JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Xiaoli Luo,Wu Zhao,Qichen Chen,Mingfeng Zhi
As a matrix material, NaYbF 4 has attracted more and more attention due to its large absorption cross section and high energy transfer efficiency. In this study, lanthanide doped NaYbF 4 upconversion (UC) nano-/micro-crystalline was carefully synthesized by hydrothermal method . The influence of kinds of external conditions, including reaction time, initial reaction solution pH value, organic solvents codoping, and Na + concentration on crystalline phase, size, morphology and especially luminescent property are systematically studied and the possible formation mechanism based on PH values is emphatically proposed. The products of NaYbF 4 with various morphologies range from nanospheres , microprisms, microdisks, hexagonal crown-capped shapes, hexagonal clam-like shapes and hexagonal flower-like shapes were successfully prepared. The results show that the up-conversion luminescence property is positively correlated with the slenderness ratio. Solvents codoping and Na + concentration can greatly improve the luminescence property, especially for red emission. Impressively, the emission colors and intensities might be finely tuned through finely tuning the PH values, solvents co-doping and Na + dosage. Furthermore, this study will be expected to contribute to the synthesis of various morphologies and improving the UC intensity of lanthanide doped crystals.
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 Nano Materials
·
2020
·
IF 0
Chunyu Qi,Li Chen,Yuan Gao,Yue Wang,Jing Li,Ligong Zhang,Yongshi Luo,Xiaojun Wang
Size and size distribution control along with the excitation/emission wavelength manipulation are the most indispensable for both fundamental research and applications of upconverting nanophosphors. In contradiction to the usual Ostwald ripening process, digestive ripening-mediated growth of core–shell nanostructures is observed in a lanthanide-doped ternary fluoride system. Time-dependent size evolution of NaYbF4:Tm@NaYF4 nanoparticles is systematically investigated, and a Ksp-involved growth mechanism is proposed to better understand this unusual phenomenon. The upconversion luminescence (UCL) intensity and branch ratio of near-infrared to visible emission (NIR/VIS) dramatically increase due to the NaYF4 coating but subsequently undergo a decline when an additional SiO2 layer grows outside. As a comparison, an alternant type of core–shell–shell nanostructure, NaYbF4:Tm@SiO2@NaYF4, is further constructed, in which both the UCL intensity and NIR/VIS ratio exhibit an inverse trend. The comparative analysis on the basis of steady and transient spectroscopic data from NaYbF4:Tm, and alternatively coated by silica and NaYF4 nanoshells, respectively, demonstrates that the UCL properties can be regulated through core–shell engineering once the optical behavior of the surface states can be manipulated. The results provide a promising alternative strategy to fabricate a uniform core–shell nanostructure with multicompositions, and this NIRin–NIRout luminescent profile deserves an expectable vision for the subsequent clinical applications of UCL imaging for deep biological tissues.
研究领域:
材料科学
·
生物医学工程
·
光学
✓ 已验证
产品关联
DOI
Nanoscale Research Letters
·
2022
·Vol. 17
·期 1
·1-8
·
IF 5.418
Yuan Maohui,Yang Zining,Yang Xu,Wang Linxuan,Wang Rui,Lan Sheng,Han Kai,Wang Hongyan,Xu Xiaojun
Controlling the upconversion luminescence (UCL) intensity ratio, especially pumped at 808 nm, is of fundamental importance in biological applications due to the water molecules exhibiting low absorption at this excitation wavelength. In this work, a series of β-NaYbF 4 :Er microrods were synthesized by a simple one-pot hydrothermal method and their intense green (545 nm) and red (650 nm) UCL were experimentally investigated based on the single-particle level under the excitation of 808 nm continuous-wave (CW) laser. Interestingly, the competition between the green and red UCL can be observed in highly Yb 3+ -doped microcrystals as the excitation intensity gradually increases, which leads to the UCL color changing from green to orange. However, the microcrystals doped with low Yb 3+ concentration keep green color which is independent of the excitation power. Further investigations demonstrate that the cross-relaxation (CR) processes between Yb 3+ and Er 3+ ions result in the UCL competition. Graphical Abstract
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xiaohong Li,Jiming Dai,Xiaozhen Zhang,Huafeng Liu,Chengzhi Zhou,Renhua Chen
Non-rare earth ion-activated Yb 3+ -rich fluoride matrix luminescent materials exhibit higher absorption efficiency under near-infrared (NIR) laser excitation, and are more suitable for upconversion (UC) photoluminescence and optical heating applications. These materials are highly promising fluorescent self-labeling nano-heaters. In this work, Bi 3+ -codoped β-NaYbF 4 :Tm 3+ UC nanomaterials were synthesized by combining the hydrothermal reaction with the molten salt method. The effects of Bi 3+ doping on the crystalline phase composition, micromorphology, upconversion luminescence (UCL) properties, spectral characteristics , and optical heating performance of the synthesized materials were investigated in detail. The co-doping of 5–20 mol% Bi 3+ was found to significantly enhance the near-infrared (NIR) UCL intensity of NaYbF 4 : Tm 3+ . In particular, t he sample doped with 15 mol% Bi 3+ emitted nearly pure 801 nm monochromatic near-infrared light under 980 nm optical excitation , and its I NIR /I Blue ratio increased dramatically from 0.97 without Bi 3+ doping to 1599. This material exhibited efficient photothermal conversion capability, and the center temperature of the sample can reach ∼147.6 °C under 10 s laser irradiation, achieving a high photothermal conversion efficiency of 129.53 °C W −1 , together with excellent photothermal conversion stability. The mechanism behind the enhanced NIR emission of Bi 3+ -doped nanomaterials was also elucidated based on the energy level transition strategy.
