JOURNAL OF ALLOYS AND COMPOUNDS
·
2015
·
IF 2.999
Chuanying Wang,Xianhua Cheng
β-NaYF 4 :Yb 3+ /Er 3+ microcrystals codoped with Cr 3+ ions were prepared for the first time via a facile hydrothermal method . The influence of doping concentration of Cr 3+ ions on growth and upconversion (UC) luminescence properties of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals were investigated in detail. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra and photoluminescence (PL) spectra were used for characterization. The results demonstrated that the morphology and size of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals were influenced by doping concentration of Cr 3+ ions, the possible mechanism was proposed. The UC intensity of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals was significantly enhanced by doping of Cr 3+ ions. In contrast to β-NaYF 4 :Yb 3+ /Er 3+ microcrystals without doping of Cr 3+ ions, the green and red emission intensities of the microcrystals codoped with 15 mol% Cr 3+ ions were enhanced by 16 and 7 times, respectively. The enhancement of the UC intensities should be ascribed to the distortion of local symmetry around Er 3+ ions, the UC mechanism was discussed. This work will be helpful for improving the UC intensity of other lanthanide-doped UC nano- and micro-crystals.
研究领域:
材料科学
·
无机化学
·
光功能材料
·
纳米医学
·
生物成像
·
分子影像学
·
光学材料
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 28
·12201-12207
·
IF 3.288
Yan Qiao,Xionglin Zhou,Hongchao Geng,Leilei Sun,Deshuai Zhen,Qingyun Cai
A β-NaYF4:Yb,Er,Gd nanorods@1T/2H-MoS2 nanocomposite was fabricated and used for photocatalytic sterilization under illumination from single near-infrared (NIR) light. Approximately 99.3% of Escherichia coli were killed effectively by 15 min irradiation of NIR light at a dose of 40 μg mL−1. The effective bactericidal activity is ascribed to the high upconversion luminescence efficiency of β-NaYF4:Yb,Er,Gd and the layered two-dimensional nanosheet structure of 1T/2H-MoS2. Under 980 nm light irradiation, β-NaYF4:Yb,Er,Gd emits visible light, which is absorbed by MoS2, producing strongly oxidative holes and reductive electrons. Photogenerated electron–hole pairs were able to react with H2O, O2 and OH− to produce reactive species in aqueous solution. These reactive species are strong nonselective oxidizing agents for sterilization.
研究领域:
材料科学
·
纳米技术
·
光催化
·
细菌学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2021
·
IF 6.789
Ying Zhang,Yujie Luo,Shiqi Fu,Xiulong Lv,Qian He,Fangying Ji,Xuan Xu
UVC (wavelength < 280 nm) has a wide range of applications in the field of water disinfection due to its excellent bactericidal performance. In this work, we synthesized an upconversion luminescent material, β-NaYF 4 : Pr 3+ , Li + (NYF), which can generate UVC, and compounded it with a BiOCl photocatalyst to synthesize β-NaYF 4 : Pr 3+ , Li + @BiOCl (NYF-Bi) with a core-shell structure. The NYF-Bi composite material can be driven under visible light and has high photocatalytic activity . The bactericidal performance of NYF and NYF-Bi were evaluated using Escherichia coli , Staphylococcus aureus , Shigella and Salmonella . The NYF-Bi composite material killed 99.99% of E. coli under visible light (λ ≥ 420 nm) within 180 min and maintained high germicidal efficacy after 4 cycles. Finally, we deduced the sterilization mechanism of the NYF-Bi composite material through carrier dynamics studies and catching agent experiments. The death of bacteria was mainly caused by UVC light and active species , including h + , OH, and O- 2. This research provides a new material for water disinfection.
