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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Energy‐Trapping Management in X‐Ray Storage Phosphors for Flexible 3D Imaging

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(16)

Published: Feb. 18, 2023

X-ray imaging has received sustained attention for healthcare diagnostics and nondestructive inspection. To develop photonic materials with tunable photophysical properties in principle accelerates radiation detection technologies. Here the rational design synthesis of doped halide perovskite CsCdCl3 :Mn2+ , R4+ (R = Ti, Zr, Hf, Sn) are reported as next generation storage phosphors, capability is greatly improved by trap management via Mn2+ site occupation manipulation heterovalent substitution. Specially, Zr4+ displays zero-thermal-quenching (TQ) radioluminescence anti-TQ X-ray-activated persistent luminescence even up to 448 K, further revealing charge-carrier compensation redeployment mechanisms. resolution 12.5 lp mm-1 demonstrated, convenient 3D curved objects realized a time-lapse manner. This work demonstrates efficient modulation energy traps achieve high capacities promote future research into flexible detectors.

Language: Английский

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Ultra‐Sensitive, Selective and Repeatable Fluorescence Sensor for Methanol Based on a Highly Emissive 0D Hybrid Lead‐Free Perovskite

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(35)

Published: June 7, 2022

A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, novel fluorescence probe based on perovskite was successfully designed overcome this bottleneck. We report new zero-dimensional (0D) hybrid of [MP]2 Inx Sb1-x Cl7 ⋅ 6 H2 O (MP=2-methylpiperazine) displaying an unusual green light emission with near-unity photoluminescence quantum yield. Remarkably, 0D exhibits reversible methanol-response luminescence switching between yellow color but fail any other organic vapors. Even blended alcohol solutions, the luminescent excellent sensing performance multiple superiorities response time (30 s) ultra-low limit (40 ppm), etc. Therefore, can be utilized as perfect detect traces from ultrahigh sensitivity, selectivity repeatability. To best our knowledge, work represents first wide potential environmental monitoring detection,

Language: Английский

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Bright Green Emission from Self-Trapped Excitons Triggered by Sb³⁺ Doping in Rb₄CdCl₆

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(12), P. 5717 - 5725

Published: June 10, 2022

Sb3+ with stereochemically active lone pair 5s2 electrons is overwhelming in the doping engineering of luminescent metal halides, and it usually leads to extrinsic self-trapped excitons (STEs) tunable emissions. However, photoluminescence enhancement mechanism doped halides compared pristine host remains unclear. Herein, we into all-inorganic non-emissive Rb4CdCl6, realizing bright green emission peaking at 525 nm a quantum yield 70.2%. A comparison Raman spectra, as well Debye temperature, was utilized elucidate STEs mechanism, verifying that softens structural lattice. Thus, strong electron–phonon interactions enable highly efficient originating from Rb4CdCl6:Sb3+. This work demonstrates solid evidence emissions can be triggered by doping, design principle involved will guide future studies for emerging luminescence material exploration.

Language: Английский

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Dual‐Band‐Tunable White‐Light Emission from Bi³⁺/Te⁴⁺ Emitters in Perovskite‐Derivative Cs₂SnCl₆ Microcrystals

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(9)

Published: Jan. 4, 2022

Luminescent metal halides have attracted considerable attention in next-generation solid-state lighting because of their superior optical properties and easy solution processibility. Herein, we report a new class highly efficient dual-band-tunable white-light emitters based on Bi3+ /Te4+ co-doped perovskite derivative Cs2 SnCl6 microcrystals. Owing to the strong electron-phonon coupling energy transfer from Te4+ , microcrystals exhibited broad dual-band emission originating inter-configurational 3 P0,1 →1 S0 transitions with good stability high photoluminescence (PL) quantum yield up 68.3 %. Specifically, remarkable transition -PL lifetime milliseconds at 10 K microseconds 300 was observed, as solid evidence for isolated emission. These findings provide not only insights into excited-state dynamics but also general approach achieve single-composition lead-free through ns2 -metal ion co-doping.

