APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 6
·1-10
·
IF 2.5
He Yu,Li Xin,Guo Yangyang,Mao Huibing,Chen Ye,Wang Jiqing
The ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials fabricated by the co-precipitation method have the zinc-blende structure with the crystallite size about 90 ∼ 100 nm. The X-ray diffraction (XRD), the scanning electron microscope (SEM) and the transmission electron microscope (TEM) characterizations confirm that the doping of the Mn 2+ has less effect on the structure of the ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials. With the excitation of a 978 nm laser, the upconversion (UC) emissions of the ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials include two emission bands located at 551 and 664 nm, which correspond to the transitions 5 F 4 ( 5 S 2 )→ 5 I 8 and 5 F 5 → 5 I 8 of the Ho 3+ ions. The UC emission characterization confirms that the UC emission of the ZnS: Ho 3+ , Yb 3+ nanomaterials can be modulated by the doping of the Mn 2+ ions, the increase of the incident laser power and the change of the laser pulse-width. The red emission of the ZnS: Ho 3+ , Yb 3+ nanomaterials particle will increase significantly with the incorporation of the Mn 2+ ions. The incident laser power and the laser pulse-width also can modulate the intensity ratio G / R of the green to the red. With the increase of the incident laser power, the emission intensity ratio G / R will also increase. With the increase of laser pulse-width from 0.2 to 0.8 ms, the above intensity ratio G/R will decrease significantly. The modulation between the green and red emission is due to the energy transfer from the 5 F 4 ( 5 S 2 ) state to the 5 F 5 state of the Ho 3+ ions through the state 4 T 1 of the Mn 2+ ions.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2020
·
IF 4.706
Yuzhen Sun,Huifang Bi,Tao Wang,Leilei Sun,Zexin Li,Haining Song,Fenglei Sun,Haifeng Zhou,Guangjun Zhou,Jifan Hu
NaYF 4 :10Er/0.5Ho/30Ca@NaYF 4 is designed to achieve up-conversion luminescence color adjustment under 980 nm excitation. Ho 3+ doping enhances the red emission level of the system and changes the characteristic green emission into red emission. Importantly, Ho 3+ doping increases the difference in pumping time between green and red excited states. Under short pulse-width laser excitation, the red excited state does not have enough time to be populated, which weakens the emission of red emission, and the ratio of green to red emission will change. It is an effective up-conversion luminescence enhancement method to change the symmetry of crystal field around lanthanide ions by doping Ca 2+ . The green and red emission intensities of NaYF 4 :10Er/0.5Ho/30Ca doped with 30% Ca 2+ ions are 9.0 and 6.3 times higher than those of Ca 2+ free samples, respectively.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Yanbin Wang,Ziqiu Cheng,Junhao Ye,Chen Hu,Zhenzhen Zhou,Yuyang Chen,Haohong Chen,Denis Yu Kosyanov,Jiang Li
Compared to phosphor and phosphor in glass, phosphor ceramics have higher thermal properties , and are less prone to thermal quenching. (Ce,Lu) 3 Al 5 O 12 (Ce:LuAG) has better thermal stability than most of the phosphors, such as (Ce,Y) 3 Al 5 O 12 (Ce:YAG). However, the high melting point of Lu 3 Al 5 O 12 (LuAG; up to 2010 °C) presents a great challenge in producing transparent ceramics (TCs), so a series of Ce:LuAG nanopowders with high sintering activity were prepared by the co-precipitation method and then used as initial materials to obtain x at.% Ce:LuAG ( x = 0.05, 0.1, 0.2, 0.3, 0.35, 0.4, 0.5, 0.55, 0.6, 0.65, 0.7) TCs by vacuum sintering at 1775 °C for 10 h. Moreover, the luminous properties of typical Ce-doped LuAG phosphors were systematically investigated using excitation by light-emitting diodes or laser diodes (LEDs/LDs). The emission intensity of 0.4 at.% Ce doped sample is the highest among all TCs with Ce amount ranging from 0.05 to 0.7 at.% at room temperature. The photoluminescence intensity of 0.4 at.% Ce:LuAG only decreases by 12.5% from 25 to 225 °C. The 0.4 at.