ANALYTICA CHIMICA ACTA
·
2020
·
IF 5.977
Kang Luo,Haicheng Chen,Qing Zhou,Zhihong Yan,Zhengquan Su,Kang Li
Calcium fluoride (CaF 2 ) quantum dots have many applications in various fields. But there is no report on fluorescent characteristics of CaF 2 quantum dots (CaF 2 QDs). Here, a synthesis of multiple-color emission CaF 2 QDs by changing the temperature, time and raw ratio is reported, by which the CaF 2 QDs with purple, blue, green, and yellow emission can be obtained, respectively. They were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). On this basis, a novel molecular imprinting ratiometric fluorescence sensor (MIR sensor) had been constructed based on the prepared CaF 2 QDs and CdTe QDs, in which the yellow emission CaF 2 QDs was used as a responsive signal material and the red emission CdTe QDs was served as a reference signal material. And the β-CD and methylacrylic acid (MAA) as bifunctional monomers were used for constructing the specific molecularly imprinted polymers (MIPs) in MIR sensor. This MIR sensor was applied for highly selective and excellent sensitive detection of 5-hydroxymethylfurfural (HMF). Under optimum conditions, it exhibited an excellent linear relationship between the fluorescence intensity ratio (I 599 /I 625 ) and the concentration of HMF in the range of 0.1–6.0 μg/mL with a detection limit of 0.043 μg/mL. Finally, the established HMF-MIR sensor was successfully utilized to detect HMF in honey with satisfactory results. This work provided a reference for the application of the CaF 2 QDs and the detection of the furfural substances.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Jing Cao,Ting-Ting Hu,Dan Wang,Jie-Xin Wang
Rare earth ion doped upconverison (UC) luminescence nanophosphors have attracted much attention owing to their wide applications. It is known that homogeneous doping of ions in matrixes and particle size distribution (PSD) determine the luminescent properties. In this study, we reported a novel approach to prepare CaF2:Er3+ and CaF2:Yb3+/Er3+ UC nanophosphors by high-gravity reactive precipitation in a rotating packed bed (RPB) combining hydrothermal process, which is applied for noninvasive temperature detection. The intensified micromixing in the RPB reactor contributes to the achievement of CaF2 nanoparticles with a narrower PSD, more homogeneous doping of Er3+ and Yb3+ ions in the CaF2 matrix, and higher doping efficiency compared to a conventional stirred tank reactor (STR). In particular, the luminescent intensities of the as-prepared CaF2:Er3+(2%) and CaF2:Yb3+(10%)/Er3+(1%) are respectively 12 and 2 times higher than those of the corresponding products prepared in the STR. Furthermore, the maximum absolute sensitivity of RPB-prepared CaF2:Yb3+(10%)/Er3+(1%) is calculated to be 0.0049 K–1, comparable with those of other reported Yb3+/Er3+-codoped materials. This exhibits a great potential of CaF2:Yb3+/Er3+ UC nanophosphors as promising noncontact temperature measuring materials.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2015
·Vol. 17
·期 31
·5900-5905
·
IF 4.034
Bin-Bin Ding,Kun Liu,Fu Zhang,Yang Wang,Sheng Cheng,Yang Lu,Hai-Sheng Qian
Upconversion fluorescent nanostructures with controlled sizes and morphologies have attracted much attention due to their potential and important applications in bioimaging, photodynamic therapy, solar cells and so on. In this work, we describe a facile successive process to fabricate β-NaGdF4:Yb,Er nanocrystals coated with an ultrathin layer of CaF2 with enhanced upconversion fluorescence and stability. The as-prepared β-NaGdF4:Yb,Er@CaF2 nanoparticles were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM, JEM 21000), fluorescence spectroscopy (Hitachi High-Technology Corporation, F-2700) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The as-prepared core–shell nanoparticles show enhanced upconversion fluorescence and superior magnetic resonance (MR) relaxivity. In addition, the as-prepared β-NaGdF4:Yb,Er@CaF2 nanoparticles show enhanced chemical stability after surface functionalization and transfer into aqueous solutions.
