ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Yu Yan,Mengmeng Shang,Shuai Huang,Yining Wang,Yixin Sun,Peipei Dang,Jun Lin
Near-infrared (NIR) phosphors are fascinating photoluminescence materials with applications in phosphor-converted light-emitting diodes (pc-LEDs) for night vision lighting, which are still restricted by low efficiency and thermal stability in the current research stage. In this work, AScSi2O6 (A = Na/Li) are chosen as hosts due to a larger band gap and a single octahedral site for Cr3+ doping. The NIR-emitting Cr3+-activated AScSi2O6:Cr3+ phosphors were successfully prepared by a common high-temperature solid-state method. X-ray diffraction and Rietveld refinement confirm that the Cr3+ prefers to enter the Sc3+-octahedral lattice site in the AScSi2O6 structure. Under blue light excitation, AScSi2O6:Cr3+ phosphors exhibit broadband NIR emission from 700 to 1100 nm with a full width at half-maximum of ∼150 nm owing to the 4T2 → 4A2 electron transition of Cr3+. The photoluminescence properties were enhanced by adjusting the fluxes and sintering conditions, and highly efficient LiScSi2O6:Cr3+ NIR phosphors with external quantum efficiencies of 33.4% were obtained. Moreover, the optimized LiScSi2O6:Cr3+ exhibits excellent thermal stability (75% at 150 °C) with an activation energy of 0.33 eV. Importantly, the fabricated NIR pc-LED with the highly efficient LiScSi2O6:Cr3+ phosphor demonstrates brighter NIR light and a higher luminous efficacy than the NaScSi2O6:Cr3+ phosphor in night vision.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·Vol. 12
·期 32
·12451-12457
·
IF 5.7
Chaowei Yang,Xikun Zou,Mengqi Lyu,Mingkai Wei,Ziyi Wang,Xiaoyu Shuang,Xuejie Zhang,Bin Dong,Xinming Li,Yan Cong,Mingtao Zheng,Maxim S. Molokeev,Bingfu Lei
Far-red light plays a crucial role in plant growth, development, and flowering as a light signal. However, efficiently obtaining far-red light that well-matches the plant-photosensitive pigment Pfr remains a significant challenge in indoor agriculture. In this study, a far-red phosphor, BaGd2Al2Ga2GeO12:Cr3+(BGAGG:Cr3+), was successfully synthesized, using a high-temperature solid-phase method. Under 450 nm excitation, its emission maximum is at 712 nm with a full width at half maximum (FWHM) of 92 nm, which well-matches with Pfr. Combined with a blue LED chip, this phosphor was used to create a pc-LED device for bok choy and Micro-Tom cultivation experiments. Under the irradiation of far-red light, the biomass of bok choy increased by 39%, and the flowering and fruiting of Micro-Tom was promoted, demonstrating its potential in plant lighting applications.
研究领域:
植物学
·
材料科学
·
农业科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 27
·21290-21296
·
IF 3.84
Fanpeng Cai,Yubin Tang,Fangyan Chen,Yan Yan,Weidong Shi
The removal of tetracyclines (TC), the extensively used antibiotics, from the environment has become an important issue. Recently, photocatalytic oxidation on the surface of semiconductors has been found to provide a good tool for the degradation of TC; however, most of these reactions are UV-light driven rather than visible-light driven. Here, Cr doping of SrTiO3 results in a large decrease in the band gap energy, making Cr3+ doped SrTiO3 (Cr-STO) an attractive material for use as a visible-light-driven photocatalyst for tetracycline (TC) degradation. The photoactivity is improved when the Cr/Sr weight ratio changes from 0.5% to 2%, and decreases when the Cr/Sr weight ratio changes from 3% to 10%. In this paper, we also explain the relationship between the doping and the photocatalytic activity. The existence of ˙OH radicals and holes was studied by the electron spin resonance (ESR) spin-trap technique and trapping experiments.
