Chiral materials and mechanisms for circularly polarized light-emitting diodes

Nature Photonics, Journal Year: 2024, Volume and Issue: 18(7), P. 658 - 668

Published: March 25, 2024

Language: Английский

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Chiral Hybrid Germanium(II) Halide with Strong Nonlinear Chiroptical Properties

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(41)

Published: Aug. 23, 2023

Due to the pronounced anisotropic response circularly polarized light, chiral hybrid organic-inorganic metal halides have been regarded as promising candidates for application in nonlinear chiroptics, especially second-harmonic generation circular dichroism (SHG-CD) effect. However, designing novel lead-free with large anisotropy factors and high laser-induced damage thresholds (LDT) of SHG-CD remains challenging. Herein, we develop first germanium halide, (R/S-NEA)3 Ge2 I7 ⋅H2 O (R/S-NGI), systematically investigated its linear chiroptical properties. S-NGI R-NGI exhibit (gSHG-CD ) 0.45 0.48, respectively, along a LDT 38.46 GW/cm2 ; these were highest values among reported halides. Moreover, effective second-order optical coefficient could reach up 0.86 pm/V, which was 2.9 times higher than that commercial Y-cut quartz. Our findings facilitate new avenue toward halides, their implementation applications.

Language: Английский

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Room-temperature spin injection across a chiral perovskite/III–V interface

Nature, Journal Year: 2024, Volume and Issue: 631(8020), P. 307 - 312

Published: June 19, 2024

Language: Английский

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Efficient Green Spin Light-Emitting Diodes Enabled by Ultrafast Energy- and Spin-Funneling in Chiral Perovskites

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(20), P. 14157 - 14165

Published: May 10, 2024

Introducing molecular chirality into perovskite crystal structures has enabled the control of carrier spin states, giving rise to circularly polarized luminescence (CPL) in thin films and electroluminescence (CPEL) LEDs. Spin-LEDs can be fabricated either through a spin-filtering layer by chiral-induced selectivity or chiral emissive layer. The former requires high degree polarization compatible spinterface for efficient injection, which might not easily integrated Alternatively, also generate electroluminescence, but efficiency remains low fundamental mechanism is elusive. In this work, we report an green LED based on quasi-two-dimensional (quasi-2D) perovskites as emitting (EML), where CPEL directly produced without separate injection. optimized exhibited strong CPL at 535 nm with photoluminescence quantum yield (PLQY) 91% dissymmetry factor (glum) 8.6 × 10–2. Efficient spin-LEDs were successfully demonstrated, large EL (gEL) 7.8 10–2 maximum external (EQE) 13.5% room temperature. Ultrafast transient absorption (TA) spectroscopic study shows that generated from rapid energy transfer accompanied 2D 3D perovskites. Our only demonstrates reliable approach achieve performance reveals

Language: Английский

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Green Spin Light-Emitting Diodes Enabled by Perovskite Nanocrystals in Situ Modified with Chiral Ligands

ACS Energy Letters, Journal Year: 2025, Volume and Issue: unknown, P. 815 - 821

Published: Jan. 15, 2025

Spin-polarized light-emitting diodes (spin-LEDs) hold promise for next-generation technologies across optical communication, biological imaging, and quantum information processing. Chiral metal halide perovskites, which combine advantageous optoelectronic properties with chirality, are promising materials high-performance spin-LEDs. However, such spin-LEDs still suffer from low efficiency limited brightness, as they often rely on low-dimensional chiral perovskites rather inferior charge-transport spin filter layers. Herein, we demonstrate bright efficient green based perovskite nanocrystals emitters. We employed an in situ ligand modification using R-/S-1-(4-bromophenyl)-ethylammonium bromide to imprint chirality onto CsPbBr3 nanocrystals, exhibited both a high photoluminescence yield of 89% improved relaxation lifetime. A remarkable spin-polarization 88% was observed the nanocrystal films. Consequently, our without commonly used layer simultaneously achieved maximum brightness 12,800 cd m–2, record-high peak external 15.4%, circularly polarized electroluminescence dissymmetry factor 2.16 × 10–3 at room temperature, setting new benchmarks perovskite-based

Language: Английский

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High Comprehensive Circularly Polarized Electroluminescence Performance Improved by Chiral Coassembled Host Materials

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(44)

Published: Aug. 29, 2023

Abstract Circularly polarized organic light‐emitting diodes are of great significance in 3D displays. However, achieving circularly electroluminescence (CP‐EL) simultaneously with a large dissymmetry factor ( g EL ) and high efficiency still remains formidable challenge. Herein, facile efficient strategy is developed for improving the performance CP‐EL devices using device emitting layers chiral coassembled helix nanofiber host materials. Chiral materials (( S ‐/ R ‐2Cz) 0.2 ‐(PFpy) 0.8 could be smartly constructed through intermolecular π–π stacking interactions between achiral conjugated pyridine‐based polymer acceptor (PFpy) binaphthyl‐based donor ‐2Cz). Significantly, resulting hosts greatly promote commercially available phosphorescence emitter to achieve solution‐processed red performances at 620 nm external quantum 4.1% | value 0.014.

