Halide Double Perovskite Nanocrystals Doped with Rare‐Earth Ions for Multifunctional Applications

Advanced Science, Journal Year: 2023, Volume and Issue: 10(20)

Published: April 28, 2023

Most lead-free halide double perovskite materials display low photoluminescence quantum yield (PLQY) due to the indirect bandgap or forbidden transition. Doping is an effective strategy tailor optical properties of materials. Herein, efficient blue-emitting Sb3+ -doped Cs2 NaInCl6 nanocrystals (NCs) are selected as host, rare-earth (RE) ions (Sm3+ , Eu3+ Tb3+ and Dy3+ ) incorporated into excellent PLQY 80.1% obtained. Femtosecond transient absorption measurement found that RE not only served activator but also filled deep vacancy defects. Anti-counterfeiting, thermometry, white-light-emitting diodes (WLEDs) exhibited using these ions-doped NCs. For thermometry based on Sm3+ :Sb3+ NCs, maximum relative sensitivity 0.753% K-1 which higher than those most temperature-sensing Moreover, WLED fabricated by NCs@PMMA displays CIE color coordinates (0.30, 0.28), a luminous efficiency 37.5 lm W-1 CCT 8035 K, CRI over 80, indicate NCs promising single-component phosphors for next-generation lighting technologies.

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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Boosting STE and Nd³⁺ NIR Luminescence in Cs₂AgInCl₆ Double Perovskite via Na⁺/Bi³⁺‐Induced Local Structure Engineering

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(50)

Published: Aug. 21, 2023

Abstract Currently, lanthanide (Ln 3+ ) doped Pb‐free double perovskites (DPs) suffer from competitive emissions of the self‐trapped exciton (STE) and Ln . Herein, a new type Nd ‐doped Cs 2 AgInCl 6 DPs with Na + /Bi co‐alloying is developed. Benefiting ‐induced local structural modification, both STE broadband visible luminescence near‐infrared (NIR) are boosted via free sensitization. Specifically, total 648‐fold enhancement in emitting intensities compared to ‐free counterpart realized, significantly improved NIR photoluminescence quantum yield (PLQY) 0.16% 30.3%. First‐principles density functional theory calculations, Raman spectra, steady/transient‐state PL spectra verify modification site symmetry, breakdown parity‐forbidden absorption, reduction electron‐phonon coupling doping. Finally, compact vis–NIR light‐emitting diode (LED) designed by Na/Bi/Nd: DP commercial ultraviolet LED chip, which shows promising applications spectroscopic analyses multifunctional lighting.

Language: Английский

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Broad Dual Emission by Codoping Cr³⁺(d→d) and Bi³⁺(s→p) in Cs₂Ag_0.6Na_0.4InCl₆Double Perovskite

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(33)

Published: June 28, 2023

A phosphor emitting both white light and broad near-infrared (NIR) radiation can simultaneously provide visual inspection early signs of rotting food products. The NIR emission is absorbed by the vibrational overtones water molecules present in items, providing non-invasive image contrast to assess freshness. Here we design a phosphor, namely, Cr3+ -Bi3+ -codoped Cs2 Ag0.6 Na0.4 InCl6 , that emit warm (1000 nm) with quantum yield 27 %. This dual emitter designed combining features s2 -electron (Bi3+ ) d3 (Cr3+ doping weak crystal field halide perovskite host. 6s2→6s16p1${6{s}^{2}\to 6{s}^{1}6{p}^{1}}$ excitation Bi3+ using commercial 370 nm ultraviolet light-emitting-diodes (UV-LED), yields emissions. fraction excited dopants light, other transfers its energy non-radiatively . Then de-excites emission. Temperature dependent (6.4-300 K) photoluminescence combination Tanabe-Sugano diagram show experiences ( Dq/B${{D}_{q}/B}$ =2.2), yielding 4T2→4A2${{{\rm \ }}^{4}{{\rm T}}_{2}\to {{\rm A}}_{2}}$ As proof concept, fabricated panel containing 122 phosphor-converted LEDs, demonstrating capability inspect

Language: Английский

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Broad-Band Sensitization in Cr³⁺–Er³⁺ Co-Doped Cs₂AgInCl₆ Double Perovskites with 1.5 μm Near-Infrared Emission

Chemistry of Materials, Journal Year: 2023, Volume and Issue: 35(14), P. 5291 - 5299

Published: June 30, 2023

Lanthanide (Ln3+)-doped metal halide perovskites with near-infrared (NIR) luminescence have received great attention; however, they suffer from low NIR efficiency, especially for 1.5 μm emission of Er3+ ions. Herein, a Cr3+–Er3+ co-doped Cs2AgInCl6 double perovskite is successfully synthesized using simple solution precipitation method. Besides broad-band 4T2 → 4A2 transition Cr3+ ions centered at 1010 nm, the sample exhibits an NIR-II peak 1540 nm assigned to 4I13/2 4I15/2 can be sensitized by that absorption ultraviolet region (250–900 nm). Excitingly, through assisted post-annealing treatment eliminate defect states, obtains unprecedented high photoluminescence quantum yield (PLQY) 57.5% (Er3+ emission: ∼29.0%), which highest value Ln3+-doped lead-free present. The admirable stability and dual bands pave way light sources pumped multicolor light-emitting diode (LED) chips in potential optical communication, night-vision, infrared imaging applications.

