Targeted high-precision up-converting thermometer platform over multiple temperature zones with Er³⁺

Materials Horizons, Journal Year: 2023, Volume and Issue: 10(5), P. 1816 - 1824

Published: Jan. 1, 2023

Ratiometric luminescence thermometry based on trivalent erbium ions is a noninvasive remote sensing technique with high spatial and temporal resolution. The thermal coupling between two adjacent energy levels follows the Boltzmann statistics, whose effective range related to gap multi-excited states. However, limitations of different thermally coupled (TCLs) in Er-based thermometers are rarely mentioned. Here, type targeted high-precision thermometer was designed using lead-free double perovskite platform by selecting multiple TCLs Er3+ ion. According selection single system platform, more precise temperature resolution can be obtained regions from 100 K almost 880 K. This work provides quantitative guideline that may pave way for development next generation sensor ions.

Language: Английский

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Pure Green Upconversion from a Multicolor Downshifting Perovskite Crystal

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

Published: March 9, 2023

Abstract Lanthanide‐doped halide perovskite has emerged as a promising phosphor for multimode luminescence. Here, chloride‐based single crystal is reported, namely Cs 2 NaInCl 6 :Yb 3+ ,Er , that grown in hydrothermal reactor. The as‐grown crystals feature two distinct luminescence behaviors under UV and 980 nm laser excitation, respectively. Under lamp the shows multicolor emission of sharp bands at 448, 550, 660 nm, covering wide color gamut CIE diagram. In stark contrast, excitation exhibits pure green upconversion with green‐to‐red ratio up to 211. universal dominance further demonstrated many chlorides, including AgInCl NaBiCl AgBiCl . strong used optical thermometry, which demonstrates an unprecedented sensitivity 9.3% K −1 low temperature end. work introduces kind new hosts single‐band luminescence, opening possibilities areas such low‐threshold pure‐green converter.

Language: Английский

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Red–NIR Luminescence in Rare-Earth and Manganese Ions Codoped Cs₄CdBi₂Cl₁₂ Vacancy-Ordered Quadruple Perovskites

Chemistry of Materials, Journal Year: 2023, Volume and Issue: 35(4), P. 1640 - 1650

Published: Feb. 7, 2023

Combining rare-earth ions (RE3+) in halide perovskites is a hopeful strategy to produce interesting optical properties visible and near-infrared (NIR) regions. Here, RE3+ (RE: Nd, Ho, Er, Tm) are successfully introduced into Cs4Cd1–wMnwBi2Cl12 (0 ≤ w 1) vacancy-ordered quadruple through facile hydrothermal method. In addition the strong orange-red Mn2+ emission, as-prepared materials exhibit effective characteristic emission of red NIR regions via constructing energy bridge. With gradually replacing Cd2+ Cs4Cd1–wMnwBi2Cl12:RE3+, photoluminescence (PL) ranges shows an increasing trend until it reaches strongest value (w = 1). The transfer processes [BiCl6]3– → confirmed, corresponding mechanism explored. According manipulation Mn2+/Cd2+ component, evolution process from direct indirect band gaps verified combined experimental–theoretical approach. White light-emitting diodes (LEDs) fabricated by employing Ho3+-doped Cs4MnBi2Cl12 on near-ultraviolet (n-UV) LED chips, achieving improved color rendering index (CRI) 83.3 93.0 compared that parent compound. Codoping results ultrawide covering both I II regions, implying great potential for detection application.

Language: Английский

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Healthy and High‐Quality Single‐Source Lighting Based on Double‐Doped Tin Halide Engineering

Laser & Photonics Review, Journal Year: 2023, Volume and Issue: 17(9)

Published: April 3, 2023

Abstract Single‐source white light‐emitting diodes (WLEDs) with smart regulation of correlated color temperature (CCT) are indispensable for the next generation WLEDs aimed at healthy and high‐quality illumination, where a suitable CCT value is closely related to our emotions circadian rhythm. Herein, this work constructs single‐component emission layer WLED high performance controllable daily lighting through Bi 3+ /Te 4+ dual‐doped Cs 2 SnCl 6 engineering. The efficient energy transfers between triple self‐trapped exciton states from doping allow two tunable broadband emissions that can cover full‐color region, thereby yielding standout color‐rendering index 94 fabricated WLED. robust stability against heat, ultraviolet light, environmental oxygen/water induces long half‐lifetime up 1104 h. Moreover, strategy endows emitter excitation‐dependent luminescent characteristics, enabling single emissive device realize switching control cold‐, positive‐, warm‐white light by converting excitation chip. Meanwhile, continuous different application scenarios be achieved adjusting current chips. This constitutes solid step toward building single‐source based on lead‐free metal halides.

Language: Английский

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Understanding and Effective Tuning of Red‐to‐Green Upconversion Emission in Ho‐Based Halide Double Perovskite Microcrystals

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 34(4)

Published: Oct. 19, 2023

Abstract Ho‐based lead‐free double perovskite microcrystals (MCs), Cs 2 NaHo 1‐x Yb x Cl 6 , are synthesized and demonstrated to be promising optical temperature sensing materials by understanding the concentration‐dependent upconversion (UC) luminescence mechanisms. By optimizing dopant concentration, a dominant emission shifting from red green is successfully achieved in an activator‐rich system. During this process, intensity ratio (R/G) can changed 12.5 (pure light) 0.14 light). It clarified that cross‐relaxation (CR) process between activator energy transfer 3+ Ho key mechanisms of UC R/G variation. Moreover, shows strong dependence on temperature, resulting competition CR levels. The high‐sensitivity thermometer obtained 0.99 0.01 MCs with bright luminescence, whose fluorescence gains maximum relative sensitivities reaching 0.68% K −1 at 400 K. multicolor quantitative modeling mentioned here crucial for concentration‐dependence characteristics optimize design thermometer. This study extension application range materials.

