Laser & Photonics Reviews
·
2023
·
IF 11
Chunli Zhao,Yuan Gao,Jing Wang,Jianbei Qiu
Lead-free rare-earth-based perovskites have received widespread attention for their unique optical properties, although achieving efficient broadband near-infrared (NIR) emission with these materials remains a challenge. Here the synthesis of a rare earth-based double perovskite (Cs 2 NaScCl 6 ) by an improved solid phase method is reported. The doping of Cr 3+ led to the formation of [CrCl 6 ] 3− octahedron, which exhibited a broadband NIR emission peaked at 950 nm and a half-peak width of 162 nm. It is worth noting that with the same actual Cr 3+ content, the luminous intensity of Cs 2 NaScCl 6 synthesized by the improved solid-phase synthesis is four times higher than the product synthesized by the hydrothermal method. an efficient Cl − -Cr 3+ charge transfer sensitization facilitated by localized electrons in [CrCl 6 ] 3− octahedron is the mechanism for the strong NIR emission of Cr 3+ is proposed. Calculations based on density functional theory and Bader charge analysis support the notion that electrons in [CrCl 6 ] 3− octahedrons are strongly localized in Cs 2 NaScCl 6 :Cr 3+ , which is conducive to the Cl − –Cr 3+ charge transfer process, resulting the internal quantum efficiency of 100% and external quantum yield as 42.3%. The highly efficient ultra-broadband NIR emission with excellent stability offers many opportunities for applications in the field of NIR night vision and bio-imaging.
研究领域:
材料科学
·
光学
·
纳米技术
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 44
·16421-16432
·
IF 4
Xiaoyi Liu,Haiming Cheng,Hu Wang,Zhu Wen,Guixia Liu,Shengda Liu,Dan Li,Jinxian Wang,Wensheng Yu,Xiangting Dong
Herein, a new organic cationic matrix [N(CH3)4]3MoO3F3 suitable for Mn4+ doping was constructed. Due to the large steric hindrance of N[CH3]4+ (TMA), charge compensation defects can be effectively prevented in the heterovalent Mn4+-doping process, and a high IQE (91.05%) was obtained. Through the cation co-doping strategy, Mg2+/Zn2+/Li+ cations were introduced into the Mo6+ cationic site, which improved the crystallinity of the matrix and reduced energy losses, so as to improve luminescence intensity, QE, thermal stability, water stability and other spectral properties. Meanwhile, [N(CH3)4]2TiF6:Mn4+ phosphors with the same TMA organic cation and equivalent Mn4+ doping were synthesized for comparison, and the effects of the Mg2+ cation co-doping strategy on the spectral properties of phosphors with different matrix types (fluoride/oxyfluoride) and substitution types (equivalent/non-equivalent) were analyzed. These findings provide the basis for the preparation of new luminescent materials. Furthermore, according to the optical properties exhibited by these phosphors, they are packaged into WLED devices with excellent photoelectric properties, which are suitable for indoor lighting and display fields.
研究领域:
材料科学
·
光学
·
光子学
·
发光材料
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2024
·Vol. 11
·期 20
·7098-7109
·
IF 6.1
Fengmei Zhu,Yuan Gao,Jianbei Qiu
Presently, there is a need to expand the near-infrared (NIR) emission range, especially in the bio-transparent window, to improve the internal quantum efficiency and external quantum efficiency, and to minimize the shortcomings of luminescence properties. In this work, an ultra-broadband NIR emission Cr3+-doped Cs2NaLuCl6 all-inorganic metal halide perovskite phosphor was synthesized by a grinding–sintering method. Under 300 nm excitation, Cs2NaLuCl6:Cr3+ phosphors exhibited ultra-broadband NIR emission of 800–1400 nm, which covers nearly the entire NIR-I (700–1000 nm) and NIR-II (1000–1400 nm) regions; the emission peaked at around 960 nm, with a full width at half maximum of ∼182 nm. Noticeably, the internal- and external-quantum efficiencies of the optimized Cs2NaLuCl6:Cr3+ phosphor were as high as ∼92.9% and ∼60.75%, respectively. We showed through analysis and simulation that the weak crystal field strength is conducive to increasing the odd term of the crystal field, and therefore it partially released the restriction imposed by the parity prohibition law and improved the energy absorption efficiency of Cr3+. As the size of the phosphor approaches the wavelength of NIR luminescence, the apparent Mie scattering effect starts to take effect, which enhances the light extraction of NIR luminescence in the radial direction.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zhongyu Tong,Jiamin Li,Yuqing Yan,Feifeng Huang,Guanyu Zhu,Huanping Wang,Hua Yu,Degang Deng
The development of tunable broadband near-infrared (NIR) fluorescent materials with excellent luminescent properties is still a challenge for the next generation of intelligent NIR light sources. Here, a series of Cr 3+ doped magnetoplum type NIR phosphors were prepared by the high-temperature solid-state method. Their luminescent properties and the methods to broaden the luminescence bandwidth were discussed in detail. In BaAl 12 O 19 : Cr 3+ phosphor, Cr 3+ -Cr 3+ ion pair was constructed based on heavily doped Cr 3+ ions, so as to broaden its spectral emission range. With the increase of Cr 3+ doping concentration, the full width at half maximum (FWHM) of BaAl 12 O 19 : Cr 3+ sample increased from 18.5 nm to 93.7 nm. Furthermore, the crystal field environment of Cr 3+ ions in BaAl 12 O 19 : Cr 3+ phosphors was changed by cationic substitution (Sr 2+ substituted Ba 2+ ion site). The FWHM of NIR emission increases from 49.37 nm to 123.78 nm, and the internal quantum efficiency (IQE) increases from 65.6 % to 76.2 %, with good thermal stability ( I 373 K / I 298 K = 77.3 %). An intense NIR emission of 31.3 mW at 100 mA is produced by the phosphor-converted light-emitting diode (pc-LED), exhibiting a photoelectric efficiency of 15.3 %.
研究领域:
材料科学
·
光学材料
·
固态化学
·
光子学
·
发光光谱学
✓ 已验证
产品关联
DOI
高影响因子