Language: Английский

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Near‐infrared emitting metal halide materials: Luminescence design and applications

InfoMat, Journal Year: 2024, Volume and Issue: 6(5)

Published: March 28, 2024

Abstract Near‐infrared (NIR) luminescent metal halide (LMH) materials have attracted great attention in various optoelectronic applications due to their low‐temperature solution‐processable synthesis, abundant crystallographic/electronic structures, and unique properties. However, some challenges still remain luminescence design, performance improvement, application assignments. This review systematically summarizes the development of NIR LMHs through classifying origins into four major categories: band‐edge emission, self‐trapped exciton (STE) ion defect‐related emission. The mechanisms different types are discussed detail by analyzing typical examples. Reasonable strategies for designing optimizing luminescence/optoelectronic properties summarized, including bandgap engineering, self‐trapping state chemical composition modification, energy transfer, other auxiliary such as improvement synthesis scheme post‐processing. Furthermore, prospects based on devices revealed, phosphor‐converted light‐emitting diodes (LEDs), electroluminescent LEDs, photodetectors, solar cells, x‐ray scintillators, well demonstrations related practical applications. Finally, existing future perspectives LMH critically proposed. aims provide general understanding guidance design high‐performance materials. image

Language: Английский

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Challenges and Strategies to Design Phosphors for Future White Light Emitting Diodes

The Journal of Physical Chemistry C, Journal Year: 2022, Volume and Issue: 126(20), P. 8553 - 8564

Published: May 11, 2022

Phosphor-converted white-light-emitting diodes (pc-WLEDs) are a commercially successful product for energy-efficient illumination. A large number of reported phosphors exhibit high photoluminescence efficiency but struggle in pc-WLED applications. So what kind required to upgrade the existing pc-WLED? An answer this question is provided here. The industry moving toward high-power pc-WLED. For that, issues thermal instability (at ∼200 °C) and luminescence saturation phosphors, along with drop InGaN chip, need be addressed. Another research direction reduce excessive blue light from present commercial pc-WLED, by replacing blue-emitting chip an ultraviolet (UV)-violet chip. Designing UV-violet still remains challenge. This Perspective highlights challenges provides insights address them future.

Language: Английский

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Competing Energy Transfer-Modulated Dual Emission in Mn²⁺-Doped Cs₂NaTbCl₆ Rare-Earth Double Perovskites

The Journal of Physical Chemistry Letters, Journal Year: 2022, Volume and Issue: 13(36), P. 8529 - 8536

Published: Sept. 6, 2022

A2BIBIIIX6 double perovskites are promising materials due to their outstanding photoelectronic properties and excellent stability in the environment. Herein, we synthesized Mn2+:Cs2NaTbCl6 with dual emission through a solvothermal method for first time. exhibit environmental high photoluminescence quantum yields (PLQYs). The Cs2NaTbCl6 was successfully doped Mn2+ two modes: at Mn-feeding concentrations below 1%, tend insert into interstitial void, but if concentration exceeds will further substitute Na+ site of lattice thus both doping modes coexist. After doping, efficient energy transfer from 5D4 level Tb3+ ions 4T1 occurs, resulting tunable Tb3+5D4 → 7FJ=6,5,4,3 transition Mn2+4T1 6A1 transition. Further, LED based on exhibits performance stability. This work demonstrates strategy achieve novel lanthanide-based potential applications photonics.

Language: Английский

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Chemical doping of lead-free metal-halide-perovskite related materials for efficient white-light photoluminescence

Materials Today Physics, Journal Year: 2023, Volume and Issue: 31, P. 100992 - 100992

Published: Feb. 1, 2023

Language: Английский

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Tunable Efficient White Emission in Holmium Doped Double Perovskites Cs₂KInCl₆ via Antimony Sensitization

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(10)

Published: March 12, 2023

Abstract Recently, ns 2 metal ions (such as Bi 3+ and Sb ) doped double perovskites have captured intense attention for their efficient emission, however, achieving tunable white light emission is always an enormous challenge. Herein, /Ho co‐doped Cs KInCl 6 are proposed, the photoluminescence results show that there two bands, one broad cyan band stems from self‐trapped exciton (STE) in [SbCl ] 3‐ octahedron, while another red derives f‐f transitions of Ho . The processes can act sensitizer to activate which due energy transfer channel STE As concentration increases, luminous color be modulated orange under 315 nm irradiation, even obtained with a quantum yield 90 ± 2% when energy‐transfer efficiency 50%. Finally, single compound white‐light emitting diodes fluorescent anti‐counterfeiting labels based on 0.5%Sb /60%Ho fabricated. This work provides effective strategy achieve lead‐free through lanthanide ion co‐doping.

Language: Английский

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