研究领域:
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2020
·
IF 14.588
Zhihao Li,Haoran Liu,Rui Wang,Chenhui Ji,Yan Wei,Miusi Shi,Yingqian Wang,Yaping Du,Yufeng Zhang,Quan Yuan,Chunhua Yan
Inorganic ion metabolism plays significant roles in various life processes including signal transduction, substance exchange, and cellular constructions. Regulation and monitoring of ion metabolism offer great promise to modulate biological activities and provide insights into related mechanisms. Here, a synergistic nanodepot based on a bioactive core–shell CaF2 upconversion nanostructure that integrates multiple mineral ions for metabolic regulation was built for the acceleration and monitoring of the biomineralization process. Multiple mineral ions released from the nanodepots can accelerate the growth of inorganic crystals and enhance the production of organic matrixes, synergistically facilitating the regeneration of bone defects in vivo. During the process, such a nanodepot can be constructed to specifically recognize osteoblasts for the monitoring of biomineralization. This nanoprobe represents an efficient strategy to promote and monitor biomineralization-related metabolic activities with applications in fundamental research, disease diagnosis, and regenerative medicine.
研究领域:
材料科学
·
生物材料
·
生物医学工程
·
再生医学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Guoxiang Song,Chaogang Lou,Bowen Shen,Zi Wang,Ruiqi Zhu
We achieved a quantum cutting process in Pr 3+ -Yb 3+ co-doped CaF 2 that converts one visible photon into two near-infrared photons matching the silicon band gap. In this study, the quantum cutting process between Pr 3+ and Yb 3+ was experimentally verified through comparative analysis of the normalized absorption spectrum of Pr 3+ and the near-infrared excitation spectrum of Yb 3+ . Fluorescence lifetime measurements at the optimal doping concentration revealed an energy transfer efficiency of 60.99% from Pr 3+ to Yb 3+ . Temperature-dependent luminescence spectroscopy further estimated the luminescence efficiencies as 64.49% (Pr 3+ ) and 71.41% (Yb 3+ ). Based on these results, the theoretical quantum efficiency of the Pr 3+ →Yb 3+ system was obtained to be about 112.26%, confirming the occurrence of efficient photon down-conversion. Considering the limited energy gain from sunlight due to the narrow-band absorption of Pr 3+ by f-f forbidden transition, Eu 2+ ions were employed to perform broadband sensitization on the quantum cutting process of Pr 3+ -Yb 3+ . Studies have suggested that the incorporation of Eu 2+ can effectively assimilate the 250-400 nm band and transfer energy to Pr 3+ and Yb 3+ , causing them to emit stronger near-infrared spectra. These developed materials are capable of converting ultraviolet-visible photons into near-infrared photons matching the silicon bandgap, which reduces energy loss caused by spectral mismatch and has promising applications in silicon-based photovoltaics.
研究领域:
材料科学
·
光子学
·
无机非金属材料
·
能源材料
·
固体发光
✓ 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
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 29
·16648-16660
·
IF 4.22
Cao Jing,Yang Dan-Lei,Pu Yuan,Wang Dan,Wang Jie-Xin
The good mechanical performances and caries inhibition of resin composites (RCs) are of great importance in dental restoration. Generally, the addition of SiO 2 can improve the mechanical properties of RCs, while the introduction of fluoride (F) ions is capable of preventing caries. In this work, we first report the use of CaF 2 /SiO 2 core–shell nanoparticles (CaF 2 /SiO 2 NPs) as novel fillers for developing RCs with excellent mechanical properties and sustained F release. The results show that the superior performances of RCs can be obtained by filling 50 wt.% CaF 2 /50%SiO 2 NPs, where the flexural strength, flexural modulus, compressive strength, and hardness were, respectively, increased by 111.5%, 41.4%, 61.7% and 66.8%, compared with the RCs filled with CaF 2 nanoparticles. In addition, the initial F-release rate of RCs containing 50 wt.% CaF 2 /50%SiO 2 NPs was 2.5 ± 0.4 μg/(h cm 2 ), while the sustained release rate and the F release ratio were 0.96 ± 0.15 μg/h·cm 2 and 5.22‰ after 1632 h (68 days), respectively. It was much more stable and sustained compared with the counterpart filled with CaF 2 NPs. Therefore, it could be envisioned that CaF 2 /SiO 2 NPs have a great potential as inorganic fillers in dental RCs. Graphical abstract