研究领域:
材料科学
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纳米技术
·
光学
·
发光学
·
光热治疗
✓ 已验证
产品关联
DOI
高影响因子
Journal of Nano Research
·
2015
·
IF 0.564
Guo Zhang,Rui Tao Chai,Yu Chen,She Ying Dong,Liang Zhang,Xing Hua Li,Yuan Ru Jiang,Wei Hua Guo
NaYbF4: Yb3+, Tm3+ nanoparticles (UCNPs) capped with oleic acid (OA) have been synthesized via high-temperature solvent reaction. The optimization sample of NaYb0.96Er0.02Tm0.02F4 nanoparticles possess spectral purity (the Snw value is bigger than 0.7) and intense near infrared to near infrared (NIR-to-NIR) upconversion luminescence (UCL) (the power of laser is as low as 3.8 W), which makes them ideal and promising platforms for high contrast bioimaging.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
Materials Today Chemistry
·
2022
·
IF 7.613
Peng Du,Jun Tang,Weiping Li,Laihui Luo,Marcin Runowski
Red-emitting phosphors play a vital role in reinforcing the quality of phosphor-converted white light-emitting diodes. Unfortunately, concentration quenching and unsatisfied thermal stability are still the inevitable shortcomings of the red-emitting phosphors. Herein, we utilized phase transition to simultaneously tailor the concentration quenching and thermal stability of Eu 3+ -activated NaYbF 4 (NaYbF 4 : x Eu 3+ ) nanoparticles , in order to overcome these limitations. With the increasing doping level, the resultant samples undergo a phase transition from cubic to hexagonal phase. Notably, the optimal doping content for Eu 3+ in the NaYbF 4 nanoparticles with cubic phase is 30 mol%. However, when the phase transition occurs, the concentration quenching takes place at a much higher doping concentration, i.e. the optimum content of Eu 3+ in the structure is increased to about 80 mol%. Moreover, with elevating the Eu 3+ content, the local coordination environment of Eu 3+ in the NaYbF 4 host lattice is changed from inversion (centrosymmetric) to non-inversion symmetry (non-centrosymmetric), which is further confirmed by the theoretical calculation results via Judd-Oflet theory. Furthermore, compared with cubic samples, the hexagonal NaYbF 4 :0.8Eu 3+ nanoparticles show improved thermal stability. Importantly, utilizing hexagonal NaYbF 4 :0.8Eu 3+ nanoparticles, a designed white light-emitting diode emits warm white light, with desired color coordinates (0.398,0.374), high color rendering index (86.3), and low correlated color temperature (3537 K). Besides, NaYbF 4 : x Eu 3+ nanoparticles and their flexible polydimethylsiloxane films exhibit potential applications in high-temperature optical anti-counterfeiting. This work may support a new perspective for tailoring the concentration quenching and thermal stability of various phosphors.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Haoli Ji,Xiaoru Dai,Wenyan Zheng,Chen Zhuang,Wenkun Dong,Dong Chen,Shisheng Ling,Xvsheng Qiao,Zhiyu Wang,Xianping Fan,Guodong Qian
Lanthanide-doped upconversion nanoparticles excel in many fields of applications due to their unique anti-Stokes spectroscopic properties, narrow emission bands, and high photochemical stability. Yb-based self-sensitized fluorides nanoparticles have higher absorption efficiency at 980 nm near-infrared laser than Y-based nanoparticles. This enhanced absorption makes NaYbF 4 an outstanding upconversion host material for pumping more photons to high-energy excited states of Tm 3+ that are rich in energy levels. For these purposes, NaYbF 4 :Tm nanoparticles seem to be more favorable for photoluminescence applications. In this study, size-adjustable NaYbF 4 :Tm nanoparticles were prepared using a high-temperature co-precipitation method. Under 980 nm excitation, the upconversion emission spectra appeared four emission bands in visible region. By increasing the size of nanoparticles, we well enhanced upconversion luminescence, indicating that surface quenching sites play a major role in inhibiting upconversion luminescence. In addition, the