Efficient Broadband Near‐Infrared Emission from Lead‐Free Halide Double Perovskite Single Crystal

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(33)

Published: June 21, 2022

Ultra-broadband near-infrared (NIR) luminescent materials are the most important component of NIR light-emitting devices (LED) and crucial for their performance in sensing applications. A major challenge is to design novel replace traditional Cr3+ -doped systems. We report an all-inorganic bismuth halide perovskite Cs2 AgBiCl6 single crystal that achieves efficient broadband emission by introducing Na ions. Experiments density functional theory (DFT) calculations show originates from self-trapped excitons (STE) emission, which can be enhanced weakening strong coupling between electrons phonons. The high photoluminescence quantum efficiency (PLQY) 51 %, extensive full width at half maximum (FWHM) 270 nm stability provide advantages as a material. single-crystal-based LED demonstrated its potential applications spectral detection well night vision.

Language: Английский

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Reversible Triple-Mode Switching in Photoluminescence from 0D Hybrid Antimony Halides

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(15), P. 6985 - 6995

Published: July 19, 2022

Hybrid metal halides are an emerging class of highly efficient photoluminescent (PL) materials. However, very few them show reversible on–off PL switching under external stimuli and have the potential to perform as next-generation intelligent materials with applications in cutting-edge photoelectric devices. Herein, we report single crystal-to-single crystal (SC–SC) structural transitions among three 0D hybrid antimony halides, namely, nonemissive α-[DHEP]SbCl5 (1), yellow-emissive β-[DHEP]SbCl5·2H2O (2), red-emissive β-[DHEP]SbCl5 (3), by a dynamic phonon-engineering strategy. The SC–SC transformation between 1 2 is triggered acetone or methanol, affording switching. transition solids achieved 3 through process removal/adsorption guest water molecules. Meanwhile, performed introduction which accompanied quenching red emission. Therefore, triple-mode off–onI–onII–off realized halide hybrids for first time, including off–onI (yellow), color-tunable onI–onII (yellow-red), onII–off (red) modes. More importantly, make suitable successful protection anti-counterfeiting confidential information well optical logic gates.

Language: Английский

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Suppressing Auger Recombination of Perovskite Quantum Dots for Efficient Pure-Blue-Light-Emitting Diodes

ACS Energy Letters, Journal Year: 2022, Volume and Issue: 8(1), P. 731 - 739

Published: Dec. 28, 2022

It is a big challenge to achieve pure-blue (≤470 nm) perovskite light-emitting diodes (PeLEDs) with high efficiency and stability. Here, we report (electroluminescence at 469 PeLEDs full width half-maximum of 21 nm, external quantum 10.3%, luminance 12 060 cd m–2, continuous operation half-life 25 h, representing the state-of-the-art performance. This design based on strongly confined CsPbBr3 dots (QDs) suppression Auger recombination, which was enabled by inorganic ligands, replacing initial organic ligands QDs. The ligand acts as "capacitor" alleviate charge accumulation reduce exciton binding energy QDs, suppresses resulting in much lower roll-off PeLEDs. Thus, devices maintain (>10%) (>2000 m–2), considerable significance for display application.

Language: Английский

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2D Perovskite Mn²⁺‐Doped Cs₂CdBr₂Cl₂ Scintillator for Low‐Dose High‐Resolution X‐ray Imaging

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(26)

Published: March 27, 2023

High-performance X-ray scintillators with low detection limits and high light yield are of great importance a challenge for low-dose imaging in medical diagnosis industrial detection. In this work, the synthesis new 2D perovskite, Cs2 CdBr2 Cl2 , via hydrothermal reaction is reported. By doping Mn2+ into yellow emission located at 593 nm obtained, photoluminescence quantum (PLQY) :5%Mn2+ perovskite reaches highest value 98.52%. The near-unity PLQY negligible self-absorption enable excellent scintillation performance 64 950 photons MeV-1 limit 17.82 nGyair s-1 . Moreover, combining poly(dimethylsiloxane) to fabricate flexible scintillator screen achieves resolution 12.3 line pairs (lp) mm-1 results suggest that promising candidate high-resolution imaging. study presents approach designing high-performance through metal-ion doping.