% Ce:LuAG based on 0.8 W LEDs and 1.1 W LDs has the optimum luminous flux of 71.5 and 113.7 lm and the luminous efficiency of 89.3 and 101.4 lm∙W −1 , respectively. As Ce concentration increases, a decrease in the luminescence saturation threshold of TCs is observed with a blue laser power density of 2.5–36.9 W∙mm −2 . A high-flux yellow-green light of 1166.9 lm is obtained from 0.1 at.% Ce:LuAG when excited with a high-power LD with an energy density of 36.9 W∙mm −2 . This work explored the best Ce doping level in Ce:LuAG TCs, as well as the luminescence saturation threshold in remote laser lighting applications.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Shanshan Zhao,Dechao Yu,Benchun Li,Saima Kanwal,Tiantian Shen,Jincheng Wu,Songlin Zhuang,Dawei Zhang
The development of blue/green/red tricolor upconversion (UC) phosphors under invisible light irradiation has attracted significant interest in emerging applications such as anti-counterfeiting, three-dimensional (3D) optical data storage, and solid-state 3D displays. In this study, a series of LiYO 2 :RE 3+ ,Yb 3+ (RE = Tm, Ho, Eu) phosphors are successfully prepared via first precipitation process followed by calcination, and completely optimized for efficient tricolor UC luminescence with 980 nm laser excitation. Mechanisms involving two- or three-photon absorption processes and low-phonon-energy-suppressed multi-phonon relaxation have been proposed for Ho 3+ (Eu 3+ )/Yb 3+ and Tm 3+ /Yb 3+ codoping, respectively. In addition, the RE 3+ (Yb 3+ ) concentration-induced phase transition of the LiYO 2 host is discussed for interesting possibilities in spectral regulation. Based on the broad color gamut achieved by the tricolor UC phosphor mixture, homochromatic and polychromatic metamerisms are experimentally fabricated via screen printing for high-level anti-counterfeiting and information security. Moreover, for a proof-of-concept demonstration, prototypes of 3D optical data storage and volumetric displays are constructed by embedding tricolor UC mixtures and their 3D printed patterns in polydimethylsiloxane. It is believed that the continuous exploration of tricolor UC under invisible light excitation for metamerism anti-counterfeiting and 3D displays can promote the development of high-level information security and advanced volumetric display technologies.
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
PHYSICA B-CONDENSED MATTER
·
2024
·
IF 2.8
Yong Tang,Qiuyue Ran
This paper synthesized Y 2 O 3 : Yb 3+ /Er 3+ /Tm 3+ fluorescent crystals (YET) by annealing using the laser zone melting method. When the 365 nm(UV) and 980 nm(IR) lasers are excited together, the luminescence color of YET can be changed by adjusting the laser power. It can be adjusted between orange-red, yellow-green, and white. The temperature sensing characteristics based on the fluorescence intensity ratio (FIR) of non-thermally coupled levels (NTCL) and thermally coupled levels (TCL) of Tm 3+ and Er 3+ ions were studied. The derived maximum relative sensitivity ( S R ) reached the impressive value of 10.871 K -1 (303 K) and 0.511 %K −1 (563K), respectively. Moreover, as the temperature increases, the luminescence of the YET emission changes from white to blue. So, the luminescence emitted by YET can be adjusted between red, green, blue, and white. Therefore, using dual lasers to excite fluorescent materials can provide a suitable method for color-adjustable phosphor.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
EPL
·
2011
·Vol. 96
·期 1
·18001
·
IF 2.753
A. H. Li,Q. Lü
The knowledge of the power density for which luminescence intensity reversal begins with power increase is of valuable importance for practical applications. Under 980 nm CW diode laser excitation, the maximum upconversion luminescence intensities were obtained at 4800, 5700, and 7100 W/cm2 for 2H9/2→4I15/2, 2H11/2&4S3/2→4I15/2, and 4F9/2→4I15/2 transition luminescences, respectively, in compact powder composed by cubic-phase NaYF4:
Yb3+,Er3+ nanoparticles with a most probable diameter of ∼46 nm. It was revealed experimentally that the reversal power density decreases as luminescent level rises. Excitation increase combined with radiative quantum efficiency decrease as power increase can reproduce this "n"-shape power dependence relationship.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
TALANTA
·
2014
·
IF 3.511
Junjie Wang,Yuming Sun,Weijia Zhang,Yong Liu,Xiaoqiang Yu,Ning Zhao
We reported a two-photon ratiometric fluorescent probe for detecting intracellular pH. When excited with 800 nm laser, an optimal output of laser as the routine equipment of two-photon fluorescence microscopy , the two-photon excited fluorescence of this probe showed distinct emission peak shift as large as 109 nm upon the change of pH values in vitro. Very importantly, the experiment results show that this probe has large two-photon absorption cross-section at pH 4.5 at 800 nm of 354 g, which ranks it as one of the best two-photon ratiometric fluorescent pH probes, and its working pH value is between 4.0 and 8.0 which could fit the intracellular pH range. Moreover, utilizing this probe, the two-photon ratiometric fluorescent images in living cells have been obtained, and the spatial coordinates of intracellular pH can be mapped. At the same time, the probe also exhibited selectivity, photostability and membrane permeability. And the photophysical properties of this probe in various solvents indicated that these photophysical properties variations are due to an intramolecular charge transfer process. At last, the imaging depth of the probe in liver biopsy slices was investigated. The experimental results demonstrated the maximum imaging depth can arrive 66 µm in living rat liver tissues.
研究领域:
生物化学
·
细胞生物学
·
医学影像学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2025
·Vol. 27
·期 2
·1-9
·
IF 2.6
Li Guo-Wei,Yan Hang-Yu,Zhang Feng-Yuan,Liu Run-Min,Luoshan Meng-Dai,Zhou Li,Wang Qu-Quan
Highly uniform gold nanorods (GNRs) with tunable surface plasmon resonances (SPRs) across the visible and near-infrared (NIR) spectral regions exhibit attractive photothermal conversion properties along with their chemical stability, good dispersibility, and biocompatibility. In this study, we investigate the optimization of photothermal conversion utilizing GNRs as an agent under the laser excitation at 808 nm, within the NIR-I window. The aspect ratio of GNRs is tuned by the AgNO 3 amount in the reaction solution, and the characteristic longitudinal SPR is of 810 nm at the aspect ratio of 4.43, matching well with the laser wavelength. When the extinction intensity (located around 808 nm) of 810-nm GNR solution is adjusted to 1.0, the photothermal conversion efficiency is achieved to an optimal value of 36.1%, which is approximately 1.7 times that of the sample with the extinction intensity of 0.3. These findings offer insights for the design of effective photothermal conversion agents.
研究领域:
纳米材料学
·
生物医学工程
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Science of Advanced Materials
·
2017
·
IF 1.671
Zhou Zhiping,Yu Yingsen,Sun Quanmin,Liu Xiaotang,Lei Bingfu,Yan Yun
In this work, up-conversion phosphor CaF2:Yb3
+, Er3+ was synthesized by the co-precipitation method. X-ray Diffraction (XRD) and Photoluminescence Spectra (PL) were used to characterize the samples. The effects of annealing temperature and
Yb3+ and Er3+ concentrations on the luminescence properties were discussed. Strong green and red light were obtained under 980 nm laser excitation, the optimal annealing temperature was 600 °C, while the optimal doping concentration was 8 mol% Yb3+ and
0.6 mol% Er3+. The green (540 nm and 552 nm) and red (652 nm and 669 nm) up-conversion luminescence peaks can be ascribed to the transitions of 4S3/2-4I15/2 and 4F9/2-4I15/2, respectively. The
up-conversion luminescence intensities of the green and red emitting peaks can be changed by adjusting the concentration ratio of Yb3+ and Er3+. Hence, it can potentially be used as the red light conversion agent. The dependence of up-conversion intensities (CaF2:Yb3+,
Er3+) on excitation power indicated that two-photon absorption processes were responsible for green and red luminescence.
研究领域:
材料科学
·
光学
·
光子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）