研究领域:
牙科材料
·
纳米技术
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Xuyang Zhang,Lili Hu,Jinjun Ren
Oxyfluoride glasses in the systems (55 – x)SiO2–(15 + x – z)Al2O3–zLa2O3–10CaO–20CaF2–yErF3 (x = 0, 5, 10, 15; y = 0.5, 1, 1.5; z = 0, 2, 5 mol %) were prepared by conventional melt-quenching method and afterward heated to synthesize transparent glass ceramics containing CaF2 nanocrystals. The local structures of glasses and glass ceramics were characterized by advanced one- and two-dimensional solid-state nuclear magnetic resonance (SSNMR) techniques. La3+ ions were investigated as the diamagnetic mimics for paramagnetic rare-earth ions (REIs) in local structure. The bond connectivities between F– ions and positive ions were probed by 19F magic angle spinning (MAS) NMR spectra and 19F {27Al} double-resonance techniques. F– ions have bond connectivities with Ca2+, La3+, and Al3+ ions, respectively. Ca2+ ions have comparable competition ability in capturing F– ions with La3+ ions, but stronger than Al3+ ions. Multiple F–Al linkages exist in the glasses. 19F static spin echo decay results indicate that F– ions aggregate around Ca2+ ions forming F–Ca linkages-enriched microregions, which form the precursors of CaF2 nanocrystals. However, both La3+ and Al3+ ions can disperse the distribution of F– ions around Ca2+ ions and consequently suppress the crystallization of CaF2. 139La wideband uniform-rate smooth truncation QCPMG (WURST-QCPMG) spectra and the paramagnetic effects of Er3+ on the NMR spectra were measured to reveal the distribution of REIs. The average local environments of most REIs have no significant change during the crystallization of CaF2. Only partial REIs have entered CaF2 nanocrystals after the crystallization, which results in the intensive Er3+ upconversion luminescence. The glass structural evolution during the crystallization is investigated by the evolution of the 19F, 27Al, 29Si, and 139La NMR spectra with the heat treatment conditions. On the basis of the comprehensive glass structure study at the atomic level, the microcrystallization mechanisms of the glasses are revealed.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
BIOMATERIALS
·
2015
·
IF 8.557
Xiaoran Deng,Yunlu Dai,Jianhua Liu,Ying Zhou,Ping'an Ma,Ziyong Cheng,Yinyin Chen,Kerong Deng,Xuejiao Li,Zhiyao Hou,Chunxia Li,Jun Lin
Combining the multi-modal medical imaging with cancer therapy in one single system has attracted the great interests for theranostic purpose. In this paper, CaF 2 :Yb 3+ /Er 3+ /Mn 2+ -poly(2-Aminoethyl methacrylate) (UCHNs-PAMA) hybrid microspheres were successfully fabricated. The synthetic route to the nanocomposite based on a facile hydrothermal method for fabrication of hollow upconversion (UC) nanospheres at first and then post-filling the PAMA interiorly through photo-initiated polymerization. The UCHNs showed orange fluorescence under 980 nm near infrared (NIR) laser excitation , which provided the upconverting luminescence (UCL) imaging modality . Meanwhile, the presence of functional Mn 2+ and Yb 3+ offered the enhanced T 1 -weighted magnetic resonance (MR) and computed tomography (CT) imaging, respectively. Thanks to introducing amine groups-containing PAMA inside the hollow nanospheres, the Pt(IV) pro-drug, c,c,t-Pt(NH 3 ) 2 Cl 2 (OOCCH 2 CH 2 COOH) 2 (DSP), can be conveniently bonded on the polymer network to construct a nanoscale anti-cancer drug carrier. The UCHNs-PAMA-Pt(IV) nanocomposite shows effective inhibition for Hela cell line via MTT assay . In contrast, Pt(IV) pro-drug and UCHNs-PAMA microspheres behave little cytotoxicity to Hela cells. This should be attributed the fact that the anti-cancer ability can be recovered only when Pt(IV) pro-drug was reduced to Pt(II)-drug in cellular environment. Furthermore, the in vivo experiments on small mice also confirm that the hybrid microspheres have relatively low toxic side effects and high tumor inhibition rate. These findings show that the multifunctional hybrid microspheres have potential to be used as UCL/MR/CT tri-modal imaging contrast agent and anti-cancer drug carriers.
