Organoboron-based multiple-resonance emitters: synthesis, structure–property correlations, and prospects

Chemical Society Reviews, Год журнала: 2024, Номер 53(3), С. 1624 - 1692

Опубликована: Янв. 1, 2024

This review highlights organoboron-based multiple-resonance compounds’ synthetic strategies classified as one-pot borylation, one-shot and late-stage functionalisation, explores material structure–photophysical property correlations.

Язык: Английский

---

BN‐Bond‐Embedded Triplet Terpolymers with Small Singlet–Triplet Energy Gaps for Suppressing Non‐Radiative Recombination and Improving Blend Morphology in Organic Solar Cells

Advanced Materials, Год журнала: 2023, Номер 35(17)

Опубликована: Фев. 3, 2023

Suppressing the photon energy loss (Eloss ), especially non-radiative loss, is of importance to further improve device performance organic solar cells (OSCs). However, typical π-conjugated semiconductors possess a large singlet-triplet gap (ΔEST leading lower triplet state than charge transfer and contributing channel photocurrent by state. Herein, series polymer donors are developed introducing BNIDT block into PM6 backbone. The high electron affinity opposite resonance effect BN bond in results lowered highest occupied molecular orbital (HOMO) largely reduced ΔEST . Moreover, morphology active blends also optimized fine-tuning content. Therefore, recombination via terminal channels traps effectively suppressed. PNB-3 (with 3% BNIDT):L8-BO exhibits both small morphology, favoring more efficient transport. Finally, simultaneously enhanced Voc 0.907 V, Jsc 26.59 mA cm-2 , FF 78.86% contribute champion PCE 19.02%. bonds benchmark polymers possible avenue toward higher-performance OSCs.

Язык: Английский

---

B‒N covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence

National Science Review, Год журнала: 2024, Номер 11(6)

Опубликована: Март 23, 2024

ABSTRACT Multi-boron-embedded multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show promise for achieving both high color-purity emission and exciton utilization efficiency. However, their development is often impeded by a limited synthetic scope excessive molecular weights, which challenge material acquisition organic light-emitting diode (OLED) fabrication vacuum deposition. Herein, we put forward B‒N covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation high-order B/N-based motifs. The structurally electronically extended π-system not only enhances rigidity narrow linewidth but also promotes reverse intersystem crossing mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue (full-width at half-maximum as small 8 nm in n-hexane) have been developed with multi-dimensional improvement photophysical properties compared precursor emitters, enables narrowband OLEDs external quantum efficiencies (EQEmax) up 42.6%, company alleviated decline brightness, representing best reported single-host OLEDs. success these highlights effectiveness our design advanced MR-TADF confirms extensive potential high-performance optoelectronic devices.

Язык: Английский

---

An Efficient Ultra‐Narrowband Yellow Emitter Based on a Double‐Boron‐Embedded Tetraazacyclophane

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Янв. 3, 2025

Abstract Ultra‐narrowband and highly modifiable multiple resonance thermally activated delayed fluorescence (MR‐TADF) materials are crucial for realizing high‐performance wide‐color‐gamut display applications. Despite progress, most MR‐TADF emitters remain confined to blue green wavelengths, with difficulties extending into longer wavelengths without significant spectral broadening, which compromises color purity in full‐color organic light‐emitting diode (OLED) displays. In this work, we present a novel tetraazacyclophane‐based architecture embedding dual boron atoms remarkedly enhance intramolecular charge transfer through the strategic positioning of nitrogen atoms. This arrangement induces substantial redshift while maintaining structural rigidity molecular orbital symmetry, hole‐electron central distance 0 Å, allowing ultra‐narrowband emission. The resulting material, HBN , delivers yellow emission peaking at 572 nm (2.168 eV) an impressively narrow full‐width half‐maximum (FWHM) 17 (0.064 dilute toluene. Moreover, corresponding phosphorescent‐sensitized OLED achieves maximum 581 nm, FWHM 25 high external quantum efficiency 36.1 %, luminance exceeding 40,000 cd m −2 . These outstanding photoluminescent electroluminescent performances validate superiority our design strategy, highlighting its potential cutting‐edge optoelectronic

