Recent Advances in Narrow Emission Bandwidth Materials for Application in Organic Light‐Emitting Diodes

Advanced Optical Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 21, 2025

Abstract The preparation of narrow emission bandwidth materials is crucial for the development advanced organic light‐emitting diodes (OLEDs). In this review article, state‐of‐the‐art methodologies used emitters with high color purity are summarized, and favorable design strategies rationally organized. Currently OLEDs have some issues, such as device stabilization that must be resolved, should also considered. Given recent exponential growth in number types narrowband emissive organometallic complexes exhibiting multiple‐resonance thermally activated delayed fluorescence metal‐to‐ligand charge transfer characteristics, there an urgent need to establish key technology descriptors purity. review, developments boron, fused indolocarbazole, carbonyl, phosphine oxide, exhibit spectra described, future directions advance performance devices suggested.

Language: Английский

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Achieving Narrowband and Stable Pure Blue Organic Light‐Emitting Diodes by Employing Molecular Vibration Limited Strategies in the Extended π‐Conjugated Indolocarbazole Skeleton

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract B‐ and N‐heterocyclic fluorophores have reveal promising efficiency in blue organic light‐emitting diodes (OLEDs) with small full‐width‐at‐half‐maximum (FWHM). However, their structural determinants for spectral broadening operating stability are still needed to be investigated further. Herein, a novel multi‐N‐heterocycles Diindolo[3,2,1jk:3′,2′,1′jk]dicarbazole[1,2‐b:4,5‐b] (DIDCz) is proposed manipulate the emission color toward pure region by extending π‐conjugation of N‐π‐N bridge. By utilizing computed technique, interrelationships between indolocarbazole (ICz)‐cyclization sites defined. Molecular backbone modifications involving optimized 2,3,6,7‐ICz cyclization steric hindrance substituents conducive restricting swing peripheral bonds stretching resonances polycyclic aromatic hydrocarbon (PAH) frameworks, thereby contributing reduction shoulder peaks. Consequently, DIDCz‐based chromophore exhibited narrowband FWHM only 15 nm, achieving highly efficient (external quantum efficiencies 8.87% triplet–triplet fusion fluorescence 22.3% sensitized fluorescence) long‐term (95% initial luminance 1000 cd m −2 , T95 = 1545 h) electroluminescence performances, showing one most stable OLEDs among reported PAH chromophores. The current achievements offer new perspective manage precisely based on molecular vibration limiting technique.

Language: Английский

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Efficient narrowband yellow organic light-emitting diodes based on iridium(III) complexes with rigid indolo[3,2,1-jk]carbazole unit

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(29), P. 12199 - 12207

Published: Jan. 1, 2024

Two yellow Ir( iii ) complexes based on the main ligands containing rigid indolo[3,2,1- jk ]carbazole and thiazole units show high efficiencies with narrow emission. And OLEDs good performances an EQE max of up to 25.2% a FWHM 31 nm.

Language: Английский

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NHC-Based Deep-Red Phosphorescent Iridium Complexes Featuring Three-Charge (0, −1, −2) Ligands

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 22, 2025

N-heterocyclic carbene (NHC)-based phosphorescent iridium complexes have attracted extensive attention due to their good optical properties and high stability in recent years. However, currently reported NHC-based can easily achieve emission of blue, green, or even ultraviolet light, while red deep-red light is relatively rare. Here, we report a new family (Ir1, Ir2, Ir3, Ir4) featuring three-charge (0, -1, -2) ligands. The single-crystal structures confirm that all exhibit trans-C-N configuration between the NHC carbon atom monoanionic (-1) ligand nitrogen neutral (0) there are abundant intermolecular intramolecular interactions crystalline state. Notably, exhibited an effective (650-664 nm). Moreover, (Ir2 based on benzimidazol-2-ylidene (pmb) higher efficiency longer lifetime than corresponding (Ir1 Ir2) imidazol-2-ylidene (pmi), respectively. Density functional theory calculations demonstrate pmb Ir3 Ir4 more involved excited state pmi Ir1 which caused by stronger electron-donating ability ligand. Considering better properties, Ir2 were eventually used as dopant emitters light-emitting diode (OLED) devices obtain maximum external quantum (8.5 10.1%) region (628 624 nm) with Commission Internationale deL'Eclairage (CIE) coordinates (0.65, 0.34) (0.63, 0.36), respectively, low turn-on voltage (2.4 V). This research provides important idea for design optoelectronic applications complexes.

Language: Английский

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Doubling the efficiency of solution-processed blue phosphorescent organic light-emitting diodes via modified PEDOT : PSS hole-injection layers

Journal of Materials Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

High performance blue phosphorescent organic light-emitting diodes (OLEDs) with a modified PEDOT : PSS structure were obtained by utilizing TCTA POPH interfacial exciplex.

Language: Английский

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Circularly polarized narrowband phosphorescent organic light-emitting diodes

Dalton Transactions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Two narrowband chiral iridium isomers with an FWHM of 48 nm, EQE max 15.58% and g EL 2.29 × 10 −4 were synthesized separated.

Language: Английский

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Selective Deuteration-Enhanced Phosphorescent Performance in Square-Planar Tetradentate Pt(II) Complexes: Unveiling the Role of Vibration Coupling in Electronic Transitions

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 24, 2025

Deuteration enhances the organic light-emitting diode (OLED) stability and performance. Theoretical calculations on square-planar tetradentate Pt(II) complexes show that deuteration exerts no electronic effects because deuterium has same number of electrons as hydrogen. Consequently, equilibrium structures (ground/excited states), frontier molecular orbital (FMO) distributions energy levels, natural transition orbitals (NTOs), spin-orbital coupling (SOC) remain unchanged. Deuteration-doubled mass lowers vibrational frequencies, reducing levels zero-point (ZPE) by about 2.08 kcal/mol per deuteration, while slightly affecting 0-0 (E0-0) reorganization energy. Frequency reduction suppresses nonradiative decay rates (knr), boosting photoluminescence quantum yield (PLQY). Analyses Huang-Rhys factors (S) Franck-Condon (FC) significant changes in mid-to-high-frequency particle hole. Altered wave functions enhance Herzberg-Teller (HT) dipole moment, radiative (kr). Selective Cz ring effectively increases kr, knr, modulates fine structure spectrum, comparable to perdeuteration. C-D bond chemical degradation rate is 3.94 times slower than C-H, further improving stability. These results establish a framework for optimizing emitters extending OLED operating lifetimes.

Language: Английский

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Effect of anchoring groups on the photocatalytic performance of iridium(III) complexes in hydrogen production and their toxicological analysis

Physical Chemistry Chemical Physics, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Three iridium( iii ) complexes (Ir1–Ir3) with different anchoring moieties were designed, synthesised and used as photosensitisers for water-splitting hydrogen generation.

Language: Английский

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Spectroscopic and Electrochemical Insights into Strategies Tuning Red-Green-Blue (RGB) Electrochemiluminescence from a Single Ruthenium Complex

The Journal of Physical Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: May 24, 2025

Language: Английский

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Engineering emissive excited states in organic electroluminescent materials

Matter, Journal Year: 2025, Volume and Issue: 8(6), P. 102142 - 102142

Published: June 1, 2025

Language: Английский

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