OPTICAL MATERIALS
·
2020
·
IF 2.779
Hua Li,Xiaobo Shi,Xia Li,Lingbo Zong
Size-tunable β-NaYF 4 : Yb/Er (50–400 nm) up-converting nanoparticles (UCNPs) with a strong green emission were successfully prepared by a facile thermal decomposition method in a short period of time. The effects of the reaction time, the oleic acid (OA) content, and the doped Gd 3+ concentration on the crystal structure, the size evolution mechanism and the luminescence mechanism of the β-NaYF 4 : Yb/Er nanoparticles were discussed in detail. Characterization was completed using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution (HR-TEM), scanning electron microscopy (SEM), and photoluminescence (PL). The results reveal that the phase transition was completed at 15 min and the morphology of the NaYF 4 : Yb/Er UCNPs changed from spherical to large hexagonal disks (200–400 nm) in non-doped Gd 3+ . An appropriate decrease in the volume ratio of oleic acid (OA) to 1-octadecene (ODE) promoted NaF production, resulting in the formation of the hexagonal phase crystals and the subsequent increase of luminous intensity by 30–40 times. More importantly, the size of the β-NaYF 4 : Yb/Er decreased with Gd 3+ doping, and the UCNPs ultimately transformed into small hexagonal prisms (50 nm) with high monodispersity when the doping concentration of Gd 3+ was 60 mmoL. The PL spectra confirmed that the luminous intensity of the UCNPs with doped Gd 3+ was much higher than that of the undoped UCNPs. The results show that this route for UCNP fabrication with high luminous efficiency and a small size could be extended to other UCNP systems for multifunctional biomedical applications.
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2016
·
IF 2.435
T. Wei,Y. Shi,Y.F. Xie,Z. Dong,C.Z. Zhao,Q.J. Zhou,C.C. Ding,S. Yuan,F.Y. Xiang,X. Guo,B.Y. Du
Novel tungsten bronze Ba 4 Gd 0.65-x Er 0.02 Yb x Nb 10 O 30 (0 ≤ x ≤ 0.1) phosphors were synthesized. Their phase and structure were characterized and analyzed by X-ray diffraction (XRD) and Rietveld structural refinements. Under 980 nm excitation, bright frequency up-conversion (FUC) green and weak red emissions were observed. The concentration of Yb 3+ had an important influence on the FUC luminescence properties and a possible UC mechanism was proposed. Temperature sensing properties of the Ba 4 Gd 0.55 Er 0.02 Yb 0.1 Nb 10 O 30 phosphor in the range from 303 to 573 K were obtained by measuring the temperature dependent fluorescence intensity ratio (FIR) of the FUC green emissions at 531 and 554 nm originated from two thermally coupled 2 H 11/2 and 4 S 3/2 emitting energy levels. A temperature-sensing sensitivity of 0.013 K −1 at 573 K was obtained experimentally and the obtained energy difference ΔE was 971 cm −1 , indicating that this material can be utilized as a promising candidate for the future optical temperature sensors of high accuracy and resolution.
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 ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Qiqi Nie,Yongbo Wang,Licong Jia,Bei Liu,Enzhou Liu,Xiaoyun Hu,Jun Fan
In this paper, a novel detection method based on luminescence resonance energy transfer (LRET) system for sensitive detection of Mn 2+ ions has been proposed. The positively charged upconversion nanoparticles capped with polyethyleneimin (PEI-UCNPs) and negatively charged Ag NPs capped with tripolyphosphate (P 3 O 10 5− -Ag NPs) were bound through electrostatic interaction . They were used as energy donors and acceptors, respectively. The green upconversion luminescence could be quenched because of a good overlap between the UCNPs emission and the Ag NPs absorption spectra . Nevertheless, the LRET was disrupted and the green upconversion luminescence was restored in the presence of Mn 2+ because of the coagulation of P 3 O 10 5− -Ag NPs. Thus, the relative luminescence intensity increased as the concentrations of Mn 2+ increased. The response is linear to the concentrations of Mn 2+ in the range from 0.2 to 5 μM, and the detection limit is evaluated to be 150 nM (S/N = 3). This probe was easy to operate with satisfactory selectivity and excellent sensitivity, which would be able to satisfy the requirements of Mn 2+ -related detection.