negative thermal quenching effect of NaYbF 4 :Tm nanoparticles was observed with temperature dependent luminescence spectra, and we found that smaller sized nanoparticles got stronger negative thermal enhancement and better temperature sensing performance. We fitted the luminescence intensity ratio (LIR) between the 1 D 2 → 3 F 4 (451 nm) and 1 G 4 → 3 F 4 (647 nm) transitions of Tm 3+ , where these nanoparticles exhibited both good absolute sensitivity S A (1.38% K −1 , at 453 K) and relative sensitivity S R (2.56% K −1 , at 293 K). These results suggested that NaYbF 4 :Tm nanoparticles could be a good candidate for thermometers even at high temperatures (up to 500 K).
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 MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 2
·1445-1456
·
IF 2.478
Qin Rongpang,Jinhua Xinwei,Hu Jinghua,Zhao Li
Dye-sensitized solar cells (DSSCs) based on conventional P25 photoanode films have poor photovoltaic performance due to their inability to utilize the infrared light, which accounts for 43% of the solar spectrum. To overcome this defect, we prepared the upconversion luminescent material NaYbF 4 : Ho 3+ by the solvent thermal method and incorporated it into the photoanode of DSSCs. The upconversion luminescent material NaYbF 4 : Ho 3+ is a composite multifunctional material that can absorb infrared light and emit different bands of visible light. The composite film formed by doping NaYbF 4 : Ho 3+ in the photoanode film can indirectly utilize infrared light to broaden the spectral absorption range and improve the absorption of photons. The effect of different incorporation ratios of fluorescent materials on cell performance was studied. Optimal performance devices based on optimized ratios of UCNPs achieve a high-power conversion efficiency of 7.52%, an improvement of 28.8% compared to conventional P25 nanoparticle-based DSSCs (5.84%). The improved performance of NaYbF 4 : Ho 3+ -based DSSCs could be attributed to the upconversion luminescence effect, high light-trapping efficiency, low charge transfer resistance, and long electron lifetime. This work provides a new possible way to extend the spectral response range of DSSCs and to prepare high-performance solar cells.
研究领域:
材料科学
·
光伏技术
·
纳米技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 18
·9611-9617
·
IF 2.936
Ji-Wei Shen,Zhiqing Wang,Xiaoxuan Wei,Jiawei Liu,Yinmao Wei
Herein, user-friendly control of the synthesis of sub-10 nm hexagonal (β-) NaYbF4:Er nanocrystals (NCs) with extremely low-level Gd3+ doping (0%, 10 mol%) was achieved. We reveal for the first time that the effective sodium/fluoride levels during the formation of cubic (α-) nuclei are not only controlled by the sodium/fluoride to rare-earth precursor ratios used, but also sensitively restricted by the in situ NaF generation reaction in a sodium oleate-based solvothermal system. Excessive in situ NaF generation will lead to a respective sodium- and fluoride-deficient environment, delayed α-to-β transition and larger β-NCs. Based on these effects, sub-10 nm monodisperse low-level Gd3+-doped β-NaYbF4:Er was obtained with a user-friendly low fluoride dosage by finely balancing this NaF generation reaction and achieving an intrinsic optimized sodium-fluoride level for NC nucleation. Notably, our work represents the first example where the focus is on the competing in situ NaF generation reaction and its use for nucleation regulation, as well as for the user-friendly control of the solvothermal synthesis of sub-10 nm β-NaYbF4:Er.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Wei Gao,Shanshan Han,Boyang Wang,Zeyu Sun,Yanrui Lu,Qingyan Han,Xuewen Yan,Jihong Liu,Jun Dong