Language: Английский

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Core–Shell Perovskite Quantum Dots for Highly Selective Room‐Temperature Spin Light‐Emitting Diodes

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(5)

Published: Nov. 24, 2023

Abstract Circularly polarized light (CPL) is a crucial source with wide variety of potential applications such as magnetic recording, and 3D display. Here, core–shell heterostructured perovskite quantum dots (QDs) for room‐temperature spin‐polarized light‐emitting diodes (spin‐LEDs) are developed. Specifically, 2D chiral shell deposited onto the achiral inorganic (CsPbBr 3 ) core. Owing to chiral‐induced spin selectivity effect, state injected charge carriers biased when they transmitted through shell. The spin‐controlled then radiatively recombine inside CsPbBr emissive core, resulting in CPL emission. It demonstrated that ( R )‐ S )‐1‐(2‐(naphthyl)ethylamine) ‐/ ‐NEA) cations enhance polarization degree due their strong chiroptical properties. Systematical defect analyses confirm (i.e., successfully passivate halide vacancies at surface QDs, thereby attaining high photoluminescence yield 78%. Moreover, spin‐LEDs prepared QDs achieve maximum external efficiency 5.47% circularly electroluminescence P CP‐EL 12% room temperature. Finally, various patterns fabricated by inkjet printing emit CPL, highlighting an emitter next‐generation displays.

Language: Английский

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Efficient Quasi-2D Perovskite Spin Light-Emitting Diodes Based on Chiral-Induced Spin Selectivity

Chemistry of Materials, Journal Year: 2024, Volume and Issue: 36(8), P. 3812 - 3819

Published: April 5, 2024

Perovskites with spin-polarized properties are promising for realizing spin light-emitting diodes (spin-LEDs), yet achieving devices high dissymmetry factors at room temperature remains a significant challenge due to the difficulty in creation of nonequilibrium population. Here, we demonstrate quasi-two-dimensional (2D) perovskite fluorescence and its spin-LED based on chiral-induced selectivity (CISS). By incorporating an achiral organic spacer chiral quasi- 2D film, engineer type II interface within film guarantee effective interphase carrier transfer from low-n quantum well (QW) large exciton binding energy high-n QW. In addition, uniformly vertically distributed QW (n = 1) random orientations is favorable tunneling through spacers hence improved CISS efficiency. Finally, realize |gCP-EL| ∼0.103. Our research reveals that instead solely concentrating limited choice, employing adjust film's landscape, distribution, arrangement more approach achieve emission quasi-2D film.

Language: Английский

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Luminescence regulation of Sb³⁺ in 0D hybrid metal halides by hydrogen bond network for optical anti-counterfeiting

Opto-Electronic Advances, Journal Year: 2024, Volume and Issue: 7(3), P. 230197 - 230197

Published: Jan. 1, 2024

The Sb³⁺ doping strategy has been proven to be an effective way regulate the band gap and improve photophysical properties of organic-inorganic hybrid metal halides (OIHMHs). However, emission ions in OIHMHs is primarily confined low energy region, resulting yellow or red emissions. To date, there are few reports about green Sb³⁺-doped OIHMHs. Here, we present a novel approach for regulating luminescence 0D C₁₀H₂₂N₆InCl₇·H₂O via hydrogen bond network, which water molecules act as agents bonding. shows broadband peaking at 540 nm high photoluminescence quantum yield (PLQY) 80%. It found that intense stems from radiative recombination self-trapped excitons (STEs). Upon removal with heat, C₁₀H₂₂N₆In_1-xSb_xCl₇ generates emission, attributed breaking network large structural distortions excited state. Once adsorbed by C₁₀H₂₂N₆In_1-xSb_xCl₇, it can subsequently emit light. This water-induced reversible switching successfully used optical security information encryption. Our findings expand understanding how local coordination structure influences mechanism provide method control STEs emission.

Language: Английский

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Local symmetry-breaking induces robust circularly polarized luminescence in achiral Dion-Jacobson tin-based perovskites

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 160058 - 160058

Published: Jan. 1, 2025

Language: Английский

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