JOURNAL OF RARE EARTHS
·
2018
·
IF 2.524
Tao Pang,Wenbo Peng,Ming Yang,Jianping Xie,Wenhui Lu
An optical heater based on hexagonal NaGdF 4 :Yb 3+ /Er 3+ is reported. XRD , SEM and EDS characterization results show that F − /Ln 3+ can not only control the phase composition , particle size and morphology, but also affect the effective doping concentration of Yb 3+ and Er 3+ . When F − /Ln 3+ is 12/1, the strongest upconversion luminescence is obtained. Based on the luminescent temperature sensing behavior of Er 3+ , the photo-thermal conversion performance was investigated. The results indicate that the temperature of irradiation spot is linearly dependent on the power density, and the photo-thermal responsivity is determined to be 3.3 K·cm 2 /W. Also, it is found that the photo-thermal conversion efficiency can be regulated by changing the Yb 3+ doping concentration. Compared with the nano-gold, copper sulfide and carbon nanotubes , the NaGdF 4 :Yb 3+ /Er 3+ has the triple functions of upconversion luminescence, temperature sensing, and photo-thermal conversion, and may therefore be a promising optical heater for photo-thermal therapy of tumors.
研究领域:
材料科学
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纳米技术
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Rangwei Meng,Zhiyuan He,Xuanhui Luo,Chi Zhang,Mengwei Chen,Halfei Lu,Yingping Yang
In this study, NaGdF 4 :Yb 3+ , Er 3+ @NaGdF 4 :Eu 3+ (NGEY@NGE) core-shell rare earth nanoparticles are prepared by a simple hydrothermal method . After testing, the emission peaks are observed at 415, 525, 540 and 660 nm with an excitation light of 980 nm due to the up-conversion luminescence from rare-earth nanoparticles . Under light excitation at 395 nm, the rare-earth nanoparticles undergo down-conversion luminescence with emission peaks at 590, 610 and 695 nm. The resulting nanoparticles are introduced into the TiO 2 mesoporous layer of hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes to broaden the spectral response of the cells from the visible range to the near-infrared and near-ultraviolet regions, which can guarantee a high light absorption efficiency and corresponding accelerated generation of electron-hole pairs. The results suggest that the mixing of NGEY@NGE nanoparticles into mesoporous TiO 2 layer improves the power conversion efficiency of PSCs to 14.21%, which is 10.6% higher than that of the control cells, which can pave an effective way to improve the performance of PSCs with a broadened response range.
研究领域:
材料科学
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纳米技术
·
太阳能
·
光电
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2015
·
IF 4.772
Yan Song,Guixia Liu,Xiangting Dong,Jinxian Wang,Wensheng Yu,Jingmei Li
Multifunctional nanomaterials possessing upconversion luminescence, magnetic, and photothermal properties show promising applications in biology and medicine. In this study, a new kind of luminescent-magnetic-thermal core–shell hybrid nanocomposite was fabricated combining rare earth Yb3+ and Er3+ ions doped NaGdF4 nanocrystals as shell layer materials and gold nanorods (AuNRs) as cores. The structure, morphology, composition, and properties of the multifunctional hybrid nanocomposites were characterized by X-ray powder diffraction, transmission electron microscopy, energy dispersive spectroscopy, upconversion photoluminescence spectra, vibrating sample magnetometer, sensitive thermometer, and cytotoxicity assessment, respectively. The multifunctional hybrid nanocomposites have rodlike morphology and core–shell structure. The uniform NaGdF4/Yb3+,Er3+ shell with a thickness of around 4.5 nm was coated on the surface of AuNRs with a length of 40 nm and a diameter of 12 nm. The AuNRs@NaGdF4/Yb3+,Er3+ multifunctional nanocomposites provide an excellent upconversion emission under excitation at 980 nm and a superparamagnetic behavior with magnetic susceptibility of 8.0 × 10–5 emu·g–1·Oe–1 at 300 K and saturation magnetization value of 102 emu·g–1 at 2 K. More significantly, when AuNRs@NaGdF4/Yb3+,Er3+ aqueous suspensions of 100 μg·mL–1 were irradiated by a 980 nm NIR laser for 10 min, the temperature was significantly elevated to 48 °C. At the same time, the temperature of photothermal transduction can be easily controlled by adjusting the concentration of nanocomposites. Preliminary investigation of incubating with HeLa cells displays that the multifunctional nanocomposites exhibit a good biocompatibility. Moreover, the nanocomposites may be effectively utilized for bioimaging and photothermal therapy in living cells.
