Inorganic and Nano-Metal Chemistry
·
2022
·
IF 1.514
Zhiqiang Ding,Gongsheng Ding,Ling Fang,Zifei Peng
Red nanofluorescent materials based on CaWO4:Eu3+ were prepared by the molten salt method. Spherical CaWO4 particles with a size of 100 nm to 200 nm monodisperse sizes were prepared using different types of calcium salts. The KCl was chosen as the molten salt, under the same other experimental parameters, the obtained CaWO4:Eu3+ particles were more uniform, the diffraction properties were better. With a molar ratio of 15 for molten salt and Calcium salt, more spherical CaWO4:Eu3+ particles were produced small and sand homogeneous size. Using different amount of molten salt, it was found that the larger the amount of molten salt, the weaker the fluorescence property. Finally, by comparing the products obtained by the molten salt method with the solid state reaction method, it is found that the luminescence intensity of the products is 20% higher than that obtained by the solid state reaction method.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2011
·Vol. 40
·期 48
·12818-12825
·
IF 3.647
Xuefeng Zhai,Min Yu,Ziyong Cheng,Zhiyao Hou,Ping'an Ma,Dongmei Yang,Xiaojiao Kang,Yunlu Dai,Dong Wang,Jun Lin
Rattle-type hollow nanocapsules are among of the most promising candidates as drug carriers owing to their huge inner space and multifunctional material combination. In this paper, rattle-type hollow CaWO4:Tb3+@SiO2 nanocapsules with a diameter of 100–110 nm and a wall thickness around 10 nm were fabricated. The hollow silica nanospheres were used as nano-reactors and the luminescent core of CaWO4:Tb3+ was post-filled into the nano-reactors by a vacuum nano-casting route combined with a Pechini-type sol–gel method. Subsequently, doxorubicin hydrochloride (DOX), a model of an anti-cancer drug, is loaded into the CaWO4:Tb3+@SiO2 nanocapsules and their cell cytotoxicity, cancer cell uptake and drug release behavior are investigated in vitro. The prepared multifunctional inorganic nanocapsules show a loading capacity for DOX as high as 124 mg g−1 and sustained-release properties. The release profile of the drug from DOX-loaded nanocapsules can last over five days. Besides, the blank CaWO4:Tb3+@SiO2 shows very low cytotoxicity against cancer cell lines (HeLa cell) while the DOX-loaded nanocapsules exhibit relatively high efficiency for killing of HeLa cells. The rapid cancer cell uptake process is observed by confocal laser scanning microscopy. The results indicate that a rattle-type hollow CaWO4:Tb3+@SiO2 nanocapsule has the potential to be used as drug carrier in therapy. Moreover, it is possible to extend the synthetic strategy in this study to other rattle-type multifunctional composites to meet various demands.
研究领域:
纳米医学
·
肿瘤学
·
药剂学
·
生物材料
·
分子影像
✓ 已验证
DOI
高影响因子
SUPERLATTICES AND MICROSTRUCTURES
·
2015
·
IF 2.097
Renping Cao,Haidong Xu,Dedong Peng,Shenhua Jiang,Zhiyang Luo,Wensheng Li,Xiaoguang Yu
Novel CaWO 4 :Eu 3+ , Mn 2+ red phosphor is synthesized by solid-state reaction method in air. CaWO 4 :Eu 3+ , Mn 2+ phosphor with excitation 268 and 394 nm emits red light with chromaticity coordinates (x = 0.6403, y = 0.3593). The strongest emission bands peaking at ∼615 nm is attributed to 5 D 0 → 7 F 2 of Eu 3+ ion. Strong excitation band peaking at ∼394 nm indicates that the phosphor may be excited by near UV (∼394 nm) chip. Emission intensity of CaWO 4 :Eu 3+ , Mn 2+ phosphor with excitation 268 nm is ∼2 times stronger than that of CaWO 4 :Eu 3+ phosphor owing to energy transfer between Eu 3+ ion and Mn 2+ ion. Energy transfer from WO 4 2 − group and Eu 3+ ion to Mn 2+ ion in CaWO 4 :Eu 3+ , Mn 2+ phosphor may be explained via luminescence properties. Luminous mechanism is analyzed by energy level diagrams of WO 4 2 − group, Mn 2+ and Eu 3+ ion. The paper content is helpful to develop and research other novel phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Haodong Sun,Zuoyi Xiao,Zhenyu Zhao,Yingjie Huang,Shangru Zhai,Qingda An
