Highly efficient pure-blue organic light-emitting diodes based on rationally designed heterocyclic phenophosphazinine-containing emitters DOI Creative Commons
Yanping Huo,

Longjiang Xing,

Jianghui Wang

et al.

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 8, 2024

Abstract Multi-resonance thermally activated delayed fluorophores have been actively studied for high-resolution photonic applications due to their exceptional color purity. However, these compounds encounter challenges associated with the inefficient spin-flip process, compromising device performance. Herein, we designed and synthesized two pure-blue emitters based on an organoboron multi-resonance core, incorporating a conformationally flexible donor, 10-phenyl-5H-phenophosphazinine 10-oxide (or sulfide). This design concept selectively modifies orbital type of high-lying excited states charge transfer configuration while simultaneously providing necessary conformational freedom enhance density without sacrificing We show that different embedded phosphorus motifs (phosphine oxide/sulfide) donor can finely tune electronic structure freedom, resulting in accelerated process through intense spin-vibronic coupling, achieving over 27-fold increase reverse intersystem crossing rate compared parent emitter. Utilizing new emitters, achieved high-performance pure blue organic light-emitting diodes, showcasing top-tier external quantum efficiency 37.6% reduced roll-offs. proposed strategy not only conventional notion electron-donors are undesirable constructing narrowband but also offers pathway designing efficient narrow-spectrum diodes.

Language: Английский

Tuning Photophysical Characteristics via Weak Long-Range Charge Transfer in Multi-Resonance Thermally Activated Delayed Fluorescent Molecules DOI

Kaishun Ye,

Chao Shi, Feiyang Li

et al.

Journal of Molecular Structure, Journal Year: 2025, Volume and Issue: unknown, P. 141445 - 141445

Published: Jan. 1, 2025

Language: Английский

Citations

0
High‐Efficiency Solution‐Processed Organic Light‐Emitting Diodes Utilizing Multiple‐Resonance Emitters Incorporating Thiocarbazole Unit DOI Open Access
Shihua Li,

Maoqiu Li,

Yanru Li

et al.

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

Published: Feb. 5, 2025

Abstract Introducing heavy atoms to enhance spin‐orbit coupling represents an effective strategy for boosting the reverse intersystem crossing (RISC) rate constants of Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters. Nevertheless, restricted diversity molecular structures obstructs a thorough investigation structure‐property relationships, thereby limiting improvement device performance, especially in case solution‐processed devices. Herein, alkylthio‐substituted carbazole building block is designed and developed two new MR‐TADF emitters, namely BNCz‐2S BNCz‐4S. Quantum simulations photophysical studies have revealed that as number sulfur increases, BNCz‐4S exhibits higher photoluminescence quantum yield (PLQY), smaller singlet‐triplet energy gap (Δ E ST ) reorganization energy, along with larger (SOC) constant ( k RISC compared BNCz‐2S. Consequently, solution‐processing devices based on exhibit external efficiency (EQE) 24.06%, which first tier reported organic light‐emitting diodes (OLED) date.

Language: Английский

Citations

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

et al.

RSC Advances, Journal Year: 2025, Volume and Issue: 15(10), P. 7383 - 7471

Published: Jan. 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.

Language: Английский

Citations

0
Recent Progress in Molecular Design of Boron/Nitrogen‐Based Multi‐Resonance Materials for Narrowband Organic Light‐Emitting Diodes DOI
Yufang Li, Xiaolan Tan, Bo Cai

et al.

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

Published: April 11, 2025

Abstract Luminescent boron‐nitrogen (BN)‐type multi‐resonance (MR) materials have been first reported by Hatakeyama and co‐workers in 2016. BN‐type MR attracted a lot of attention, because their unique photophysical properties, including narrowband emissions, high photoluminescent quantum yields, thermally activated delayed fluorescent (TADF) properties. MR‐TADF are considered as the next‐generation luminescent for efficient, stable, narrow‐emission organic light‐emitting diodes (OLEDs). Herein, comprehensive review recent progress is provided highlighting structures, device performances. Moreover, future perspective development will be discussed.

Language: Английский

Citations

0
It Matters Where the Heavy Atom Is Placed: Optimizing the Spin–Orbital Coupling in Multiresonant TADF (MR‐TADF) Emitters and Its Impact on OLED Performance DOI Creative Commons
Dongyang Chen, Hui Wang, Feng Huang

et al.

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

Published: April 21, 2025

Abstract This study explores the impact of regioisomerism a heavy chalcogen atom on photophysical properties multi‐resonant thermally activated delayed fluorescence (MR‐TADF) materials. Two pairs isomeric MR‐TADF emitters containing different benzothienocarbazole moieties, tDPABT1B/tDPABT2B and tCzBT1B/tCzBT2B, are synthesized. Theoretical calculations indicate that tDPABT2B tCzBT2B possess higher spin–orbital coupling values (0.27 0.60 cm⁻¹) compared to their respective isomers. The reveals have twofold faster reverse intersystem crossing rate constants 0.5 × 10⁵ 2.7 s⁻¹, respectively, than counterparts. sensitizer‐free organic light‐emitting diodes (OLEDs) with tCzBT1B exhibit green emissions [CIE coordinates (0.12, 0.54)] show high maximum external quantum efficiencies (EQE max ) 34.9 34.3%, respectively. Notably, device demonstrates reduced efficiency roll‐off (34% decrease at 1000 cd cm⁻ 2 (48% ), highlighting distinct benefits importance regiochemistry in contributing an enhancing performance.

