Broadband and Multimode Near‐Infrared Emitter Based on Cr³⁺‐Activated Stannate for Multifunctional Applications

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(7)

Published: Jan. 19, 2023

Abstract Broadband near‐infrared (NIR) phosphors have recently received considerable attention in spectroscopy technology fields, but designing inexpensive, emission peaks centered above 800 nm, and multimodal broadband NIR luminescence material still remains a great challenge. Here, by selecting stannate compound Mg 2 SnO 4 (MSO) as the host, kind of phosphor MSO:Cr 3+ with multimode properties is reported. The designed exhibits an peaking at nm full‐width half maximum 180 (≈2730 cm −1 ). site occupation Cr MSO unraveled density functional theory calculation. constructed light‐emitting device based on displays high output power 187.19 mW@100 mA remarkable photoelectric efficiency 13.67%, its multifunctional applications information encryption, non‐destructive detection, so are also demonstrated. Additionally, through defect reconstruction, presents superior persistent (PersL) PersL duration time longer than 50 h. This work provides feasible strategy to develop intelligent optical integrated low‐cost compounds host toward versatile such detection bioimaging.

Language: Английский

---

Near‐Infrared Light Emitting Metal Halides: Materials, Mechanisms, and Applications

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(21)

Published: Feb. 21, 2024

Near-Infrared (NIR) light emitting metal halides are emerging as a new generation of optical materials owing to their appealing features, which include low-cost synthesis, solution processability, and adjustable properties. NIR-emitting perovskite-based light-emitting diodes (LEDs) have reached an external quantum efficiency (EQE) over 20% device stability 10,000 h. Such results sparked interest in exploring NIR halide emitters. In this review, several different types halides, including lead/tin bromide/iodide perovskites, lanthanide ions doped/based double low dimensional hybrid Bi

Language: Английский

---

Emerging Fe³⁺ Doped Broad NIR‐Emitting Phosphor Ca_2.5Hf_2.5(Ga, Al)₃O₁₂: Fe³⁺ for LWUV Pumped NIR LED

Laser & Photonics Review, Journal Year: 2024, Volume and Issue: 18(5)

Published: Jan. 22, 2024

Abstract Fe 3+ is a promising dopant for designing near‐infrared (NIR) phosphors due to its broadband emitting, non‐toxic, and inexpensive properties. However, the 4 E ( D) + A 1 G) levels of ions are independent crystal‐field parameter, spectral regulation has become huge challenge. Herein, NIR‐emitting phosphor Ca 2.5 Hf (Ga, Al) 3 O 12 : successfully developed toward long‐wave ultraviolet (LWUV) light‐pumped NIR phosphor‐converted LED (pc‐LED). Significantly, excited transition reverse Ga can be realized by simply adjusting concentration, which results in largely enhanced excitation around 410 nm matches well with commercial LWUV LED. Moreover, exhibit emission centered at 770 optimized doping content 0.01 mol%, demonstrated ascribe occupying both octahedral 4+ tetrahedral sites. Further, simple cation modulation strategy proposed break lattice symmetry enhance NIR‐emission intensity 200% as much before. Finally, pc‐LED fabricated employing , Al coating on chip, shows great potential non‐destructive inspection applications.

Language: Английский

---

NIR Mechanoluminescence from Cr³⁺ Activated Y₃Al₅O₁₂ with Intense Zero Phonon line

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(27)

Published: May 1, 2023

Abstract Mechanoluminescence (ML) materials with long‐wavelength emission bands are essential for future in vivo bioimaging, non‐destructive testing of solids, etc. The lack a defined mechanism, however, prevents the application near infrared ML above 650 nm several new fields. Here, addition Ga 3+ ions to Y 3 Al 5 O 12 : Cr manipulates matrix microstructure evolution, boosting near‐infrared (NIR) zero‐phonon line (ZPL) stress optical output ion at 688 nm. key factor changing crystal field intensity D q /B due is what causes luminescence amplification ZPL. fabricated by composite polydimethylsiloxane and 4 GaO (YAGG: ) may penetrate chicken feet epidermal tissue mm pork thanks strong NIR ZPL YAGG: phosphor. This discovery enhancing solid solution provides us technique optimizing materials, as well prospect biological applications.

Language: Английский

---

Unlocking Cr³⁺–Cr³⁺ Coupling in Spinel: Ultrabroadband Near-Infrared Emission beyond 900 nm with High Efficiency and Thermal Stability

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(23), P. 30185 - 30195

Published: May 31, 2024

Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) hold promising potential as next-generation compact, portable, and intelligent NIR light sources. Nonetheless, the lack of high-performance broadband phosphors with an emission peak beyond 900 nm has severely hindered development widespread application pc-LEDs. This study presents a strategy for precise control energy-state coupling in spinel solid solutions composed MgxZn1–xGa2O4 to tune emissions Cr3+ activators. By combining crystal field engineering heavy doping, Cr3+–Cr3+ ion pair from 4T2 state is unlocked, giving rise unusual spanning 650 1400 maximum 913 full width at half-maximum (fwhm) 213 nm. Under optimal Mg/Zn ratio 4:1, sample achieves record-breaking performance, including high internal external quantum efficiency (IQE = 83.9% EQE 35.7%) excellent thermal stability (I423 K/I298 K 75.8%). Encapsulating as-obtained into prototype pc-LEDs yields overwhelming output power 124.2 mW driving current 840 mA photoelectric conversion (PCE) 10.5% 30 mA, rendering performance imaging applications.