The construction of an efficient and recyclable photocatalyst for the degradation of antibiotics is still a challenge. In this work, we successfully synthesized porous carbon-supported CaWO 4 nanoparticles (CaWO 4 @C) by solidifying sodium alginate (SA) mixed with Na 2 WO 4 by Ca 2+ ions and subsequent high-temperature carbonization . The introduction of porous carbon significantly reduced the size of CaWO 4 particles, increased the specific surface area for mass transport, and improved visible light utilization. The influence factors of photocatalytic activity were extensively explored through photocatalytic degradation of tetracycline (TC). As a result, the optimized CaWO 4 @C exhibited excellent photocatalytic performance with the TC degradation rate of 94.56% after 60-min visible light irradiation. The TC photodegradation rate constant was calculated to be 0.051 min −1 , which was 30.19-time higher than the pristine CaWO 4 . Besides, the photocatalytic reaction mechanism for degradation of TC was revealed in terms of free radical trapping experiments and electron spin resonance (ESR) techniques.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2019
·
IF 2.155
Xiaoqing Guo,Shuangju Song,Xue Jiang,Xue Wang,Jiahui Guo,Qingwei Song,Yuanyuan Han,Liyong Wang
Eu 3+ activated CaWO 4 (CWO) phosphors were prepared via a modified hydrothermal process. In present work, the phosphors illustrated enhanced emission properties by the assistance of poly acrylic acid (PAA). The phase structure, micromorphology, photoluminescence properties and luminescence enhancement mechanism of the as-prepared samples were investigated. The as-prepared PAA assisted samples exhibited significantly enhanced red emission peaking at 595 nm and emission intensity increased by about 8 times. The results indicated that CWO: Eu 3+ samples could be a potential candidate of red phosphor for white light-emitting diodes (WLEDs).
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
LUMINESCENCE
·
2020
·Vol. 36
·期 1
·237-246
·
IF 1.855
Feng-Nian Wu,Hua-Jian Yu,Yan-Yan Hu,Hua-Di Zhang,Rui Zhang,Jing Li,Bing Liu,Xu-Ping Wang,Yu-Guo Yang,Lei Wei
(Ca 1-x Eu x )WO 4 (x = 0–21 mol%) phosphors were prepared using the classical solid-state reaction method. The influence of Eu 3+ ion doping on lattice structure was observed using powder X-ray diffraction and Fourier transform infrared spectroscopy. Furthermore, under this influence, the luminescence properties of all samples were analyzed. The results clearly illustrated that the element europium was successfully incorporated into the CaWO 4 lattice with a scheelite structure in the form of a Eu 3+ ion, which introduced a slight lattice distortion into the CaWO 4 matrix. These lattice distortions had no effect on phase purity, but had regular effects on the intrinsic luminescence of the matrix and the f–f excitation transitions of Eu 3+ activators. When the Eu 3+ concentration was increased to 21 mol%, a local luminescence centre of [WO 4 ] 2− groups was detected in the matrix and manifested as the decay curves of [WO 4 ] 2− groups and luminescence changed from single exponential to double exponential fitting. Furthermore, the excitation transitions of Eu 3+ between different energy levels (such as 7 F 0 → 5 L 6 , 7 F 0 → 5 D 2 ) also produced interesting changes. Based on analysis of photoluminescence spectra and the chromaticity coordinates in this study, it could be verified that the nonreversing energy transfer of [WO 4 ] 2− →Eu 3+ was efficient and incomplete.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
PHYSICA B-CONDENSED MATTER
·
2022
·
IF 2.988
Yuhong Zhang,Yibin Guo,Xingke Zheng,Pengcheng Wang,Hang Liu
A series of AWO 4 (A = Sr, Ca): Yb 3+ /Tm 3+ /Gd 3+ /Er 3+ phosphors are successfully prepared by solid-state method. In comparison with the samples without Gd 3+ ions, the UC emission intensity of CaWO 4 : 0.5 mol%Tm 3+ /1 mol%Yb 3+ /10 mol%Gd 3+ sample has increased by 104 times (∼475 nm), 71 times (∼655 nm) and 23 times (∼795 nm) due to the shrink of the host lattice with the Gd 3+ ions corporation. Based on the fluorescence intensity ratio (FIR) of non-thermal couple levels(non-TCLs), the temperature sensing characteristics are investigated for AWO 4 (A = Sr, Ca): Yb 3+ /Tm 3+ /Gd 3+ /Er 3+ phosphors. The maximum values of absolute sensitivity and relative sensitivity are 0.09356 K -1 and 1.499% K −1 for CaWO 4 : Yb 3+ /Tm 3+ /Gd 3+ /Er 3+ phosphor. It indicates that the AWO 4 (A = Sr, Ca): Yb 3+ /Tm 3+ /Gd 3+ /Er 3+ phosphors can be applied to develop optical thermometry.
