Thermally Activated Delayed Fluorescence and Beyond. Photophysics and Material Design Strategies. DOI Creative Commons
Hartmut Yersin, Uwe Monkowius

Advanced Photonics Research, Год журнала: 2024, Номер unknown

Опубликована: Сен. 2, 2024

This review focuses on thermally activated delayed fluorescence (TADF). Photophysical properties of Cu(I) complexes and unique organic molecules are addressed. Investigations, based temperature‐dependent emission studies, micro‐ to femto‐second time‐resolved spectroscopy investigations, quantum mechanical considerations, state‐of‐art calculations, light‐emitting diodes (OLED) device address exciton harvesting mechanisms photophysical impact the energy gap Δ E ( S 1 – T ) spin‐orbit coupling (SOC). We disclose relationship between (i) transition rate k 0 ); (ii) SOC, phosphorescence, intersystem crossing (ISC); (iii) internal/external rigidity, luminescence yield, excitation self‐trapping, concentration quenching; (iv) environment polarity state tuning, as well (v) SOC combined ambient‐temperature TADF/phosphorescence, zero‐field splitting, spin‐lattice relaxation (at = 1.2 K). These studies guide us milestone complexes. Moreover, we demonstrate that fast ISC in requires mixing with an additional, energetically close triplet state. Thus, a structure for TADF ultra‐fast reverse‐ISC rates (>10 9 s −1 )<10 cm (<1 meV) is presented allowing singlet‐triplet equilibrated sub‐microsecond decay. First OLEDs fabricated show high external efficiency ≈19%. Based this breakthrough material class, new mechanism, direct singlet (DSH), presented.

Язык: Английский

Methacrylate-based copolymers as tunable hosts for triplet–triplet annihilation upconversion DOI Creative Commons
Michael J. Bennison, Abigail Collins, Larissa Gomes Franca

и другие.

Materials Advances, Год журнала: 2025, Номер 6(3), С. 1089 - 1096

Опубликована: Янв. 1, 2025

The ability to convert light higher energies through triplet-triplet annihilation upconversion (TTA-UC) is attractive for a range of applications including solar energy harvesting, bioimaging and anti-counterfeiting. Practical require integration the TTA-UC chromophores within suitable host, which leads compromise between high efficiencies achievable in liquids durability solids. Herein, we present series methacrylate copolymers as hosts, glass transition temperature (T g), hence efficiency can be tuned by varying co-monomer ratios (n-hexyl (HMA) 2,2,2-trifluoroethyl (TFEMA)). Using model sensitiser/emitter pair palladium(ii) octaethylporphyrin (PdOEP) diphenylanthracene (DPA), quantum yield was found increase with decreasing temperature, reaching maximum 1.6 ± 0.2% air at room temperature. Kinetic analysis phosphorescence decays reveal that increased PdOEP aggregation glassy polymers competitive non-radiative relaxation pathway quenches triplet state. Notably, threshold intensity highly sensitive ranging from 1250 mW cm-2 PHMA90TFEMA10 g = -9.4 °C) ∼200 more 'glassy' e.g. PHMA33TFEMA67 20.1 °C), suggesting mechanism switches diffusion-based collisions exciton migration localised sensitiser-emitter pairs.

Язык: Английский

Процитировано

0
Synthesis, photophysical properties and DFT calculation of four novel iridium(III) complexes based on dibenzothiophene DOI
Mengyun Wang, Bichu Cheng, Mengting Zhao

и другие.

Inorganica Chimica Acta, Год журнала: 2025, Номер unknown, С. 122562 - 122562

Опубликована: Янв. 1, 2025

Язык: Английский

Процитировано

0
Thermally activated delayed fluorescence materials: innovative design and advanced application in biomedicine, catalysis and electronics DOI Creative Commons
Ehsan Ullah Mughal,

Syeda Fariha Kainat,

Abdulaziz M. Almohyawi

и другие.

RSC Advances, Год журнала: 2025, Номер 15(10), С. 7383 - 7471

Опубликована: Янв. 1, 2025

Thermally Activated Delayed Fluorescence (TADF) materials have emerged as a revolutionary class of functional compounds, driven by their unique ability to utilize excitons from both singlet and triplet states for efficient fluorescence emission. This manuscript provides an overview recent innovations in TADF material design, focusing on molecular strategies achieve optimal properties, including small singlet-triplet energy gaps (ΔE ST) high photoluminescence quantum yields. We explore the diverse applications materials, spanning OLEDs, biomedical imaging, photosensitizers, photocatalysis, UV photodetectors (UVOPDs), electrogenerated chemiluminescence, triplet-triplet annihilation (TTA) sensitizers, organic hybrid microwire radial heterojunctions, multicolor luminescent micelles, mechano-luminescence (ML), light-emitting electrochemical cells (LEECs), fluorescent probes. The integration these technologies highlights potential enhance performance efficiency. Through this review, we aim elucidate fundamental principles governing behavior present forward-looking perspective synthetic methodologies new, versatile materials.

Язык: Английский

Процитировано

0
Carbazolylphenyl ethynyl anthracenes as TTA emitters with improved horizontal alignment for the applications in OLEDs and for optical detection of the nitroaromatic explosive compounds DOI
Oleksandr Bezvikonnyi, Pavel Arsenyan,

Alla Petrenko

и другие.

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy, Год журнала: 2025, Номер unknown, С. 126127 - 126127

Опубликована: Март 1, 2025

Язык: Английский

Процитировано

0
Thermally Activated Delayed Fluorescence and Beyond. Photophysics and Material Design Strategies. DOI Creative Commons
Hartmut Yersin, Uwe Monkowius

Advanced Photonics Research, Год журнала: 2024, Номер unknown

Опубликована: Сен. 2, 2024

This review focuses on thermally activated delayed fluorescence (TADF). Photophysical properties of Cu(I) complexes and unique organic molecules are addressed. Investigations, based temperature‐dependent emission studies, micro‐ to femto‐second time‐resolved spectroscopy investigations, quantum mechanical considerations, state‐of‐art calculations, light‐emitting diodes (OLED) device address exciton harvesting mechanisms photophysical impact the energy gap Δ E ( S 1 – T ) spin‐orbit coupling (SOC). We disclose relationship between (i) transition rate k 0 ); (ii) SOC, phosphorescence, intersystem crossing (ISC); (iii) internal/external rigidity, luminescence yield, excitation self‐trapping, concentration quenching; (iv) environment polarity state tuning, as well (v) SOC combined ambient‐temperature TADF/phosphorescence, zero‐field splitting, spin‐lattice relaxation (at = 1.2 K). These studies guide us milestone complexes. Moreover, we demonstrate that fast ISC in requires mixing with an additional, energetically close triplet state. Thus, a structure for TADF ultra‐fast reverse‐ISC rates (>10 9 s −1 )<10 cm (<1 meV) is presented allowing singlet‐triplet equilibrated sub‐microsecond decay. First OLEDs fabricated show high external efficiency ≈19%. Based this breakthrough material class, new mechanism, direct singlet (DSH), presented.

Язык: Английский

Процитировано

2