研究领域:
纳米医学
·
生物材料
·
癌症治疗
·
医学影像学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Jiajia Xu,Yadong Chen,Xiaojun Li,Yuqing Lei,Chang Shu,Qiaojie Luo,Lili Chen,Xiaodong Li
Dentin bonding based on a wet-bonding technique is the fundamental technique used daily in clinics for tooth-restoration fixation and clinical treatment of tooth-related diseases. Limited bonding durability led by insufficient adhesive infiltration in the demineralized dentin (DD) matrix is the biggest concern in contemporary adhesive dentistry. This study proposes that the highly hydrated noncollagenous protein (NCP)-formed interfacial microenvironment of the DD matrix is the root cause of this problem. Meanwhile, the endogenous phosphate groups of the NCPs are used as pseudonuclei to rapidly induce the formation of amorphous CaF2 nanoparticles in situ in the interfacial microenvironment. The DD matrix is thus reconstructed into a novel porous structure. It markedly facilitates the infiltration of dentin adhesives in the DD matrix and also endows the DD matrix with anticollapsing capability when water evaporates. Whether using a wet-bonding or air-drying mode, the bonding effectiveness is greatly promoted, with the 12 month bonding strength being about twice that of the corresponding control groups. This suggests that the nanoreinforced DD matrix eliminates the dependence of bonding effectiveness on the moisture status of the DD surface controlled only by experiences of dentists. Consequently, this bonding strategy not only greatly improves bonding durability but also overcomes the technical sensitivity of bonding operations of the total-etched bonding pattern. This exhibits the potential to promote dentin bonding and is of great significance to dentistry.
研究领域:
牙科
·
材料科学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 11
·4263-4270
·
IF 8.307
Kunlun Liu,Jun Zhao,Gencai Pan,Yaxian Zhu,Wenwu You,Huafang Zhang,Huiping Gao,Yanli Mao
Lead halide perovskite quantum dots (PQDs) are extremely unstable when exposed to oxygen, water and heat, especially red CsPbBrxI3−x (x = 0, 0.5, 1.2) PQDs. This seriously hinders their practical application. Here, red CsPbBrxI3−x (x = 0, 0.5, 1.2) PQDs have been successfully encapsulated in porous CaF2:Ce,Tb hierarchical nanospheres (HNSs), which not only greatly improved the stability of PQDs, benefitting from the protection of the CaF2 shell, but also maintained the high photoluminescence quantum yield (PLQY) of PQDs, benefitting from the sensitization of Tb3+ ions. More importantly, porous CaF2:Ce,Tb nanoarchitectures can prevent aggregation quenching and anion exchange of PQDs. Therefore, the CaF2:Ce,Tb&CsPbBrxI3−x (x = 0, 0.5, 1.2) composite powder can have high PLQY comparable to that of the PQD powder. In view of this, CaF2:Ce,Tb&CsPbBr1.2I1.8 composite based red light-emitting diodes (LEDs) are prepared, and they are very suitable as a supplementary light source for plant lighting. Furthermore, white LEDs are also prepared by coating the CaF2:Ce,Tb&CsPbBr3 and CaF2:Ce,Tb&CsPbBr1.2I1.8 composite on a 450 nm chip. The optimum luminous efficiency is 61.2 lm W−1, and the color rendering index is 91, which are comparable to the current highest values. This shows that the composite composed of PQDs has great potential in LED lighting.
研究领域:
材料科学
·
纳米技术
·
光电技术
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IRONMAKING & STEELMAKING
·
2024
·
IF 1.7
Jinming Wang,Xiangjun Liu,Wentao Guo,Zengwu Zhao,Zuolin Sun
The rare earth in the rare earth slag can be separated and enriched by heating and melting the rare earth slag and then slowly cooling crystallisation. In this process, it is of great significance to study the effect of chemical composition on the crystallisation of rare earth phase in slag and the effect of slag viscosity on crystal growth. The rare earth slag melt samples were prepared according to the main chemical composition of rare earth slag by using an analytical pure reagent. The effects of CaF2 and La2O3 contents on the phase structure and morphology of rare earth phase in CaO–SiO2–La2O3–CaF2 slags were studied by SEM-EDS and XRD. The relationship between the viscosity of the slag and the crystal growth behaviour was studied by measuring the melt viscosity with the cylinder rotation method. The results show that the rare earth in CaO–SiO2–La2O3–CaF2 slags exists in the form of CaLa4(SiO4)3O. The change of CaF2 and La2O3 content has no effect on the structure of rare earth phase, but the size of rare earth crystal phase changes obviously. With the increase of CaF2 and La2O3 content, the size of rare earth crystal phase increases gradually. CaF2 and La2O3 can reduce the viscosity transition temperature of slag melt and increase the crystallisation temperature range of rare earth phase to promote crystal growth.
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DOI
高影响因子
危险品化学品经营许可证（带存储）