Language: Английский

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Efficient Near‐Infrared Luminescence in Lanthanide‐Doped Vacancy‐Ordered Double Perovskite Cs₂ZrCl₆ Phosphors via Te⁴⁺ Sensitization

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(26)

Published: April 19, 2022

All-inorganic lead-free perovskite-derivative metal halides have shown great promise in optoelectronics, however, it remains challenging to realize efficient near-infrared (NIR) luminescence these materials. Herein, we report a novel strategy based on Te4+ /Ln3+ (Ln=Er, Nd, and Yb) co-doping achieve NIR vacancy-ordered double perovskite Cs2 ZrCl6 phosphors, which are excitable by low-cost near-ultraviolet light-emitting diode (LED) chip. Through sensitization the spin-orbital allowed 1 S0 →3 P1 transition of , intense multi-wavelength originating from 4f→4f transitions Er3+ Nd3+ Yb3+ was acquired, with quantum yield 6.1 % for emission. These findings provide general approach emission through ns2 -metal lanthanide ion co-doping, thereby opening up new avenue exploring NIR-emitting derivatives towards versatile applications such as NIR-LEDs bioimaging.

Language: Английский

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Regulating the Singlet and Triplet Emission of Sb³⁺ Ions to Achieve Single-Component White-Light Emitter with Record High Color-Rendering Index and Stability

Nano Letters, Journal Year: 2022, Volume and Issue: 22(12), P. 5046 - 5054

Published: May 17, 2022

The rapid development of solid-state lighting technology has attracted much attention for searching efficient and stable luminescent materials, especially the single-component white-light emitter. Here, we adopt a facile ion-doping to synthesize vacancy-ordered double perovskite Cs2ZrCl6:Sb. introduction Sb3+ ions with 5s2 active lone pair into Cs2ZrCl6 host stimulates singlet (blue) triplet (orange) states emission ions, their relative intensity can be tuned through energy transfer from states. Benefiting dual-band as perfect complementary colors, optimum Cs2ZrCl6:1.5%Sb exhibits high-quality white color-rendering index 96. By employing down-conversion phosphor, light-emitting diodes record half-lifetime 2003 h were further fabricated. This study puts forward an effective strategy design emitter, making practical applications them in technologies real possibility.

Language: Английский

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Broadband Emission Origin in Metal Halide Perovskites: Are Self‐Trapped Excitons or Ions?

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(51)

Published: March 29, 2023

Abstract It has always been a goal to realize high efficiency and broadband emission in single‐component materials. The appearance of metal halide perovskites makes it possible. Their soft lattice characteristics significant electron–phonon coupling synergistically generate self‐trapped excitons (STEs), contributing with large Stokes shift. Meanwhile, their structural/compositional diversity provides suitable active sites coordination environments for doping ns 2 ions, allowing 3 P n ( =0,1,2) → 1 S 0 transitions toward emission. ions is phenomenologically similar that STE emission, hindering in‐depth understanding origin, leading failure meet the design requirements practical applications. In this scenario, herein, fundamentals development such two mechanisms are summarized establish clear comprehensive phenomenon, which may pave way an ideal customization broadband‐emission perovskites.

Language: Английский

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Single‐Site Occupancy of Eu²⁺ in Multiple Cations Enables Efficient Ultra‐Broadband Visible to Near‐Infrared Luminescence

Laser & Photonics Review, Journal Year: 2023, Volume and Issue: 17(5)

Published: Jan. 29, 2023

Abstract An important challenge in the research and development of compact near‐infrared (NIR) light sources is discovery new efficient ultra‐broadband NIR luminescent materials to replace conventional Cr 3+ ‐doped compounds. Herein, this work reports a divalent europium‐doped Ba 3 GeO 4 Br 2 phosphor that exhibits high photoluminescence quantum yield 48.8% an ultra‐broad emission band ranging continuously from 500 1100 nm (full width at half maximum = 202 nm) under near‐ultraviolet or blue excitation. A strategy embedding alumina crucible purity graphite devised deployed during solid‐state sintering facilitate conversion Eu into 2+ . Theoretical calculations, structural refinement, spectral analysis demonstrate visible :Eu originates ions occupying distorted Ba3O polyhedra lattice. The as‐prepared phosphor‐converted light‐emitting diode device achieves optical output power 30.1 mW@100 mA (520–1100 photoelectric efficiency 22%@100 (350–1100 nm). Experiments on tissue penetration imaging illustrate its application detection food quality testing appears promising.

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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