研究领域:
环境科学
·
材料科学
·
光催化技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Wenbo Ji,Fengmei Zhu,Yuan Gao,Jianbei Qiu
Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs), a widely used NIR light source, are typically prepared by sealing the NIR phosphor powder and an LED chip with epoxy resin. One issue that NIR pc-LEDs frequently encounter is the aging and deterioration of epoxy resin over time, which leads to self-absorption and a sharp decline in emission efficiency. Here, we report the synthesis of a chemically stable NIR luminescent material composed of Cr3+-doped Ba2NaNb5O15 nanocrystals measuring 10–15 nm, with Cr3+ ions located in the octahedral centers of the nanocrystals. Under 460 nm light excitation, the transparent glass-ceramic exhibited a broadband NIR emission in the range of 600–1400 nm, which originated from the electronic transition of Cr3+ from the excited state of 4T2 to the ground state of 4A2. The emission peak was located at ∼810 nm, the FWHM was ∼230 nm, and the internal quantum efficiency reached ∼0.81%. We constructed a stable NIR pc-LED device using optimized transparent NIR-emitting glass-ceramics and a commercially available blue LED chip, demonstrating its promising application in night-vision lighting. Our study provides a basis for the preparation of transparent glass-ceramic-based NIR pc-LED devices as an improved alternative for solid-state illumination.
研究领域:
材料科学
·
光学工程
·
固体照明
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2022
·Vol. 10
·期 24
·9232-9240
·
IF 8.067
Hongzhen Liu,Fangyi Zhao,Hao Cai,Zhen Song,Quanlin Liu
Cr3+-activated near-infrared (NIR) materials are currently attracting extensive attention owing to emerging NIR spectroscopic applications. One promising strategy to tune the excitation and emission spectra is to modulate the compositions and local structure of the host via solid-solutions. However, the intermediate compositions generally have poorer thermal luminescence stability, limiting their practical applications. Herein, we demonstrate that intermediate compositions in pyroxene solid-solutions, (Mg1−yLiy)(Mg1−yScy)Ge2O6:4%Cr3+ (y = 0–1), are better phosphor hosts for Cr3+, possessing higher internal quantum efficiency and thermal luminescence stability. The orthorhombic pyroxene shows more efficient luminescence than the monoclinic one. Ordered occupancy of Li+ and Sc3+ ions in two octahedral sites can optimize bonding and form a more rigid structure, leading to intermediate compositions having enhanced luminescence properties. The composition with y = 0.4 shows a broadband emission centered at ∼874 nm with internal/external quantum efficiencies of 66.6%/31.5%, respectively, and a thermal quenching temperature of up to 410 K. A NIR pc-LED is fabricated to demonstrate its applications in nondestructive detection and night vision imaging. This work provides a strategy for enhancing luminescence through structural optimization.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Optical Materials Express
·
2022
·Vol. 12
·期 3
·981-990
·
IF 3.074
Tao Long,Xiaomeng Yin,Hui Lin,Cheng Zou,Dawei Zhang,Songlin Zhuang
Cr3+ doped Ba0.75Al11O17.25 red luminescent phosphors were synthesized and densified into ceramics by spark plasma sintering. Under the 405 nm excitation, the phosphors present a narrow band emission peaked at 704 nm and the highest emission intensity when the doping concentration of Cr3+ is 3%. When the temperature reaches 205 °C, the integrated emission intensity of the red emission can still reach 88% of the counterpart at room temperature, showing good luminescence thermal stability. The thermal conductivity of the ceramics is 4.87 W/(m·K) at room temperature, which is good for heat release under high power/high brightness excitations.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2021
·
IF 9.811
Jiyou Zhong,Chaojie Li,Weiren Zhao,Shihai You,Jakoah Brgoch
Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) technology has attracted considerable interest as a next-generation light source for emerging NIR spectroscopic applications. However, discovering efficient broadband NIR phosphors necessary to access the desired long-wavelength (λem ≥ 800 nm) energy window remains a challenge. Here, a new phosphate phosphor, KGaP2O7:Cr3+, emerged from a fundamental study of the AMP2O7 (A = Li, Na, K; M = Al, Ga, Sc, In) family. This material combines all of the requisite properties for the efficient generation of NIR photons, including limited defect formation, minimal electron–phonon coupling, a subtle octahedral site distortion, and well-separated transition metal substitution sites. Photoluminescence spectroscopy indicates that this material emits from 700 to 1100 nm (λmax = 815 nm) with a full width at half-maximum (fwhm) of 127 nm or 1874 cm–1. Exciting the material with a blue LED reveals a quantum yield of 74.4% with an absorption efficiency of 44.8%, resulting in an excellent external quantum efficiency as high as 33.3% from the as-prepared sample. A prototype NIR pc-LED device generated an output power of 473.8 mW and a high photoelectric conversion efficiency (10.7% under 500 mA), demonstrating the potential of applying this phosphor in blue LED-based NIR spectroscopy.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2017
·Vol. 85
·期 1
·121-131
·
IF 1.575
Zhang Dong,Guo Qingjie,Ren Yanfang,Wang Changzheng,Shi Qiang,Wang Qinglin,Xiao Xia,Wang Wenjun,Fan Quli
ZnAl 2 O 4 :Cr 3+ crystals were synthesized by using sol–gel method at 1000 °C. The results showed that with the concentration of Cr 3+ in spinel lattices increasing, the x-ray diffraction peaks shifted toward lower diffraction angles, and the grain size revealed a rapid increase and became invariable when the Cr 3+ dopant concentration was above 0.7 mol%. All the samples showed a series of emission peaks ranging from 660 to 730 nm assigned to spin-forbidden 2 E g → 4 A 2g transition of Cr 3+ ions in spinel lattices. The intensity of emission peaks revealed a strong dependence on the Cr 3+ concentration. An additional emission peak at 740 nm was present when the Cr 3+ ions concentration was above 0.5%. All emission peaks were quenched when the Cr 3+ concentration reaches 1.3 mol%. The results of x-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) suggested that the Cr 3+ ions occupied the octahedral sites in spinel lattices, and with the Cr 3+ concentration increasing, the exchange interaction and coupling interaction between Cr–Cr were enhanced and the antisite defects related to Zn in octahedral sites increased. Graphical abstract
研究领域:
材料科学
·
固体物理
·
光学材料
·
无机化学
·
纳米技术
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Min Zhang,Peipei Dang,Yujia Wan,Yingsheng Wang,Zixun Zeng,Dongjie Liu,Qianqian Zhang,Guogang Li,Jun Lin
Visible-to-near-infrared (VIS-NIR) luminescent materials are in great demand in the field of non-destructive testing such as component determination and hyperspectral imaging. Although Cr 3+ -activated phosphors are widely reported, controllable tailoring ultra-wide VIS-NIR luminescence excited by blue light is still a challenge. The strategies of cationic substitution and energy transfers are effective for adjusting the luminescence of Cr 3+ -activated phosphors. In this work, a series of Cr 3+ -doped Sc-based solid solution phosphors (Ba 3-m Sr m Sc 4 O 9 :Cr 3+ ) are reported. Under the excitation of blue light, these phosphors exhibit broadband emission due to the different luminescence centers induced by Cr 3+ occupying different cationic sites. Because of the weaker crystal field strength, Cr 3+ realizes a broadband emission with a longer peak position (λ em = 820 nm) and broader full width at half maximum (FWHM≈182 nm) in Ba 2 SrSc 4 O 9 . Furthermore, Ce 3+ /Yb 3+ ions are introduced into Ba 2 SrSc 4 O 9 :Cr 3+ , achieving an ultra-wide VIS-NIR luminescence (460–1200 nm) by the Ce 3+ →Cr 3+ →Yb 3+ multiple energy transfers. Designing energy transfers is beneficial to improve the quantum efficiency and weaken the thermal quenching. Finally, the NIR phosphor-converted light-emitting diode (pc-LED) fabricated by Ba 2 SrSc 4 O 9 :Cr 3+ demonstrates great potential in night-vision and water component detection. This work provides an effective design idea for controllable tailoring ultra-wide VIS-NIR luminescence by chemical substitution and energy transfer.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yibiao Ma,Weifang Liao,Beibei Quan,Zihui Kong,Maxim S. Molokeev,Andrey Zolotov,Ming Cheng,Xiaoyan Chen,Zhi Zhou,Mao Xia