Language: Английский

Citations

0
Comprehensive Review on the Structural Diversity and Versatility of Multi-Resonance Fluorescence Emitters: Advance, Challenges, and Prospects toward OLEDs DOI Creative Commons
Xiugang Wu,

Songqian Ni,

Chih‐Hsing Wang

et al.

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: May 9, 2025

Fluorescence emitters with a multiple-resonant (MR) effect have become research hotspot. These MR mainly consist of polycyclic aromatic hydrocarbons boron/nitrogen, nitrogen/carbonyl, and indolocarbazole frameworks. The staggered arrangement the highest occupied molecular orbital lowest unoccupied facilitates MR, resulting in smaller internal reorganization energy narrower emission bandwidth. Optimal charge separation suppresses gap between singlet triplet excited states, favoring thermally activated delayed fluorescence (TADF). MR-TADF materials, due to color purity high efficiency, are excellent candidates for organic light-emitting diodes. Nevertheless, significant challenges remain; particular, limitation imposed by alternated core configuration hinders their diversity versatility. Most existing materials concentrated blue-green range, only few red near-infrared spectra. This review provides timely comprehensive screening from pioneering work present. Our goal is gain understandings structure-performance relationship both basic advanced perspectives. Special emphasis placed on exploring correlations chemical structure, photophysical properties electroluminescent performance depth breadth an aim promote future development emitters.

Language: Английский

Citations

0
Boosting Exciton Utilization Rate in Organic Electroluminescence Devices with BN-Embedded Triangulenes and Triplet Fluorescence Emission DOI

Qian Jin,

Lu Wang,

Lian Duan

et al.

The Journal of Physical Chemistry Letters, Journal Year: 2025, Volume and Issue: unknown, P. 4893 - 4899

Published: May 9, 2025

Organic diradicals with triplet ground states hold the potential to directly harness excitons in electroluminescent devices, thus circumventing slow reverse intersystem crossing process inherent conventional organic fluorescent materials. Despite their significant promise, research into has remained relatively underexplored. [3]Triangulene, a polycyclic aromatic hydrocarbon, possesses state; however, it is nonfluorescent due its alternating symmetry. This study introduces novel strategy break this symmetry by substituting carbon boron or nitrogen, which may enable diradical fluorescence facilitating state transitions. Computational design of BN-integrated [3]triangulene derivatives reveals presence narrowband red and infrared regions, characterized high quantum yields. By strategically positioning substituents at periphery, we further achieve tunable luminescence colors photoluminescence yields that approach 100%. Our highlights promising BN-embedded triangulenes advancement high-performance light-emitting devices.

Language: Английский

Citations

0
Understanding and modulating the horizontal orientations and short‐range charge transfer excited states for high‐performance narrowband emitters DOI Creative Commons

Mingxu Du,

Chen Yang,

Minqiang Mai

et al.

FlexMat., Journal Year: 2024, Volume and Issue: 1(1), P. 46 - 53

Published: April 1, 2024

Abstract Recently, a novel paradigm of boron‐ and nitrogen‐embedded polycyclic nanographites featuring multiple resonance thermally activated delayed fluorescence (MR‐TADF) has garnered substantial interest due to their extraordinary attributes efficient narrowband emissions with small full width at half maxima (FWHMs). Despite an array diverse color tuning strategies, it remains elusive how effectively manipulate device efficiencies without altering the materials' intrinsic MR‐TADF characteristics. Here, advanced ‘non‐conjugate fusion’ design methodology was proposed, aimed dramatically amplifying horizontal orientations emitters while preserving short‐range charge‐transfer properties. As envisioned, when compared classical BCz‐BN mother core, proof‐of‐concept emitter mICz‐BN achieved impressively enhanced dipole ratio ( 83% vs. 75%) analogous emission wavelengths (∼486 nm), FWHMs (∼26 nm) photoluminescence quantum yields (∼93%). Consequently, external efficiency optimized yielded performance enhancement 1.2‐fold 30.5% 25.3%) whilst keeping spectrum almost unchanged.

Language: Английский

Citations

3
Blue multiple resonance emitters exhibiting fast spin flip DOI
Yang Tian, Rongchuan Su, Junjie Liu

et al.

Science China Materials, Journal Year: 2024, Volume and Issue: 67(7), P. 2311 - 2318

Published: May 31, 2024

Language: Английский

Citations

3
High-Performance Deep-Blue Electroluminescence from Multi-resonance TADF Emitters with Spirofluorene-Fused Double Boron Framework DOI Creative Commons
Ke Xu, Nengquan Li, Zeyuan Ye

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Simultaneously extending the π-skeleton and mitigating interchromophore quenching of MR-TADF emitters resulted in narrowband deep-blue electroluminescence with EQE surpassing 40%.

Language: Английский

Citations

2