ACS Applied Optical Materials
·
2024
·
IF 0
Yonghang Li,Yang Lu,Haonan Ju,Wei Wang,Dong Tu,Hongyu Lu,Jiayu Wang,Hua Zou
Near-infared phosphor-converted light-emitting diodes (NIR pc-LEDs) are next-generation NIR light sources due to their long life, low cost, and compactness. Unfortunately, there is a lack of efficient NIR-II phosphors with high efficiency and large full width at half-maximum (fwhm) that can be excited by violet LED. Here, a series of Cr3+/Ni2+-codoped LiAlSiO4 with unprecedented emission peaking at 1150 nm (∼1000–1400 nm, fwmh ∼191 nm) were synthesized via a solid-state reaction. More importantly, the phosphors exhibit high efficiency and excellent thermal stability under violet emission excitation. Moreover, the NIR pc-LED devices as a NIR-II light source have been fabricated through a combination violet LED and optimized LiAlSiO4:Cr3+/Ni2+ phosphors, which are well applied to high-penetration imaging and nondestructive fruit damage inspection. These results indicate that the LiAlSiO4:Cr3+/Ni2+ phosphors have great potential applications as NIR light sources.
研究领域:
材料科学
·
光学工程
·
电子器件
✓ 已验证
DOI
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Ying Chen,Han Zhang,Yi-Yang Sun
To achieve healthy illumination, phosphor-converted white light-emitting diodes (WLEDs) that can be excited by ultraviolet (UV)-violet light are becoming increasingly important. Herein, we report a novel yellow-emitting phosphor, Ba 2-x Sc 2 B 4 O 11 : x Eu 2+ (BSBO:Eu 2+ ), which exhibits exceptional optical properties and is suitable for UV-violet-excited WLEDs. BSBO:Eu 2+ shows a broad excitation spectrum ranging from 230 to 450 nm, and emits a yellow light with an ultrawide FWHM of about 137 nm centered at 577 nm. The internal and external quantum efficiencies of the phosphor were measured to be 89% and 41%, respectively. The fluorescence lifetime of BSBO:0.01Eu 2+ was determined to be 2.74 μs. By combining BSBO:0.01Eu 2+ with a commercial blue phosphor (BaMgAl 10 O 17 :Eu 2+ ) and a 365 nm LED, we achieved a warm WLED with a correlated color temperature (CCT) of 4543 K. By further integrating a green phosphor ((Ba, Sr) 2 SiO 4 :Eu 2+ ), the WLED achieved superior color quality, reaching an Ra of 93.0, in comparison with the commercial YAG:Ce 3+ with an Ra of 78.4, and a CCT of 7078 K—well-suited for precise color reproduction needs.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 44
·17989-18002
·
IF 3.5
Jie Zhang,Langping Dong,Feng Wang,Jingshan Hou,Yongzheng Fang
Cyan-emitting phosphors are urgently needed to address the “cyan gap” in artificial full-spectrum lighting. In this research, a series of Sr(2−y)BayY4La4(SiO4)6O2:xEu2+ (0.005 ≤ x ≤ 0.08, 0.0 ≤ y ≤ 2.0) phosphors with tunable luminescence was synthesized. Through cation regulation, the luminescence color of Sr(2−y)BayY4La4(SiO4)6O2:xEu2+ can be adjusted from yellow to cyan. Crystal structure analysis revealed that Eu2+ ions simultaneously occupy [Sr1/Ba1Y1La1] and [Sr2/Ba2Y2La2] sites, resulting in multiple luminescence centers and a broadened emission spectrum. With increasing Ba2+ ion concentration, the PLE spectrum was red-shifted from 337 nm to 372 nm, and the excitation intensity in the violet region was significantly enhanced, making it more compatible with violet LED chips. Meanwhile, the PL spectrum was blue-shifted from 543 nm to 496 nm with increasing Ba2+ concentration, accompanied by an increase of about 10 times in the excitation and emission intensity. The optimized Ba2Y4La4(SiO4)6O2:0.02Eu2+ phosphor can be excited by violet light and emits bright cyan light effectively, which can be used to fill the “cyan gap”. Eventually, a series of white LED devices was manufactured by combining the as-prepared luminescence-tunable phosphors with commercial phosphors. Among them, the 410 nm violet LED chip-based WLED(Ba2) device comprising Ba2Y4La4(SiO4)6O2:0.02Eu2+ exhibited the best electroluminescence performance, increasing the color rendering index from 82.0 to 98.6, verifying the compensation effect of the Ba2Y4La4(SiO4)6O2:Eu2+ phosphor on cyan light.
研究领域:
材料科学
·
光电子学
·
固态照明
·
无机化学
·
发光材料
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2025
·Vol. 131
·期 5
·1-10
·
IF 2.8
Ye Huihua,Lin Jinfeng,Wang Xusheng
Three types of CaAl 2 O 4 :Li + phosphors singly doped with Eu 3+ , Sm 3+ , and Ho 3+ ions were synthesized using high temperature solid-state reaction method, and the effects of rare-earth ions and doping concentration on the crystal structure, thermal stability and luminescence properties were systematically studied. The XRD patterns show that all Ca 1 − x Al 2 O 4 :0.01Li + , x Re 3+ (Re = Eu, Sm, Ho) phosphors are pure monoclinic CaAl 2 O 4 phase. And these phosphors can be effectively excited by the characteristic excitation wavelength of the corresponding rare earth ions. Notably, when the doping concentration is less than 15 mol%, the corresponding luminous intensity increases monotonically with the increase of Ho 3+ , while the optimal doping amounts for Eu 3+ and Sm 3+ are 9 mol% and 1 mol%, respectively. Additionally, comparative analysis revealed superior energy transfer efficiency from the matrix to the luminescent center in the CaAl 2 O 4 :0.01Li + , Eu 3+ relative to Sm 3+ and Ho 3+ counterparts. More importantly, the Ca 0.91 Al 2 O 4 :0.01Li + , 0.09Eu 3+ phosphors also exhibit excellent thermal and ageing stability. Its luminous intensity exhibited minimal deviation (< 16%) across an extended temperature range (208 ~ 448 K). Furthermore, after 320 h of thermal aging at 100 °C, the sample retained over 98% of its initial fluorescence intensity. This study provides theoretical and experimental basis for the development of CaAl 2 O 4 -based phosphors for solid-state lighting devices.
研究领域:
材料科学
·
光电子学
·
固态照明
·
无机化学
·
应用物理学
✓ 已验证
产品关联
DOI
高影响因子