excited state to molecular cancer cells. To clarify photophysical characteristics in states few experimentally identified thionated (>C=S) molecules and their oxygenated congeners (>C=O), quantum chemical study is conducted. This illustrates properties that render them unsuitable for PDT treatment. Concurrently, hierarchy presented based on utility lowest-energy excitons compounds. Their non-radiative decay rates calculated reverse-ISC inter-system crossover (ISC) processes. addition, vibronic importance C=O C=S bonds clarified computation Huang–Rhys factor, effective vibrational mode, reorganization inside Marcus–Levich–Jörtner system. ROS generation PSs exceeds as kf ≪ kISC, where radiative rate designated kf. As result, current work offers strategy analyzing effectiveness PDT.

Язык: Английский

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Effect of Thermally Reversible Conformers on Delayed Fluorescence and Temperature Sensing

The Journal of Physical Chemistry C, Год журнала: 2024, Номер 128(21), С. 8750 - 8758

Опубликована: Май 16, 2024

Achieving thermally enhanced delayed emission (TEDE) through reversible conformational changes in organic conjugate acid–base pairs poses significant challenges the design process. Here, we present a novel approach utilizing isomerization to attain TEDE from three distinct twisted donor–acceptor conjugates (PTzQF, PTzQCl, and PTzQBr). These feature phenothiazine covalently linked 8-position of quinoline segment via C–N single bond, with 4-fluorophenyl, 4-chlorophenyl, 4-bromophenyl substituents at 2,4-positions naphthyl unit 8-position. Through detailed spectroscopic studies quantum chemistry calculations, unveil that doped within host [1,3-bis(N-carbazolyl)benzene] (mCP) exhibit luminescence, involving both locally excited (LE) guest charge transfer (CT) emissions. Upon heating, luminescence quenching effect occurs on violet LE emission, while orange fluorescence (DF) experiences enhancement elevated temperatures ranging 10 350 K. Conversely, cooling triggers reversal back emission. The induced change guests leads modulation DF due slight energy difference between conformers (7.64 kcal/mol). Meanwhile, control nonradiative transitions during heating (350 K) (10 influences band. Employing ratiometric response (RLR) blended films, devise RLR-thermometers showcasing absolute relative sensitivities 0.06973 0.52839 0.017 0.025%, temperature resolutions 0.0012 0.063 this study, aim provide insights into sensing host–guest modulation.

Язык: Английский

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Shaking Up the Friedländer Reaction: Rapid, Scalable Mechanochemical Synthesis of Polyaryl‐substituted Quinolines

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Авг. 16, 2024

Abstract Quinolines are ubiquitous heterocyclic aromatic scaffolds, which can be found in many natural and synthetic products. They highly valued for their pharmacological electrochemical properties, encouraging the discovery of new routes quinoline synthesis diversification. In particular, polyaryl‐substituted quinolines have recently surged as useful substrates a wide variety applications, yet remain difficult inefficient. Herein, we report rapid novel mechanochemical Friedländer under basic conditions using ball milling. The optimized reaction resulted moderate to excellent yields ranging from 48% >95% demonstrated broad functional group tolerance at 1 hour times. We further show route photocatalyst DPQN 2,4−di−OMe photo‐ligand PPQN well OLED donor‐acceptor pCzPPQ, electron transport material oligoquinoline TQB organic semiconductor DPA. A gram scale was also achieved Resonant Acoustic Mixing (RAM), providing an isolated yield 87% after simple recrystallization ethanol.

Язык: Английский

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Carbazole–Benzonitrile–Norbornadiene Conjugates for Photothermally Reversible Ambient Phosphorescence

The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер 15(11), С. 3191 - 3196

Опубликована: Март 14, 2024

Organic photoswitches have attracted significant attention across various fields, such as sensing, bioimaging, photopharmacology, molecular machines, and solar energy storage. However, a result of design complexities, achieving photothermally reversible ambient phosphorescence switching in the condensed state remains elusive. Herein, we explore impact norbornadiene (NBD)/quadricyclane (QC) substitution at position 5 benzonitrile acceptor covalently attached to carbazole donor on luminescence switching. Experimental investigations demonstrated that CzN TBCzN switches exhibited fluorescence solution. Moreover, state, were observed low singlet–triplet (ΔEST) gap (CzN ⇆ CzQ, ΔESTCzN/CzQ = 0.05/0.28 eV; TBCzQ, ΔESTTBCzN/TBCzQ 0.06/0.09 eV). Reversible is primarily influenced by modulation conjugation resulting from NBD QC This approach may provide important clues for visible-light-absorbing phosphorescent materials.

Язык: Английский

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Mixed Emission of Acenaphtho[1,2-b] Quinoxaline Regioisomers

The Journal of Physical Chemistry C, Год журнала: 2025, Номер unknown

Опубликована: Янв. 20, 2025

Язык: Английский

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Modulated dual photo/electro luminescence via molecular engineering of Ds-A-Dw type TADF materials

Chemical Engineering Journal, Год журнала: 2024, Номер unknown, С. 156529 - 156529

Опубликована: Окт. 1, 2024

Язык: Английский

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Achieving Ultralong Room-Temperature Phosphorescence Via Single-Bond Locking Planarization Strategy

ACS Materials Letters, Год журнала: 2024, Номер 6(12), С. 5384 - 5391

Опубликована: Ноя. 8, 2024

Ultralong room-temperature phosphorescence (URTP) materials have been widely studied due to their broad applications. However, achieving phosphorescent with ultralong lifetimes is engaging and challenging. In this work, the indolo[3,2,1-j,k]carbazole (ICZ) excellent planarity obtained through twice single-bond locking on triphenylamine (TPA). Doping ICZ into a rigid matrix, URTP lifetime of 3.24 s photoluminescence quantum yield 37.37% successfully prepared.. The analysis single-crystal, temperature-dependent photophysical characterization, Huang–Rhys factor, theoretical calculations demonstrates that it possible make molecules more planar by locking, which can inhibit structural relaxation excited state thus reduce nonradiative transition generate URTP. addition, we achieve full-color afterglow energy transfer. potential applications anticounterfeiting optoelectronic information display these conducted. This work an important reference for construction materials.

Язык: Английский

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