Язык: Английский

---

Marching Toward Long‐Wavelength Narrowband Emissive Multi‐Resonance Delayed Fluorescence Emitters for Organic Light Emitting Diodes

Advanced Optical Materials, Год журнала: 2023, Номер 11(22)

Опубликована: Окт. 4, 2023

Abstract Over the past decade, thermally activated delayed fluorescence (TADF) emitters have garnered tremendous impetus because of their ability to harvest 100% excitons for light emission in organic emitting diodes (OLEDs). However, despite superior external quantum efficiencies (> 35%), broad spectra with associated full‐width‐at‐half maximum (FWHM > 70 nm) present a limiting factor that must be solved. Recently, multiple‐resonance TADF (MR‐TADF) materials based on heteroatom doped polyaromatic hydrocarbons gained astonishing attention owing remarkable narrowband < 30 nm). majority reported MR‐TADF falls blue/green region, which inevitably jeopardizes application full‐color OLEDs. Therefore, there is an urgent need develop new molecular designs expanding color‐gamut emitters, i.e., λ em 550 nm without compromising emission. To best current knowledge, no detailed reviews focusing different design strategies producing long‐wavelength been date. this end, review highlighting recent advances constructing presented, and photophysics OLED performance discussed. Finally, status future prospects are

Язык: Английский

---

Boron-containing helicenes as new generation of chiral materials: opportunities and challenges of leaving the flatland

Chemical Science, Год журнала: 2024, Номер 15(20), С. 7408 - 7440

Опубликована: Янв. 1, 2024

Recent advances in synthesis have opened the way to a variety of boron helicenes. We highlight main achievements these chiral compounds and discuss their photophysical properties potential as functional materials.

Язык: Английский

---

Stereo effects for efficient synthesis of orange-red multiple resonance emitters centered on a pyridine ring

Chemical Science, Год журнала: 2024, Номер 15(9), С. 3148 - 3154

Опубликована: Янв. 1, 2024

Despite theoretical difficulties, we herein demonstrate an effective strategy for the inaugural synthesis of orange-red multiple resonance (MR) emitter centered on a pyridine ring

Язык: Английский

---

Peripheral Substitution Engineering of MR‐TADF Emitters Embedded With B‒N Covalent Bond Towards Efficient BT.2020 Blue Electroluminescence

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Окт. 15, 2024

Compared with the classical boron/nitrogen (B/N) doped ones, multiple-resonance thermally activated delayed fluorescence (MR-TADF) emitters embedded B-N covalent bond behave a significantly blue-shifted narrowband TADF, and thus show greater potential in ultrapure blue organic light-emitting diodes (OLEDs). As proof of concept, herein peripheral substitution engineering is demonstrated based on such B‒N parent core. The simple approach found to ensure easy synthesis via one-pot lithium-free borylation-annulation, manipulate excited states through different electronic coupling between core substituent, introduce steric hindrance minimize unwanted spectral broadening. Impressively, OLEDs are realized give high external quantum efficiency 20.3% together Commission Internationale de l'Éclairage coordinates (0.152, 0.046). performance well competent those B/N MR-TADF emitters, clearly highlighting that framework novel promising paradigm towards efficient BT.2020 standard.

Язык: Английский

---

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

Advanced Optical Materials, Год журнала: 2025, Номер unknown

Опубликована: Фев. 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.

Язык: Английский

---

Color-tunable circularly polarized electroluminescence from a helical chiral multiple resonance emitter with B-N bonds

Science China Chemistry, Год журнала: 2023, Номер 66(9), С. 2612 - 2620

Опубликована: Авг. 17, 2023

Язык: Английский

---