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 THE AMERICAN CERAMIC SOCIETY
·
2012
·Vol. 95
·期 10
·3214-3219
·
IF 2.272
Haoyi Wu,Yihua Hu,Fengwen Kang,Nana Li,Guifang Ju,Zhongfei Mu,Zhongfu Yang
Praseodymium (Pr 3+ ) with rich f energy levels can generate various visible emissions, but the luminescence of Pr 3+ in a CaWO 4 matrix has not yet been studied. In this article, the phosphors of Pr 3+ -doped CaWO 4 were synthesized via a high temperature solid-state reaction, and the photoluminescence (PL) and afterglow properties of Pr 3+ in the CaWO 4 matrix were investigated. The phase identifications of the samples show that an impure monoclinic phase appears when the Pr 3+ concentration is high. The results of PL exhibit the usual Pr 3+ characteristic emissions as well as an emission that is produced by the charge transfer from 5 d of W 6+ to 2 p of O 2− under a shortwave ultraviolet excitation. An intermediate energy transfer occurs during the charge transfer which induces the afterglow. The quenching point of Pr 3+ in CaWO 4 is 2 mol%, corresponding to the critical energy transfer distance of ~20 Å. The quenching mechanism in the Pr 3+ -doped CaWO 4 is the dipole-dipole interaction. The Ca 2+ vacancies ( V Ca ) are the defects that induce the traps and capture holes from O 2− . The thermal energy of holes liberation from V Ca to O 2− results in the charge transfer accompanied by an energy transfer to Pr 3+ , and consequently generates the afterglow. The experimental results also show that the afterglow characteristics of Pr 3+ are prolonged by incorporating Pr 3+ in the CaWO 4 matrix.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Su Zhang,Lingling Lv,Hongjie Wang,Chongyang Zhu,Ran Pang,Jing Feng,Da Li,Guanyu Liu,Lihong Jiang,Chengyu Li
The 0.8CaWO 4 -0.2EuMO 4 (M = Nb, Ta) solid solution and Eu 3+ , Ta 5+ and Nb 5+ single doped CaWO 4 were prepared by a high-temperature solid state reaction technique. Experiments show that the addition of Nb 5+ and Ta 5+ can increase the red luminescence of Eu 3+ in CaWO 4 . In this paper, the composition and structure of solid solution were analyzed by X ray diffraction (XRD), Fourier transform infrared spectrum and Raman spectrum analysis. The luminescence properties of the solid solution were studied by means of stable photoluminescent spectra, diffuse reflectance spectra (DRS), fluorescent decay curves and variable temperature spectra. By combining structural analysis, J-O theoretical calculation and experimental results, we believe that the significant improvement of the emission efficiency comes from the decrease of non-radiation relaxation rate.