Language: Английский

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Reversible Triple-Mode Photo- and Radioluminescence and Nonlinear Optical Switching in Highly Efficient 0D Hybrid Cuprous Halides

Chemistry of Materials, Journal Year: 2023, Volume and Issue: 35(17), P. 6598 - 6611

Published: Aug. 17, 2023

Multifunctional stimuli-responsive luminescent and optical switching is extremely crucial for wide advanced photonic applications, but it remains a challenging objective halide perovskites. Herein, by performing single-crystal to (SC–SC) transformation as dynamic molecular strategy, we realized reversible triple-mode photoluminescence, radioluminescence (PL RL), nonlinear (NLO) in pair of zero-dimensional (0D) hybrid cuprous halides [ETPP]2Cu4Br6 [ETPP]CuBr2. Specifically, [ETPP]CuBr2 display highly efficient yellow green light emissions under UV excitation with the highest quantum yield up near unity. Simultaneously, identical can also be activated using X-ray RL 57,974 photons MeV–1, surpassing most previously reported halides. Most remarkably, SC–SC between them an ethanol impregnation-heating process, which provides PL/RL transitions two light-emitting states. Additionally, this process accompanied transition centrosymmetric NLO-inactive noncentrosymmetric NLO-active through second harmonic generation (SHG) "silent-active" switching. To best our knowledge, first PL, RL, SHG perovskite chemistry, realize applications data storage, information security, logic gates, etc.

Language: Английский

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Photophysical studies for Cu(i)-based halides: broad excitation bands and highly efficient single-component warm white-light-emitting diodes

Chemical Science, Journal Year: 2023, Volume and Issue: 14(20), P. 5415 - 5424

Published: Jan. 1, 2023

Designing and synthesizing cuprous halide phosphors unifying efficient low-energy emission a broad excitation band is still great challenge. Herein, by rational component design, three novel Cu(i)-based metal halides, DPCu4X6 [DP = (C6H10N2)4(H2PO2)6; X Cl, Br, I], were synthesized reacting p-phenylenediamine with (CuX), they show similar structures, consisting of isolated [Cu4X6]2- units separated organic layers. Photophysical studies uncover that the highly localized excitons rigid environment give rise to yellow-orange photoluminescence in all compounds spanning from 240 450 nm. The bright PL (X Br) originates self-trapped due strong electron-phonon coupling. Intriguingly, DPCu4I6 features dual-band emissive characteristic, attributed synergistic effect halide/metal-to-ligand charge-transfer (X/MLCT) triplet cluster-centered (3CC) excited states. Benefiting broadband excitation, high-performance white-light emitting diode (WLED) high color rendering index 85.1 was achieved using single-component phosphor. This work not only unveils role halogens photophysical processes but also provides new design principles for WLEDs.

Language: Английский

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Carriers, Quasi-particles, and Collective Excitations in Halide Perovskites

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(13), P. 8154 - 8231

Published: June 5, 2023

Halide perovskites (HPs) are potential game-changing materials for a broad spectrum of optoelectronic applications ranging from photovoltaics, light-emitting devices, lasers to radiation detectors, ferroelectrics, thermoelectrics, etc. Underpinning this spectacular expansion is their fascinating photophysics involving complex interplay carrier, lattice, and quasi-particle interactions spanning several temporal orders that give rise remarkable optical electronic properties. Herein, we critically examine distill dynamical behavior, collective interactions, underlying mechanisms in conjunction with the experimental approaches. This review aims provide unified photophysical picture fundamental understanding outstanding light-harvesting properties HPs. The hotbed carrier uncovered HPs underscores critical role ultrafast spectroscopy studies advancing perovskite optoelectronics.