研究领域:
生物医学工程
·
纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 76
·48238-48244
·
IF 3.108
Jiangyun Dai,Chao Yang,Hong Zhang,Hua Zhang,Guoying Feng,Shouhuan Zhou
The successful synthesis of rare earth doped nano/microcrystals with the desired morphology, uniform monodispersity, and intense infrared emission is of fundamental significance, and would facilitate their application in infrared emission-related miniaturization and integration in optoelectronics. However, simultaneously controlling the morphology and enhancing the infrared emission through simple and effective methods has not been well explored. In this study, via Ca2+ doping with an optimized concentration of 25 mol% in the hydrothermal solution, irregular NaGdF4:Yb/Er submicrocrystals converted into highly uniform submicrorods. Meanwhile, an obvious enhancement of visible upconversion (UC) and near-infrared (NIR) downconversion (DC) emission were obtained, probably due to the improved morphology and lowering the local crystal field symmetry around the rare earth ions induced by Ca2+ doping. Furthermore, Ce3+ ions with an optimized concentration of 2 mol% were codoped to intentionally tailor the branching ratio through efficient energy transfer from Er3+ to Ce3+. As a result, the ∼1530 nm emission intensity of the NaGdF4: 25Ca/2Ce/20Yb/2Er submicrorods increased by about 6.4 times in comparison with the NaGdF4:20Yb/2Er counterpart.
研究领域:
材料科学
·
光学工程
·
纳米技术
·
稀土化学
·
光电子学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2020
·
IF 0
Junshan Hu,Ruonan Wang,Rangrang Fan,Fengyi Wang,Huiyu Xiong,Zhenghu Huang,Lixin Liu,Hao Fu
Here, we report a nanocomposite with excellent photothermal performance promising for photothermal treatment. This nanocomposite is prepared by linking Au nanorods (NRs) to NaGdF4:18% Yb3+, 2%Er3+@NaYF4 core–shell upconversion nanoparticles (UCNPs) with bridging of polyethylene glycol molecules. Solutions with the composite nanoparticles can be heated by the irradiation of a near-infrared 980 nm laser, and the photothermal effect in terms of temperature rise can reach 21.3 °C with excitation power density as low as 0.090 W/cm2. This highly effective photothermal performance is attributed to coincidence of the emission band of the UCNPs and the absorption band of the Au NRs, which facilitates the light-to-heat conversion. The structure of the composite and the concentration of the Au NRs in the solution are also optimized through the emission intensity, green-to-red intensity ratio, and the photothermal effect in this work. Compared with previous research studies, the strength in the lower irradiation power density makes the nanocomposite promising for further photothermal treatment and temperature sensing.
研究领域:
生物医学工程
·
纳米技术
·
光学
✓ 已验证
产品关联
DOI
Nanoscale
·
2018
·Vol. 10
·期 40
·19031-19038
·
IF 7.233
Qiuhong Min,Lei Zhao,Yushuang Qi,Jing Lei,Wenbo Chen,Xuhui Xu,Dacheng Zhou,Jianbei Qiu,Xue Yu
An amorphous layer acting as a quenching center at the surface of oleic acid-capped NaGdF4:Yb3+/Tm3+ nanoparticles is observed directly, which can be reconstructed via a novel post-chemical annealing process. The amorphous phase of the surface layer of NaGdF4:Yb3+/Tm3+ nanoparticles gradually crystallizes as the post-chemical annealing temperature increases; meanwhile, the good dispersibility of the as-obtained nanoparticles is maintained. The reduction of surface defects and higher local symmetry of the crystal field environment around the doped rare-earth ions contribute to drastically increased up-conversion (UC) emission intensity of the NaGdF4:Yb3+/Tm3+ nanoparticles. In particular, the blue emission of Tm3+ at 450 nm enhances 10-fold after the post-chemical annealing process at 250 °C compared with the counterpart without further surface-state treatments. The color gamut of well-crystallized NaGdF4:Yb3+/Tm3+ with a modified surface covers the blue to yellow region in CIE chromaticity coordinates via a non-steady-state UC process. The results indicate that the surface states of these UC nanoparticles can be feasibly improved via the post-chemical annealing process without encouraging agglomeration, which further optimizes their UC properties for practical applications.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Guangdong Wu,Juanqin Xue,Zhaoyuan Cao,Yanyan Zhou,Qiang Bi,Yan Zhao,Zhihua Leng
Constructing heterojunction photocatalysts that can make additional utilization of near-infrared (NIR) light has been a global scientific problem and has gained widespread research interest. Upconversion nanoparticles (UCNPs) collaborate with semiconductors to construct UCNPs-based photocatalysts that are used to improve solar energy utilization. In this work, the as-prepared UCNPs-based photocatalysts consisting of NaGdF 4 :Yb 3+ /Er 3+ (NGFYE) and bismuth oxyiodide (BOI) are synthesized by chemical epitaxial growth method and in-situ calcination process. The crystalline phase , morphology, optical and electrochemical properties of NGFYE@BOI samples are investigated in detail. Besides, Bi 4 O 5 I 2 /Bi 5 O 7 I Z-type heterojunction is confirmed by EPR test. Moreover, the photocatalytic elimination of tetracycline hydrochloride (TCH) and its photocatalytic mechanism by NGFYE@BOI samples are explored. This work may provide a promising idea for the efficient and controlled synthesis of UCNPs-based photocatalysts, which will contribute to the future utilization of solar energy.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2019
·
IF 2.687
Huazhen Liao,Song Ye,Yanling Shi,Deping Wang
Small size optical-magnetic bifunctional upconversion nanoparticles (UCNPs) that can be effectively triggered by 808 nm exhibit distinct advantages of improved tissue penetrating depth, minimized overheating effect, possible for multimodal imaging and high clearance rate, which therefore are considered as desirable candidates for bioapplications. In this research, the 808 nm triggered sub-20 nm β-NaYF 4 :Yb 3+ /Er 3+ @NaGdF 4 :Yb 3+ /Nd 3+ @NaGdF 4 active-core@active-shell@inert-shell structured UCNPs with optical and magnetic bifunctional properties were developed by seed-mediated growth method with NaOA as sodium source instead of the generally used NaOH. Through optimizing Nd 3+ doping concentration and outermost NaGdF 4 inert-shell thickness, the optical-magnetic bifunctional core-shell-shell structured UCNPs exhibited strong UC emission intensity and improved magnetic property . Furthermore, the core-shell-shell NPs were validated to be no cytotoxicity by cell viability assessment. Therefore, this research may open a general avenue for the synthesis of small size multifunctional UCNPs for practical bioapplications without overheating.