Harnessing the precious metal plasmon effect is a powerful way to enhance the upconversion luminescence of rare-earth materials, so it has received extensive attention from researchers. In this study, a series of AMF@SiO 2 @NaYbF 4 : Er 3+ composite structures were constructed with an Au mono-layer film (AMF) as the substrates and SiO 2 as the isolation layer to enhance the upconversion emission intensity of a single NaYbF 4 : 2%Er 3+ microdisk. When the size of Au nanoparticles was 72 nm and the thickness of the SiO 2 isolation layer was 24 nm, the upconversion emission enhancement factor of the single NaYbF 4 : 2%Er 3+ microdisk reached 6.98 under 980 nm laser excitation, due mainly to the enhancement of the local electromagnetic field. The upconversion luminescence properties of a single NaYbF 4 : 2%Er 3+ microdisk were significantly affected by the size of Au nanoparticles, the density of the AMF substrate, and the thickness of the SiO 2 isolation layer. The plasmon-enhanced upconversion luminescence mechanism was studied according to its luminescence properties, dynamic tests, and theoretical simulation. The synergistic effects in the local electromagnetic field, luminescence quenching, and local surface plasmon resonance effect are also discussed. The results of this research provide an invaluable theoretical basis for enhancing the upconversion luminescence of rare-earth materials with the help of AMF substrates.
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
BIOMATERIALS
·
2014
·
IF 8.312
Liangjun Zhou,Xiaopeng Zheng,Zhanjun Gu,Wenyan Yin,Xiao Zhang,Longfei Ruan,Yanbo Yang,Zhongbo Hu,Yuliang Zhao
We developed a facile strategy to obtain a new kind of mesoporous core-shell structured up-conversion nanoparticles (mUCNPs), composed of a NaYbF 4 :2%Er core and a mesoporous NaGdF 4 shell. This mesoporous shell not only enhanced the up-conversion luminescence but also endowed many other functionalities of the nanoparticles such as drug delivery and bio-imaging capabilities. Moreover, after being conjugated with polyethylenimine (PEI) and folic acid (FA), core-shell mUCNPs exhibited good water dispersibility , enhanced drug delivery efficiency, and remarkable targeting ability to cancer cells. To certify the folate receptors (FR)-mediated targeted drug delivery , cell viability assay, cell up-conversion luminescence imaging and flow cytometry analysis were carried out. Furthermore, apart from the application for targeted drug delivery, the as-prepared core-shell mUCNPs could also be employed as the contrast agents for X-ray computed tomography (CT) and magnetic resonance (MR) imaging, because of the strong X-ray attenuation ability of Yb and high longitudinal molar relaxivity ( r 1 ) of Gd in the nanoparticles, providing the potential for simultaneously bio-imaging and cancer-targeting therapy.
研究领域:
生物医学工程
·
纳米医学
·
分子影像学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Optical Materials
·
2024
·
IF 0
Jiaxin Li,Yujiao Zhang,Pengli Wang,Dan Xiao,Cuisong Zhou
Alloyed upconversion nanoparticles (aUCNPs, NaYbF4:10% Er@NaYF4) with high Yb3+ doping were designed to brighten luminescence, exploring multicolor patterns of information encryption. The luminescence intensity of aUCNPs was 2.3 times higher than that of common doped UCNPs reported (dUCNPs, NaYF4:20% Yb, 2% Er@NaYF4). Furthermore, because of the high Yb3+ doping (90%), both green and red emissions of aUCNPs were enhanced, ∼4.2 and ∼17.2 times stronger than that of NaYF4:20% Yb, 10% Er@NaYF4, respectively. The reasons for the aUCNPs having a brightened luminescence were explored by synthesizing four UCNPs with different structures and comparing their luminescence. These are attributed to their unique features: (1) a larger absorption cross section for accumulating energy, (2) more efficient energy transfer between Yb3+ and Er3+, and (3) their inert shell inhibiting surface quenching. Eventually, three colors including yellow, orange, and red were obtained by combining aUCNPs and neutral red (NR) taking advantage of the inner filter effect (IFE), and aUCNPs were thus successfully applied in information encryption with multicolor patterns.
研究领域:
材料科学
·
光学
·
信息安全
✓ 已验证
DOI
危险品化学品经营许可证（带存储）