Language: Английский

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Advanced Optical Information Encryption Enabled by Polychromatic and Stimuli‐Responsive Luminescence of Sb‐Doped Double Perovskites

Advanced Science, Journal Year: 2024, Volume and Issue: 11(24)

Published: April 16, 2024

Abstract The smart materials with multi‐color and stimuli‐responsive luminescence are very promising for next generation of optical information encryption anti‐counterfeiting, but these still scarce. Herein, a multi‐level strategy is developed based on the polychromatic emission Sb‐doped double perovskite powders (SDPPs). Cs 2 NaInCl 6 :Sb, KInCl AgInCl :Sb synthesized through coprecipitation methods exhibit broadband emissions bright blue, cyan, orange colors, respectively. transmitted by specific SDPP encrypted when different SDPPs mixed. confidential can be decrypted selecting corresponding narrowband filter. Then, an quick response (QR) code improved security demonstrated this multi‐channel selection strategy. Moreover, three types water‐triggered switching behaviors. represented erased/recovered simple water spray/drying. Whereas, collected from green channel permanently erased moisture, which fundamentally avoids leakage. Therefore, schemes designed to meet variety requirements. multicolor greatly enrich flexibility encryption, leaps level confidentiality.

Language: Английский

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Highly Efficient Light‐Emitting Diodes Based on an Organic Antimony(III) Halide Hybrid

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(6)

Published: Nov. 16, 2021

As low-dimensional lead-free hybrids with higher stability and lower toxicity than those of three-dimensional lead perovskites, organic antimony(III) halides show great application potential in opt-electronic field owing to diverse topologies along exceptional optical properties. We report herein an hybrid (MePPh3 )2 SbCl5 a zero-dimensional (0D) structure, which exhibits brilliant orange emission peaked at 593 nm near-unity photoluminescent quantum yield (99.4 %). The characterization photophysical properties demonstrates that the broadband microsecond lifetime (3.24 μs) arises from self-trapped (STE). Electrically driven light-emitting diodes (OLEDs) based on neat doped films were fabricated. devices significant improvement comparison non-doped OLEDs. Owing much improved surface morphology balanced carrier transport layers devices, peak luminance, current efficiency (CE) external (EQE) are boosted 82 cd m-2 3500 , 1.1 A-1 6.8 0.7 % 3.1 relative respectively.

Language: Английский

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Photophysics in Zero‐Dimensional Potassium‐Doped Cesium Copper Chloride Cs₃Cu₂Cl₅ Nanosheets and Its Application for High‐Performance Flexible X‐Ray Detection

Advanced Optical Materials, Journal Year: 2022, Volume and Issue: 10(6)

Published: Jan. 21, 2022

Abstract Zero‐dimensional Cs 3 Cu 2 Cl 5 exhibits intriguing optical properties, which can meet the basic requirements of ideal scintillator application. Here, green emitter nanosheets are successfully synthesized, and by doping with 2% potassium (K + ), their photoluminescence quantum yield (70.23% to 81.39%), radioluminescence intensity, stability improved. Further experimental theoretical studies point out that: (1) K brings neighboring [Cu ] 3− dimers groups closer, leading lattice shrinkage lower constants; (2) such compact crystal structure results in stronger exciton–photon coupling reduced phonon–electron strength, is beneficial form self‐trapped excitons enhanced luminescence; (3) constants also induce decreased bandgap (2.58 2.51 eV) increased Stokes shift (217 223 nm), for less self‐absorption higher efficiency. Finally, area‐controllable uniform flexible :2%K –polystyrene film achieved excellent X‐ray sensibility. Such shows low cost (2.8223 $/g), broadband response (20–160 keV), high spatial resolution (5 lp mm −1 ) that comparable commercial CsI:Tl wafer. Moreover, it fits well nonplanar surfaces high‐quality medical industrial images applications. It believed this work provide a viable tactic enhance detection metal halide scintillators.

Language: Английский

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