研究领域:
纳米材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2018
·Vol. 6
·期 19
·5210-5217
·
IF 5.976
Shaohua Fan,Guojun Gao,Zhiquan Lin,Weichang Li,Sijun Fan,Shiyu Sun,Hongtao Sun,Lili Hu
High purity green up-conversion (UC) materials have wide applications in fluorescent labeling, plastic recycling and displays, etc. However, Yb3+/Er3+-based UC materials exhibit poor color purity of green light, and their output color is normally unstable under a variable excitation power density, which hinders their application in the aforementioned areas. Herein, we report the highly stable and efficient pure green UC of rod-like β-NaGdF4:Yb3+,Ho3+ submicro-crystals synthesized via a newly developed ion-exchange modified (IEM) method. IEM-derived NaGdF4:Yb3+,Ho3+ monodisperse submicro-crystals present not only a high-purity green output color (due to the large intensity ratio of green to red, IGreen/IRed ≈ 5) but also excellent color stability under varying conditions, such as excitation power density and doping concentration of Yb3+/Ho3+. More importantly, IEM arouses an enormously enhanced UC emission intensity of ∼3700-fold that of the precursor crystals (PC). The UC emission intensity of IEM β-NaGdF4:Yb3+,Ho3+ is ∼4 times stronger than that of its high temperature annealing (HTA) counterpart. The emission intensity of the single green band is ∼40% stronger than that of the IEM β-NaGdF4:20%Yb3+,2%Er3+ submicro-crystals. A proof-of-concept fluorescent labeling of clover patterns (15 × 12 mm) printed from NaGdF4:Yb3+,Ho3+ ink with stable and high purity green fluorescence is demonstrated under excitation with various power densities.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Pengpeng Lei,Peng Zhang,Shuang Yao,Shuyan Song,Lile Dong,Xia Xu,Xiuling Liu,Kaimin Du,Jing Feng,Hongjie Zhang
Bioimaging probes have been extensive studied for many years, while it is still a challenge to further improve the image quality for precise diagnosis in clinical medicine. Here, monodisperse NaGdF4:Yb3+,Tm3+,x% Bi3+ (abbreviated as GYT-x% Bi3+, x = 0, 5, 10, 15, 20, 25, 30) upconversion nanoparticles (UCNPs) have been prepared through the solvothermal method. The near-infrared upconversion emission intensity of GYT-25% Bi3+ has been enhanced remarkably than that of NaGdF4:Yb3+,Tm3+ (GYT) with a factor of ∼60. Especially, the near-infrared upconversion emission band centered at 802 nm is 150 times stronger than the blue emission band of GYT-25% Bi3+ UCNPs. Such high ratio of NIR/blue UCL intensity could reduce the damage to tissues in the bioimaging process. The possibility of using GYT-25% Bi3+ UCNPs with strong near-infrared upconversion emission for optical imaging in vitro and in vivo was performed. Encouragingly, the UCL imaging penetration depth can be achieved as deep as 20 mm. Importantly, GYT-25% Bi3+ UCNPs exhibit a much higher X-ray computed tomography (CT) contrast efficiency than GYT and iodine-based contrast agent under the same clinical conditions, due to the high X-ray attenuation coefficient of bismuth. Hence, simultaneous remarkable enhancement of NIR emission and X-ray CT signal in upconversion nanoparticles could be achieved by optimizing the doping concentration of Bi3+ ions. Additionally, Gd3+ ions in the UCNPs endow GYT-25% Bi3+ UCNPs with T1-weighted magnetic resonance (MR) imaging capability.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
医学成像
✓ 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）