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
·
2019
·
IF 2.961
Wei Xu,Yuwei Hu,Longjiang Zheng,Zhiguo Zhang,Wenwu Cao
Optical temperature sensors based on rare earth ions activated luminescent materials have presented their capabilities in thermal reading with good stability and high spatial resolution. The ongoing challenge is to improve the luminescence for further enhancing temperature measurement sensitivity and accuracy. Here, several Er 3+ -Yb 3+ codoped CaWO 4 phosphors are prepared and Cr 3+ ions are introduced, trying to modify the upconverion (UC) emissions from Er 3+ ions. Under the excitation of 980 nm laser, green UC luminescence from 2 H 11/2 and 4 S 3/2 states of Er 3+ is successfully strengthened with Cr 3+ codoping. Through the analysis of characterization by scanning electron microscopy, X-ray diffraction, Raman spectroscopy , and time-resolved spectroscopy, it is found that the dopant of Cr 3+ ions could affect the crystallinity and distort the crystal structure of the as-prepared samples. The thermometry behavior based on green emissions of Er 3+ is studied via fluorescence intensity ratio method. It is interesting to observe that the temperature sensing performance has also been influenced by the incorporation of Cr 3+ . When introducing 9 mol% Cr 3+ ions into Er 3+ -Yb 3+ codoped CaWO 4 phosphors, a maximum sensitivity of about 1.91% K −1 has been achieved. Combined with the intense green luminescence, CaWO 4 : Er 3+ -Yb 3+ -Cr 3+ would be a promising candidate for optical thermometry with excellent measurement sensitivity and accuracy.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2025
·
IF 4.9
Lulu Qiu,Baosheng Cao,Yujie Weng,Qianrui Liu,Yufeng Li,Shaowen Wang,Wenna Zhao,Yangyang He,Bin Dong
The harmonic generation effect, a distinct nonlinear optical phenomenon , exhibits unique properties and has critical applications across multiple fields. However, harmonic generation during optical measurements can introduce significant interference or experimental errors. Here, we investigated the photoluminescence (PL) characteristics of Dy 3+ doped CaWO 4 phosphors under near-infrared (NIR) irradiation. Both characteristic yellow and blue emissions of Dy 3+ and a series of NIR-induced harmonic generation were observed. The study demonstrated that Dy 3+ emissions were excited by harmonic generation originating from the dual-grating configuration of a spectrophotometer. Leveraging the divergent temperature-dependent intensity evolution between Dy 3+ emissions and 1.5th harmonic generation, we proposed a novel ratiometric thermometric strategy based on the luminescence intensity ratio (LIR). This new thermometry achieved optimal temperature sensitivity, with a maximum absolute sensitivity of 74.57 × 10 −4 K −1 and relative sensitivity of 2.21 % K −1 , surpassing conventional ratiometric thermometry relying on thermally coupled energy levels. These findings not only clarified the origin of multiplex harmonic generation and its impact on spectral measurement but also harness harmonic generation for innovative applications in optical thermometry.
研究领域:
光学材料
·
生物医学工程
·
分子成像
·
热疗监测
·
非线性光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2026
·
IF 6.7
Hengji He,Dainan Zhang,Youbin Zheng,Shuyang Ma,Cheng Liu,Qinghui Yang,Huaiwu Zhang
Li/Te co-doped CaWO 4 ceramics with Li:Te molar ratios of 1:0.5, 1:0.75 and 1:1 was prepared to examine composition- and processing-dependent structural evolution and microwave dielectric properties. The Li:Te = 1:1 series was optimized at 890 °C, whereas the Li:Te = 1:0.5 and 1:0.75 series were optimized at 910 °C. XRD and Rietveld refinement, Raman spectroscopy, EPR, XPS, GCIB depth-profile XPS, ICP-OES and electron microscopy were used to correlate phase assemblage, local bonding, chemical-state signals, retained Li, microstructure and dielectric response. Under the respective optimized conditions, the Li:Te = 1:0.75, x = 0.04 ceramic exhibited the highest Q× f value of 89,613 GHz, while the Li:Te = 1:1, x = 0.04 ceramic showed the least negative τf value of −32.06 ppm/°C. GCIB depth-profile XPS revealed composition-dependent depth evolution of the relative Te 4 + - and Te 6+ -related signals, and ICP-OES confirmed systematic differences in total retained Li. In the Li:Te = 1:1 series, electron microscopy identified a Te/O-enriched amorphous interfacial region. Together, these results show that the Li:Te ratio and sintering condition jointly influence local structure, densification behaviour and microwave dielectric properties. The work provides a basis for optimizing the balance between low dielectric loss and temperature stability in CaWO 4 -based ceramics. Furthermore, a preliminary Ag co-firing test further indicates chemical compatibility under the tested condition.
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DOI
高影响因子
危险品化学品经营许可证（带存储）