研究领域:
环境科学
·
材料科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2021
·Vol. 11
·期 2
·184
·
IF 4.146
Huang Zhou,Fengjiao He
β-NaYF4:Yb,Er,Gd fluorescent nanorods were successfully coupled to a reduced TiO2(UCNPs@R-TiO2) nanocomposite and applied to visible-light catalytic sterilization under 980 nm near-infrared (NIR) light illumination. The UCNPs (β-NaYF4:Yb,Er,Gd) absorb the NIR light and emit red and green light. The visible light can be absorbed by the R-TiO2(Eg = 2.8 eV) for the photocatalytic reaction. About 98.1% ofEscherichia coliwere effectively killed upon 12 min of NIR light irradiation at a minimum inhibitory concentration (MIC) of 40 μg/mL UCNPs@R-TiO2nanocomposite. The bactericidal properties were further evaluated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. We found that the high bactericidal activity was due to the synergistic effect between the UCNPs and R-TiO2. Moreover, the UCNPs show excellent upconversion luminance properties, and the introduction of visible-light-absorbed R-TiO2nanoparticles (2.8 eV) was conducive to the efficient separation and utilization of photogenerated electron-hole pairs.
研究领域:
材料科学
·
微生物学
·
光化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Lele Qiu,Yulin Yang,Guohua Dong,Debin Xia,Mengru Li,Xiao Fan,Ruiqing Fan
As for the solution-processed MAPbI 3 film, the pinholes and gaps are an inevitable and undesirable phenomenon, which can usually lead to serious interface charge recombination due to the penetration of hole transport materials in perovskite solar cells (PSCs). Herein, a hydrophobic β-NaYF 4 :Yb,Er up-conversion ultrathin layer with particle size ca. 6 nm was first applied to modify the MAPbI 3 film for optimizing the surface of perovskite film. Thereby, the corresponding PSCs yield a significantly enhanced power conversion efficiency of 15.17% compared with that (13.32%) of the pristine PSCs. Furthermore, the PSCs also have a good stability in air atmosphere (relative humidity ≤45%) because of the introduction of this hydrophobic material. After a series of detailed investigations and comparison, it can be easily concluded that the filled pinholes and gaps in perovskite films via β-NaYF 4 :Yb,Er nanoparticles is the main reason for the performance enhancement of the β-NaYF 4 :Yb,Er based PSCs, which can result in an enhanced hole extraction efficiency and reduced interface charge recombination. As a conclusion, it is a feasible and effective approach for improving the photovoltaic performance of PSCs by filling up the pinholes and gaps in perovskite films with up-conversion ultrathin layers.
研究领域:
材料科学
·
能源科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2025
·
IF 7
Mingxing Li,Wenda Zhang,Xiaoge Wang,Xiaofan Cao,Chunjun Liang,Xiaojun Kuang,Jing Ju,Fangtian You
Despite remarkable progress in the synthesis of rare-earth nanomaterials, achieving precise control over the distribution of lanthanide ion (Ln3+) dopants remains a formidable challenge. Previous studies that utilized NaYF4 with mixed cation occupancy have offered valuable insights into nonuniform elemental doping and its influence on the emission properties of the materials. However, the complex interplay among cation distribution, structural transformation, and luminescent characteristics has not been fully understood and elucidated. This lack of comprehensive knowledge significantly hinders the optimization of the performance of nanomaterials. In this study, the structural transformation of individual β-NaYF4:Eu3+ nanoparticles under electron beam irradiation was systematically investigated. A discovery was made regarding the transition to a cubic phase. Elemental analysis of the pristine samples revealed that sodium was enriched at the edges of the nanoparticles. This sodium enrichment seemingly initiates the structural transition, which propagates from the surface toward the interior of the particles. Correlated cathodoluminescence electron microscopy (CCLEM) was employed in this research. The results confirmed that the emission intensity is highly correlated with the elemental distribution. Moreover, the structural disorder within the cubic phase leads to a decrease in the site symmetry compared to the theoretical Eu3+ luminescence. Overall, this study provides a more in-depth understanding of how elemental distribution impacts both the structural features and luminescent behavior of these materials. As a result, it makes a significant contribution to the development of optimized nanomaterials with enhanced performance.