研究领域:
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2016
·Vol. 8
·期 45
·19014-19024
·
IF 7.76
Lijie Bai,Wenya Jiang,Chunxiao Gao,Shuxian Zhong,Leihong Zhao,Zhengquan Li,Song Bai
The combination of upconversion nanocrystals with a wide-bandgap semiconductor is an efficient strategy to develop near-infrared (NIR)-responsive photocatalysts. The photocatalytic activity of the hybrid structures is greatly determined by the efficiency of the energy transfer on the interface between upconversion nanocrystals and the semiconductor. In this work, we demonstrate the interface design of a NaYF4:Yb,Tm–BiOCl hybrid structure based on the choice of suitable BiOCl facets in depositing NaYF4:Yb,Tm upconversion nanocrystals. It was found that the selective deposition of NaYF4:Yb,Tm nanocrystals on the BiOCl(110) facet can greatly enhance the photocatalytic performance in dye degradation compared with the sample with NaYF4:Yb,Tm nanocrystals loaded on the BiOCl(001) facet. Two effects were believed to contribute to this enhancement: (1) a stronger UV emission absorption ability of the BiOCl(110) facet from NaYF4:Yb,Tm in generating more photo-induced charge carriers resulted from the narrower bandgap; (2) a shorter diffusion distance of photogenerated charge carriers to the BiOCl(110) reactive facet for surface catalytic reactions owing to the spatial charge separation between different facets. This work highlights the rational interfacial design of an upconversion nanocrystal–semiconductor hybrid structure for enhanced energy transfer in photocatalysis.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 31
·19205-19210
·
IF 3.108
Jing Yan,Honghu Yao,Junhao Li,Shiman He,Qili Wu,Xianfeng Yang,Wasim Ullah Khan,Jianxin Shi,Mingmei Wu
To meet the increasing requirement, much effort has been devoted to enhance the emission intensity and tailor the emission color of rare earth phosphors. However, limited contributions have been made to the up-conversion (UC) of nanorods by complete epitaxial growth on each facet to achieve this requirement. In this study, we propose a facile epitaxial growth route to grow anisotropic hexagonal β-NaYF4:Yb3+/Ho3+@β-NaYbF4:Er3+, β-NaYF4:Yb3+/Ho3+@β-NaYF4, and β-NaYbF4:Er3+@β-NaYF4 core/shell nanorods, which were realized by adding hexagonal β-NaYF4:Yb3+/Ho3+ or β-NaYbF4:Er3+ nanorods as a core-nanostructure into a solution containing cubic α-NaYbF4:Er3+ or α-NaYF4 nanoparticles as the shell-precursor. During epitaxial growth-induced phase transformation, the precursor nanoparticles disappeared gradually in the solution and consequently corresponding β-phased shell yielded on each outer facet of each β-phased nanorod core. Eventually, the nanorod core was covered completely with a uniformly grown β-NaYbF4:Er3+ or β-NaYF4 shell. The UC emission of either β-NaYF4:Yb3+/Ho3+ or β-NaYbF4:Er3+ core can be enhanced by the outer shell due to the decrease in the number of surface defects. In addition, tailored UC emissions could be obtained by controlling the shell components and thickness, typically in the core/shell nanorods of β-NaYF4:Yb3+/Ho3+@β-NaYbF4:Er3+. The tunable colors with improved emission in these core/shell nanorods may find wider applications in multicolor labeling and anti-counterfeiting.
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 MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Yu-Li Dang,Li-Xia Xie,Na-Na Fei,Ru Qiao,Zhan-Qi Cao,Li-Jie Liu,Guo-Xing Liu,Xin Zheng,Yun-Lai Ren,Xia Sheng,Sheng-Qiang Guo,Cao-Yuan Niu
Two porphyrin ligands with peripheral chelate groups linked at meso and β positions and their two new non-sandwich-type ytterbium(III)-porphyrin coordination compounds have been synthesized. New porphyrin compounds and the two coordination compounds were characterized by Nuclear Magnetic Resonance, High Resolution Mass Spectrum, Ultraviolet and visible, and fluorescence in the visible and Near Infrared (NIR) regions. The two Yb(III) complexes afforded the photoluminescence quantum yields of 2.0% and 1.6% for Yb(III) characteristic NIR emission in DMSO. Finally and importantly, the impact factors on the sensitization of Yb(III) NIR emission by porphyrin ligands via non-sandwich-type linkage were investigated by theoretical calculations and further measurements on fluorescent properties. It is proposed that the sensitization efficiency for the distance between the sensitizer and Yb(III) NIR emitter is better than that for conjugated degree of the peripheral porphyrin linkage.