Lead-free non-rare earth oxide phosphors have attracted wide attention due to their environmental protection, sustainability, and potential to replace halides and fluorides in the field of plant lighting. Among them, the Cr 3+ -excited aluminate phosphor exhibits high brightness, high thermal stability, and far red to near-infrared (NIR) emission due to the influence of the crystal field strength (CFS). This property gives rise to a variety of strategies used to modulate the CFS, for example, single ion substitution, chemical unit co-substitution, etc. Here, we chose the substitution of a single ion, with [BaO6] gradually replacing [SrO6] to form a solid solution. Their structural characteristics and the local structure of Cr 3+ are studied and discussed. The device is packaged to evaluate the feasibility of the material for practical application. The prepared phosphor had a bright far-red light emission of 693 nm under blue light excitation, and this spectrum strongly matched the absorption of plant phytochrome P FR . This work provides the design principle of far red light emission activated by Cr 3+ aluminate solid solution, which can inspire further research on pc-LED lights for plant lighting.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Zhichao Ren,Hongquan Yu,Jinsu Zhang,Xiangping Li,Sai Xu,Baojiu Chen
For the first time, nanotubes of Y3Ga5O12:Cr3+ (referred to as YGO:Cr3+) and Y3Ga5O12:Cr3+/Yb3+ (referred to as YGO:Cr3+/Yb3+) were produced via a single-needle electrospinning method. The nanotubes of YGO:Cr3+ and YGO:Cr3+/Yb3+ have outer diameters between 190 and 210 nm, whereas the inner diameter ranges between 70 and 80 nm, and the wall thickness ranges from 50 to 60 nm. The temperature sensitivity of YGO:0.02Cr3+ nanotubes was examined by studying how the Cr3+ lifetime changes with temperature. In the temperature range of 303 to 723 K, the peak values of Sa and Sr were 0.274 and 0.0067 K–1, respectively. Temperature sensing properties of YGO:0.02Cr3+/yYb3+ (y = 0.01, 0.02, and 0.05) nanotubes were evaluated via the FIR technique utilizing nonthermally coupled energy levels. The I970/I708 in the YGO:0.05Cr3+/0.01Yb3+ nanotubes displayed a maximal Sr value of 0.013 K–1 at 633 K, which exceeds that of other Cr3+-doped NIR phosphors previously reported and is promising for high-temperature measurements.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2020
·Vol. 16
·期 35
·2003121
·
IF 11.459
Yi Zhang,Rui Huang,Hongliang Li,Zhenxu Lin,Dejian Hou,Yanqing Guo,Jie Song,Chao Song,Zewen Lin,Wenxing Zhang,Jing Wang,Paul K. Chu,Chao Zhu
Materials exhibiting persistent luminescence (PersL) have great prospect in optoelectronic and biomedical applications such as optical information storage, bio-imaging, and so on. Unfortunately, PersL materials with multimode emission properties have been rarely reported, although they are expected to be very desirable in multilevel anti-counterfeiting and encryption applications. Herein, Cr 3+ -doped zinc aluminum germanium (ZAG:Cr) nanoparticles exhibiting triple-mode emissions are designed and demonstrated. Upon exposure to steady 254 nm UV light, the ZAG:Cr nanoparticles yield steady bluish-white emission. After turning off the UV light, the emission disappears quickly and the mode switches to transient near-infrared (NIR) PersL emission at predominantly 690 nm. The transient NIR PersL emission which arises from Cr 3+ is induced by non-equivalent substitution of Ge 4+ . After persisting for 50 min, it can be retriggered by 980 nm photons due to the continuous trap depth distribution of ZAG:Cr between 0.65 and 1.07 eV. Inspired by the triple-mode emissions from ZAG:Cr, multifunctional luminescent inks composed of ZAG:Cr nanoparticles are prepared, and high-security labeling and encoding encryption properties are demonstrated. The results indicate that ZAG:Cr nanoparticles have great potential in anti-counterfeiting and encryption applications, and the strategy and concept described here provide insights into the design of advanced anti-counterfeiting materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）