研究领域:
纳米材料科学
·
发光材料
·
电子显微学
·
固态化学
·
稀土掺杂
✓ 已验证
产品关联
DOI
高影响因子
Biomedical Optics Express
·
2015
·Vol. 6
·期 5
·1857-1866
·
IF 3.648
Jing Liu,Ruitao Wu,Nana Li,Xin Zhang,Qiuqiang Zhan,Sailing He
It is challenging to achieve deep microscopic imaging for the strong scattering in biotissue. An efficient three-photon luminescence can effectively increase the penetration depth. Here we report that β-NaYF4: Er3+/NaYF4 UCNPs were excited by a 1480-nm CW-laser and emitted 543/653-nm light through a three-photon process. With the merit of the hexagonal crystal phase, sub-milliwatt laser power was utilized to excite the UCNP-probed cells to minimize the heating effect. The polymer-coated UCNPs were shown to be harmless to cells. The deep, high contrast in vitro microscopic imaging was implemented through an artificial phantom. Imaging depth of 800 μm was achieved using only 1.5 mW excitation and a 0.7 NA objective. The green/red emission intensities ratio after penetrating the phantom was studied, indicating that longer emission wavelength is preferred for deep multiphoton microscopy. The proposed and demonstrated β-UCNPs would have great potential in three-photon microscopy.
研究领域:
生物医学工程
·
光学成像
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2021
·Vol. 23
·期 21
·3892-3900
·
IF 3.545
Dandan Ju,Xiaoli Gao,Shouchao Zhang,Yang Li,Wenjing Cui,Yinhui Yang,Mingyan Luo,Shujing Liu
Temperature is one of the physical parameters that affects the emission luminescence properties of upconversion (UC) materials. Temperature-dependent emission color tuning and good temperature sensitivity in multifunctional β-NaYF4:Yb/Er@β-NaYF4:Yb/Tm microcrystals were achieved under 980 nm excitation. Based on the different emission bands (blue, green and red bands) and spectral sensitivities of the core–shell structured microcrystals to temperature, intense white-light emission was obtained at room temperature and a real-time naked-eye recognizable emission color change from white to the purplish-pink region was realized with the temperature increasing from 300 to 500 K. Furthermore, optical temperature sensing properties of the sample with good sensitivity (from 0.0034 to 0.0044 K−1) were investigated by using a fluorescence intensity ratio between 521 nm (2H11/2 → 4I15/2 transition) and 540 nm (4S3/2 → 4I15/2 transition) in the temperature range from 300 to 500 K. The results indicate that the sample has high sensitivity in a relatively wide range of temperature intervals, especially in the low temperature region. We believe that the multifunctional core–shell structured microcrystals exhibit promising applications in white-light emitting diodes, the anti-counterfeiting field, and temperature sensing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Jingxin Ding,Huazhen Liao,Libin Pang,Deping Wang,Song Ye
Rare earth ions doped core-shell thermometers exhibit improved up-conversion emission behaviors, while the thermal sensitivity is not higher than the corresponding core-only structured luminescent thermometers via the thermal coupled levels based luminescence intensity ratio (LIR) technique. In this work, the core-only β-NaYF 4 : 16Yb 3+ , 4Er 3+ (C–4Er) up-conversion nanoparticles (UCNPs) and the sub 25 nm core-shell β-NaYF 4 : 16Yb 3+ , 4Er 3+ @0.5NaGdF 4 (CS–4Er@0.5Gd) and β-NaYF 4 : 16Yb 3+ , 4Er 3+ @1NaGdF 4 (CS–4Er@1Gd) UCNPs have been successfully synthesized by seed-mediated growth methods for temperature detection. The spectral study indicated that the up-conversion luminescence intensity of CS-4Er@0.5Gd and CS-4Er@1Gd was obviously enhanced compared withC-4Er. Luminescence intensity ratio originated from thermally coupled Stark sublevels (Stark-LIR) of Er 3+ ( 2 H 11/2 (1)(2), 4 S 3/2 (1)(2)(3)) of CS-4Er@0.5Gd and CS-4Er@1Gd has been firstly applied to calculated the relative thermal sensitivity (S R ) of core-shell UCNPs. As a result, S R of CS-4Er@1Gd is the largest among the considered UCNPs, and is increased from 10.95 × 10 −3 /K (LIR) to 17.80 × 10 −3 /K (Stark-LIR), indicating that with Stark-LIR techniques, the nano core-shell sensors behave a larger S R than core-only structured thermometers. This work may lead to an appropriate approach to improve the temperature sensitivity of core-shell thermometers for temperature sensing.
