CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 1
·1452-1460
·
IF 5.2
Shangwei Wang,Ran Pang,Xuexia Chen,Tao Tan,Qi Wang,Chengyu Li,Su Zhang,Taixing Tan,Hongpeng You,Hongjie Zhang
Near-infrared phosphor conversion light-emitting diode (NIR pc-LED) is a widely used ideal NIR light source due to its unique advantages of low cost, energy saving, compactness and long operational lifetime. However, there is currently a scarcity of appropriate phosphor for NIR light sources utilized in spectral detection, with emission peak larger than 850 nm and steady spectrum output of ultra broadband spectra. Here, a broadband Cr 3+ activated LiScSnO 4 (LSS) phosphor ( λ ex-max = 460 nm) matching the pump band of commercial blue LED chips has been developed, which shows a long wavelength NIR emission peaking at 900 nm. Cr 3+ simultaneously replace the Wyckoff site co-occupied by Sc and Sn in LSS. Due to the difference of local environment of the specific crystal field , two different wide emission bands are caused. These two broad emission bands both contribute to the broadband luminescence with a full width at half maximum (FWHM) of 227 nm. Benefiting from the crystallography consistent Wyckoff position occupation of Cr 3+ ions, the spectral distribution of LSS:Cr 3+ exhibit excellent stability over a wide temperature span (80–423 K). The broadband NIR pc-LED prototype based on LSS:Cr 3+ shows great potential in NIR spectrum detection, night vision imaging applications.
研究领域:
材料科学
·
光学工程
·
固态物理
·
光电子学
·
分析化学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2023
·
IF 4.5
Fuhua Gao,Wasim Ullah Khan,Zhiyuan Cheng,Waheed Ullah Khan,Iqtidar Ahmad,Zhiqi Ye,Shenghong Yang,Yueli Zhang
Broadband near-infrared (NIR)-emitting materials have critical applications in biology, medical detection, and NIR night-vision. However, developing NIR phosphors with promising optical properties and excellent thermal stability is a great challenge for research. In this work, a novel NIR phosphor Cr 3+ and Yb 3+ doped CaSc 2 O 4 (CSO) is an evolving NIR emitting phosphor with decent optical properties , boosted emission intensity, and thermal stability that makes it a promising candidate with potential applications in NIR-LED and infrared night-vision. The implications of the fundamental electronic structure of CSO, including valence-band (VB) and conduction-band (CB) orbital character, are investigated. Under blue light excitation, CSO:Cr 3+ is settled with pure broadband NIR emissions (max = 920 nm, FWHM (full width at half maximum) = ∼310 nm) and good thermal stability . The occupation of two selectable lattice sites of Cr 3+ in CSO is discussed in detail. Furthermore, emission enhancements of samples are done by Cr 3+ and Yb 3+ codoping, effectively broadening FWHM to 351 nm and reducing thermal quenching. The energy transfer (ET) routes in CSO:Cr 3+ ,Yb 3+ are investigated based on PL lifetime and comprehensive kinetic ET model, revealing that the PL enhancements by Cr 3+ and Yb 3+ codoping mainly originate from the ET from Cr 3+ to Yb 3+ emitters with more efficient and thermally stable. Finally, an InGaN-LED device encapsulated using CSO:0.01Cr 3+ and CSO:0.01Cr 3+ ,0.01 Yb 3+ phosphor was fabricated. The fabricated NIR pc-LEDs are excellent candidates for NIR light sources in biological imaging and NIR night vision.
研究领域:
光学材料
·
生物医学成像
·
光电子学
·
无机发光材料
·
红外技术
·
固态照明
·
纳米生物技术
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Yu Zhang,Kai Li,Xuelian Zhou,Kaixuan Wang,Ze Wang,Sur Lig,Kefu Chao,Fengqi Zhao
Cr 3+ -doped near-infrared phosphors have recently attracted a wide attention. Here, NIR Ca 1- y Sr y Al 12- x Ga x O 19 :0.12Cr 3+ phosphors are obtained by a high-temperature solid-phase method. First, a series of CaAl 7.88 Ga 4 O 19 :0.12Cr 3+ samples is studied and shows that the crystal field strength can be tuned by cation substitutions, until achieving a sharp emission at 692 nm and a broad emission at 780 nm under a 400 nm excitation, and an internal quantum yield of 90.73%. A further substitution by an appropriate amount of Sr 2+ is suggested to be beneficial to increase the rigidity of the crystal structure by Debye temperature calculations. Experimentally, it is observed that Sr 2+ for Ca 2+ substitutions did not affect the luminescence wavelength and resulted in a significant increase of the thermal stability. When 0.7 Sr 2+ substitute Ca 2+ , the thermal stability at 450 K increased by 28% compared to the samples without Sr 2+ .
研究领域:
材料科学
·
无机化学
·
固体物理
·
光学材料
·
功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Decai Huang,Sisi Liang,Dejian Chen,Jie Hu,Kunyuan Xu,Haomiao Zhu
The emerging applications of near-infrared (NIR) spectroscopy technology in medicine and food security call for compact and efficient NIR light source such as NIR phosphor converted LEDs (pc-LED). Currently, most of the NIR phosphors suffer from low photoluminescence (PL) quantum yield and poor thermal or chemical stability. Herein, a fluoride garnet NIR Na 3 Al 2 Li 3 F 12 :Cr 3+ phosphor was successfully synthesized via coprecipitation method. It can be excited efficiently by blue or red light and shows a broad emission band covering 650–1000 nm (bandwidth of ~110 nm) with a PL quantum yield of 78%. The fine electronic structure of Cr 3+ ions in the host was revealed by the measurement of temperature-dependent (8–300 K) excitation and emission spectra analysis. Particularly, at 423 K, the Na 3 Al 2 Li 3 F 12 :5%Cr 3+ sample retained ~99% of the PL intensity at room temperature, exhibiting excellent PL thermal stability. A NIR pc-LED was fabricated by combining the Na 3 Al 2 Li 3 F 12 :5%Cr 3+ phosphor with a commercial blue LED chip, and radiant flux of 14.3 mW in NIR region was obtained at 60 mA drive current. Furthermore, the penetration of NIR light generated by this pc-LED in chicken breast was reached. The results suggested that Na 3 Al 2 Li 3 F 12 :Cr 3+ is a promising candidate for broadband pc-LED in NIR spectroscopy applications.
研究领域:
材料科学
·
光学工程
·
生物医学光子学
·
半导体器件
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）