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 15
·6743-6756
·
IF 4.5
Zhou Huan,Wang Jie,Yang Bing,Sun Manna,Liang Chunyong,Yang Lei,Zhao Xiaoyan,Wang Hongshui
In this work, near-infrared light responsive upconversion nanoparticles TiO 2 /(Ca,Y)F 2 :Tm,Yb were hydrothermally prepared for tumor control. Moreover, femtosecond laser was adopted to reduce particle size and aggregation of TiO 2 /(Ca,Y)F 2 :Tm,Yb, as a strategy to enhance its dispersity. In vitro studies of the biocompatibility and tumor control efficacy of TiO 2 /(Ca,Y)F 2 :Tm,Yb were carried out via co-culturing human pancreatic carcinoma cells (CFPAC-1). It was found in the absence of near-infrared light, TiO 2 /(Ca,Y)F 2 :Tm,Yb showed no toxicity to CFPAC-1 cells. On contrast, when exposed to near-infrared light, particles exhibited irradiation time, irradiation interval and particle concentration dependent suppression of CFPAC-1 cells proliferation along with portion of S phase cells increase. A nude mouse model with CFPAC-1 cells injection was established and TiO 2 /(Ca,Y)F 2 :Tm,Yb was subsequently applied for in vivo tumor control. A 15 days tracking confirmed the antitumor capability of near-infrared light excited TiO 2 /(Ca,Y)F 2 :Tm,Yb. Overall, we anticipate that the here-introduced TiO 2 /(Ca,Y)F 2 :Tm,Yb can serve as an effective agent for photodynamic antitumor therapy. Graphical Abstract
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2022
·Vol. 12
·期 11
·1608
·
IF 2.67
Zijun Ye,Yu Jiang,Minmin Mao,Zhiyu Xiu,Mengjiao Chi,Guofa Wu,Bing Liu,Dawei Wang,Bin Yang,Kaixin Song
In this work, Y2.95R0.05MgAl3SiO12(R = Yb, Y, Dy, Eu, Sm) microwave single-phase dielectric ceramics were successfully prepared via a conventional ceramic sintering technology by doping a series of rare earth elements (Yb, Y, Dy, Eu, Sm) with different ionic radii for the first time. The effects of A-sites occupied by rare earth elements on the microwave dielectric properties of Y2.95R0.05MgAl3SiO12were studied using crystal structure refinement, a scanning electron microscope (SEM), bond valence theory, P-V-L theory, and infrared reflection spectroscopy. It was found that the ionicity of the Y-O bond, the lattice energy, the bond energy, and the bond valance of the Al(Tet)-O bond had important effects on the microwave dielectric properties. Particularly, the optimum microwave dielectric properties,εr= 9.68,Q×f= 68,866 GHz, andτf= −35.8 ppm/°C, were obtained for Y2.95Dy0.05MgAl3SiO12when sintered at 1575 °C for 6 h, displaying its potential for 5G communication.Keywords:garnet;microwave dielectric properties;P–V–L theory;infrared reflection spectroscopy
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-11
·
IF 17.694
Liao Jinsheng,Wang Minghua,Lin Fulin,Han Zhuo,Fu Biao,Tu Datao,Chen Xueyuan,Qiu Bao,Wen He-Rui
Rare earth (RE 3+ )-doped phosphors generally suffer from thermal quenching, in which their photoluminescence (PL) intensities decrease at high temperatures. Herein, we report a class of unique two-dimensional negative-thermal-expansion phosphor of Sc 2 (MoO 4 ) 3 :Yb/Er. By virtue of the reduced distances between sensitizers and emitters as well as confined energy migration with increasing the temperature, a 45-fold enhancement of green upconversion (UC) luminescence and a 450-fold enhancement of near-infrared downshifting (DS) luminescence of Er 3+ are achieved upon raising the temperature from 298 to 773 K. The thermally boosted UC and DS luminescence mechanism is systematically investigated through in situ temperature-dependent Raman spectroscopy, synchrotron X-ray diffraction and PL dynamics. Moreover, the luminescence lifetime of 4 I 13/2 of Er 3+ in Sc 2 (MoO 4 ) 3 :Yb/Er displays a strong temperature dependence, enabling luminescence thermometry with the highest relative sensitivity of 12.3%/K at 298 K and low temperature uncertainty of 0.11 K at 623 K. These findings may gain a vital insight into the design of negative-thermal-expansion RE 3+ -doped phosphors for versatile applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Feng Chen,Qiujun Lu,Youyu Zhang,Shouzhuo Yao
Due to the low abundance of miRNAs and the coordinated regulation of multiple miRNAs toward some biological processes, a method that can sensitively and simultaneously detect multiple miRNAs is needed. Here, a strand displacement dual amplification (SDDA) strategy was developed for multiple miRNAs analyses using a unique single strand-double strand-single strand DNA (sdsDNA), which generated by the target recognition probe hybridizing with the site region probe. During the process of SDDA, miRNA hybridized to the target recognition domain of sdsDNA, thereby releasing the site, which triggered the first strand displacement reaction. This strand displacement event resulted in the release of the other site, triggering the second strand displacement reaction. Both two strand displacement reactions in each assembly circle were integrated for amplified signals, which were tested by a fluorescence resonance energy transfer (FRET) assay. NaYF 4 :Yb,Tm/Er UCNPs and Ti 3 C 2 nanosheets were used as the energy donor-acceptor pair. By employing 1:2 ratio of donor-acceptor, the energy transfer efficiency between NaYF 4 :Yb,Tm/Er UCNPs and Ti 3 C 2 nanosheets could reach 90%, which enhanced signal-to-background ratio. Combining the benefits of dual amplification and efficient energy transfer on miRNAs detection, this assay exhibited a linear range from 5 fM to 100 pM for miRNA-21 and miRNA-10b. Moreover, this assay was applied to estimate the expression of miRNA-21 and miRNA-10b in human hepatoma and hepatocyte cell lines. Therefore, this FRET-based SDDA strategy has been used for highly sensitive detection of multiple miRNAs in cell lysate and facilitates the development of efficient biosensor platform.