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
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2014
·Vol. 14
·期 5
·3726-3730
·
IF 1.339
Guo Xingyuan,Song Weiye,Wang Jianshuo,Shi Feng,Qin Weiping
β-NaYF4:Yb3+, Tm3+/ZnO core/shell nanoparticles (NPs) were synthesized via a high temperature thermal decomposition method. The as-synthesized core/shell NPs were characterized by X-ray diffraction (XRD), transmission electron microscopy
(TEM), and upconversion luminescence spectra (UCL). Under 980 nm laser excitation, the measured intensity of upconversion luminescence (1I6→3H6, 1I6→3F4, and 1D2→3H6)
was different with and without ZnO. During the sample preparations, changing the ratio of the solvent affected the ZnO UV absorption efficiency. The results show that the NIR light can be used as the driving source to excite ZnO, thus extending utility rate to the NIR spectral region and enhancing
the light harvest rate.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
PubMed
高影响因子
Materials Research Express
·
2023
·Vol. 10
·期 8
·086201
·
IF 2.3
Bing Liu,Jingheng Liang,Lili Wang,Zian Cheak Tiu
β-NaYF4: Yb3+/Tm3+/Zr4+ microcrystals are synthesized by a facile hydrothermal route. The up-conversion (UC) luminescence and photoelectric effects are enhanced simultaneously with the introduction of Zr4+ ions under IR excitation. With the Tm3+ ions fluorescence spectra under 980 nm excitation, the blue and red emissions reached the highest intensity in the case of 4 mol% Zr4+ doping. Taking the advantage of Zr4+ stimulates the free electrons transfer from the valence band (VB) to the conduction band (CB) in β-NaYF4:Yb3+/Tm3+/Zr4+ microcrystals, the photocurrent reached the highest intensity in the case of 4 mol% Zr4+ doping at 780 nm excitation. The β-NaYF4: Yb3+/Tm3+/Zr4+ microcrystals with both enhanced UC luminescence and photoelectric properties are highly potential to contribute in photovoltaic and infrared sensors application.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Laser & Photonics Reviews
·
2014
·Vol. 8
·期 4
·575-582
·
IF 9.313
Wu Suli,Liu Ye,Chang Jie,Ning Yanhui,Zhang Shufen
Upconversion emission intensity and morphology are both important features of NaYF 4 :Yb 3+ , Er 3+ microcrystals. In this paper, myristic acid (MA) is selected as a novel stabilizing ligand to synthesize NaYF 4 :Yb 3+ , Er 3+ through a facile hydrothermal method. Upconversion fluorescence spectra indicate that the emission intensity of product prepared with MA as ligand has increased dramatically compared with the sample prepared using commonly used oleic acid (OA) as ligand. Field emission scanning electron microscopy (FE-SEM) results display that the morphology of NaYF 4 :Yb 3+ , Er 3+ obtained using MA as ligand can be tuned from nanodisk, nanorod to nanotube. Especially, nanotube with clear caves can be prepared directly with proper concentration of base (NaOH). And powder X-ray diffraction (XRD) analysis reveals a relationship between the phase transformation process and the amount of NaOH. With increasing the amount of NaOH, the transition process of cubic phase to hexagonal phase is accelerated. The effect of F − and OH − on the fluorescence properties of NaYF 4 :Yb 3+ , Er 3+ are studied systematically. A gradual increase of the amount of NaF results in a regular increase of the emission intensity. On the contrary, the emission intensity decreases with increasing the amount of NaOH. In addition, reasonable explanations of the influence of F − and OH − on emission intensity are given as well.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）