Language: Английский

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Constructing Efficient and Thermostable Red‐NIR Emitter via Cross Relaxation and Crystal‐Field Engineering of Holmium‐Based Perovskite‐Type Half Metal

Laser & Photonics Review, Journal Year: 2023, Volume and Issue: 18(5)

Published: Dec. 31, 2023

Abstract Lanthanide ions, as dopants, have evoked widespread research interest owing to the rich optical, magnetic, and electrical properties, but their luminescent intensity is always limited by typical concentration quenching. Herein, a holmium‐based double perovskite of Cs 2 NaHoCl 6 reported, which surprisingly breaks through this barrier achieves efficient red‐NIR emission virtue large unit cell, low phonon energy, high content activators, cross relaxation phenomenon between Ho 3+ . The heavy also endows intriguing half‐metallic nature with down‐spin conducting band an up‐spin insulating band. After performing ion doping on crystallographic sites Na + , photoluminescence quantum yield such emitter under 450 nm excitation dramatically promoted 82.3%, benefiting from improved crystal field environment that alleviates parity forbidden rule suppresses non‐radiative recombination loss. Furthermore, heat‐favorable phonon‐assisted population processes enable robust photostability against thermal By combining chip, light‐emitting diodes are fabricated, in wide‐coverage NIR emissions ideally suited for medical light source, night vision, nondestructive examination, transmission imaging. It believed work will open avenue enhancing fluorescence lanthanide ions developing advanced spintronic materials.

Language: Английский

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Recent progress in lanthanide ions doped inorganic metal halide perovskites

Journal of Rare Earths, Journal Year: 2023, Volume and Issue: 42(2), P. 237 - 250

Published: April 10, 2023

Language: Английский

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Achieving Tunable Cold/Warm White-Light Emission in a Single Perovskite Material with Near-Unity Photoluminescence Quantum Yield

Nano-Micro Letters, Journal Year: 2023, Volume and Issue: 15(1)

Published: Aug. 31, 2023

Single materials that exhibit efficient and stable white-light emission are highly desirable for lighting applications. This paper reports a novel zero-dimensional perovskite, Rb4CdCl6:Sn2+, Mn2+, which demonstrates exceptional properties including adjustable correlated color temperature, high rendering index of up to 85, near-unity photoluminescence quantum yield 99%. Using co-doping strategy involving Sn2+ cyan-orange dual-band with complementary spectral ranges is activated by the self-trapped excitons d-d transitions Mn2+ centers in Rb4CdCl6 host, respectively. Intriguingly, although ions doped difficult excite, can be realized through an ultra-high-efficient energy transfer between via formation adjacent exchange-coupled Sn-Mn pairs. Benefiting from this Dexter process, dual shares same optimal excitation wavelengths suppresses non-radiative vibration relaxation significantly. Moreover, relative intensities dual-emission components modulated flexibly adjusting fraction approach short-range represents promising avenue achieving high-quality white light within single material.

Language: Английский

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Thermally Stable Self‐Trapped Assisted Single‐Component White Light from Lead‐Free Zero‐Dimensional Metal Halide Nanocrystals

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(9)

Published: Feb. 25, 2023

Abstract White‐light‐emitting single‐component materials are in high demand for lighting applications. However, achieving white light single‐doped metal halide remains a challenge. Herein, the first time, zero‐dimensional Cs 3 ScCl 6 :Sb 3+ (CSC:Sb ) nanocrystals (NCs) reported that exhibit bright white‐light emission, which is result of combination excessive blue and yellow emissions carbon dots spin‐forbidden electronic transitions Sb ions. CSC:Sb NCs photoluminescence quantum yield 48%. Furthermore, they retain 75% their original efficiency at 100 °C. This thermal stability mainly attributed to its lower dimensionality exciton binding energy as facilitate creation stable elevated temperatures. A white‐light‐emitting diode fabricated using exhibits high‐color rendering index luminous efficacy values 90 23 lm W −1 flux current 200 mA. Therefore, findings may pave way developing next generation devices single component material.

Language: Английский

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Anti‐Solvent Synthesis of Three‐Color Indium‐Based Halide Perovskite Microplate/Microcrystal Phosphors for High Color Rendering WLEDs

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(16)

Published: May 7, 2023

Abstract Lead‐free halide perovskites are emerging as promising eco‐friendly candidates for next‐generation solid‐state lighting because of their nontoxicity and availability broad emission. Herein, a modified room‐temperature anti‐solvent precipitation method is developed to synthesize the Sb 3+ ‐doped, In‐based, lead‐free in microplate/microcrystal structure with different emission colors. The layered InCl 3 serves template growth Cs 2 5 (H O):Sb microplate phosphors. Moreover, presence HCl not only improves solubility precursors, but also provides acid etching effect. resultant ‐doped O) phosphors show bright yellow photoluminescence quantum yield up 92.4%. Furthermore, 6 :Sb NaInCl synthesized through similar method, which displays green deep‐blue emission, respectively. Subsequently, proof‐of‐concept white light‐emitting diodes (WLEDs) fabricated based on + phosphors, achieves high‐quality light color rendering index (CRI) 91.6 95.4, results greatly advance development perovskite synthesis, may offer new possibilities high CRI WLEDs fabrication.

Language: Английский

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