✓ 已验证
产品关联
DOI
高影响因子
Science of Advanced Materials
·
2019
·Vol. 11
·期 6
·893-901
·
IF 1.158
Zhang Zhongtao,Zhang Guangkun,Ji Jingtian,Gao Zhonghui
Nuclear magnetic resonance imaging (MRI) has high image resolution and is widely used in the medical field, but it has the problem of inadequate sensitivity. Therefore, contrast material is needed to enhance the image clarity and accuracy of MRI. In order to further improve the cell
resolution of magnetic resonance imaging (MRI), a new contrast agent, BaYbF5/BaGdF5-Tm, Yb, is obtained by using BaYbF5 and BaGdF5 as the main raw materials and using high temperature thermal decomposition method. A layer of polyethylene glycol (PEG) is added to the material
from the point of view of biocompatibility. TEM and XRD are used to characterize the material, and MTT is used to test the cytotoxicity of the material. The material is used in the imaging process of stem cell-Danhong in the treatment of cerebral infarction. Bioluminescence imaging, immunofluorescence
testing and autoradiography are carried out. A large number of tests have confirmed that the material has low cytotoxicity and is similar to the existing contrast agents in MRI imaging. In bioluminescent imaging experiments, using BaYbF5/BaGdF5-Tm, Yb contrast agent can enhance the optical
density of imaging. In autoradiography test, using BaYbF5/BaGdF5-Tm, Yb contrast agent can clearly show the changes of various tissues. In immunofluorescence test, using BaYbF5/BaGdF5-Tm, Yb contrast agent can find more vascular proliferation cells survive. The new contrast agent proposed
in this study can enhance the imaging ability of MRI. Compared with conventional contrast agents, it has higher cell resolution and lower cytotoxicity. It has positive significance for future disease detection in medicine.
研究领域:
医学影像学
·
神经病学
·
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF FLUORINE CHEMISTRY
·
2017
·
IF 2.101
Songxia Yu,Zhiqiang Wang,Ruijun Cao,Lingjie Meng
In this paper, we have developed a series of rare earth fluoride nanocrystals (NCs) that can be used for multimodal imaging applications. Three highly monodisperse and water dispersible NaGdF 4 :Yb,Ln@NaGdF 4 (Ln = Er, Tm, Ho) upconversion luminescence (UCL) NCs with an average size of 75 nm were prepared using a facile and efficient microwave–assisted solvothermal reaction in ethylene glycol (EG). The morphology, crystal structures, size distributions and zeta potentials of the resulting NCs were fully characterized by transmission electron microscopy (TEM), X–ray diffraction (XRD) and Nano–ZS90 Zetasizer. The obtained NaGdF 4 :Yb,Ln@NaGdF 4 (Ln = Er, Tm, Ho) NCs could emit bright blue, green and red luminescence in water upon laser excitation at 980 nm. Furthermore, these core–shell NCs exhibited low cytotoxicity for HeLa and C9H2 cells, separately. Moreover, these NCs also displayed excellent Hounsfield units (HU) values in X–ray computed tomography (CT) imaging and high relaxivity parameters (r 1 ) in magnetic resonance (MR) imaging in vitro . Thus, these small, water–dispersible and biocompatible NCs show excellent potential as contrast agents for UCL/CT/MR multimodal imaging and other biomedical applications.
研究领域:
材料科学
·
生物医学工程
·
影像医学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）