Language: Английский

---

Host Dependency of Boundary between Strong and Weak Crystal Field Strength of Cr³⁺ Luminescence

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(9), P. 2319 - 2324

Published: Feb. 22, 2024

Cr3+ doped near-infrared phosphors hold significant applications and generate considerable research interest. The critical parameter for assessing the strength of crystal field in Tanabe–Sugano diagram is boundary value Dq/B, representing ratio splitting to Racah B. Nevertheless, there are conflicting values this parameter, as reported various studies, such 2.1, 2.2, 2.3 C/B = 4.5–4.8. Moreover, some with wide-band emissions exhibit a Dq/B that falls within region contradictory strong field. In study, we numerically determine which distinguishes between weak fields. results then demonstrate dependence on host material correlated parameters B C. This work resolves inconsistency emission profile Cr3+, providing researchers more profound comprehension luminescence.

Language: Английский

---

Developing the Na₂CaZr₂Ge₃O₁₂:Cr³⁺ Garnet Phosphor for Advanced NIR pc-LEDs in Night Vision and Bioimaging

Chemistry of Materials, Journal Year: 2024, Volume and Issue: 36(9), P. 4654 - 4663

Published: May 1, 2024

Materials emitting near-infrared (NIR) light play a crucial role in the development of phosphor-converted light-emitting diodes (pc-LEDs) for applications ranging from fundamental science like spectroscopic analysis to highly applied uses night vision and biological imaging. One class materials that has garnered significant interest these technical spaces is Cr3+-activated garnets due their high efficiency ability operate at relatively temperatures. However, limited emission beyond 800 nm impedes use as optimal blue LED-pumped NIR-emitting materials. In this study, we present new garnet-type NIR phosphor, Na2CaZr2Ge3O12:Cr3+, addresses challenge─the material exhibits long-wavelength (λem,max = 832 nm) good thermal quenching resistance while maintaining an excellent internal quantum (IQE 98%). These properties are attributed crystal environment reconstruction, where structure distortion coupled weak field, which uncommon most rigid phosphors. Furthermore, fabricated pc-LED devices using demonstrate superior performance compared with employing well-known efficient phosphors operating range. The source subsequently demonstrated spanning vision, bioimaging, nondestructive analysis. This study not only provides insights into luminescence garnet desirable but also highlights practical application

Language: Английский

---

Simultaneous NIR Emission and Thermal Stability Enhancement in Garnet‐Type NIR Phosphors through the Synergistic Effect of Lattice Distortion and Enhanced Rigidity

Laser & Photonics Review, Journal Year: 2024, Volume and Issue: 18(10)

Published: May 3, 2024

Abstract Even though there have been significant advancements in the development of Cr 3+ ‐activated near‐infrared (NIR) phosphors, challenge still remains to develop highly efficient and thermally stable NIR phosphors. Here, Ca 4‐x Zn x HfGe 3 O 12 :0.03Cr solid solution phosphors with 834–806 nm emission are constructed by substituting 2+ for , thereby facilitating formation [ZnO 6 ] luminescence site. The coexistence [HfO [Zn/CaO centers is confirmed through DFT calculation, time‐resolved photoluminescence (TRPL) spectroscopy, low‐temperature‐photoluminescence (77 K) spectroscopy. effectively resolves issue lattice mismatch between . Furthermore, simultaneous enhancement intensity thermal stability realized a synergistic combination distortion rigidity enhancement. By optimizing substitution concentration internal quantum efficiency (IQE) 92% an external (EQE) 29% finally achieved. Meanwhile, also enhanced from 59%@400 K (x = 0) 81%@400 0.8). developed phosphor‐converted light‐emitting diodes (pc‐LEDs) exhibit promising prospects fields security, biomedicine, non‐destructive testing rapid identification.

Language: Английский

---

Achieving broadband near-infrared emission with superior anti-thermal quenching by optimizing excited-state population of Cr3+ in Gd3ScGa4O12 garnet phosphors

Materials Horizons, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

A record-breaking anti-thermal quenching of broadband NIR emission (198%@543 K) is achieved in a Cr 3+ -activated garnet phosphor via excited-state population optimization.

Language: Английский

---

High‐Efficiency Short‐Wave Infrared Emitter Enabled by Cr³⁺–Yb³⁺ Co‐Doped Phosphor

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(16)

Published: March 14, 2024

Abstract The utilization of phosphor‐converted light‐emitting diodes (pc‐LEDs) as compact short‐wave infrared (SWIR) emitters has emerged a promising strategy for miniature SWIR spectrometers in portable devices, enabling diverse applications such nondestructive identification, bioimaging, night‐vision surveillance, and optical communication. However, discovering phosphors capable efficiently absorbing blue light emitting pure (>900 nm) remains significant challenge. Here, highly efficient thermally stable luminescence Yb 3+ upon LED excitation by employing Cr –Yb energy transfer Y 3 Ga 5 O 12 garnet is reported. prepared :Cr ,Yb phosphor exhibits intense emission spanning from 900 to 1150 nm at 438 excitation, coupled with ultra‐high internal/external quantum efficiency 80.8%/40.2% excellent thermal stability (108%@150 °C). A pc‐LED prototype fabricated incorporating the optimized commercial 450 chip, shows exceptional performance, delivering output power 92.7 mW driving current 350 mA photoelectric 21.5% 10 mA. This work opens up new avenue designing that exhibit photoluminescence demonstrating potential next‐generation high‐power sources.

Language: Английский

---