CRYSTAL RESEARCH AND TECHNOLOGY
·
2022
·Vol. 57
·期 4
·2100162
·
IF 1.599
Yanli Ding,Zhaohan Li
The low luminous efficiency of upconversion materials limits their practical applications in various fields. The present study focuses on the efficient upconversion enhancement of β-NaYF 4 :Yb,Er induced by Bi 3+ doping. The XRD and SEM results show that introducing Bi 3+ into the matrix lattice changes the microstructure and particle size of the crystal. The photoluminescence spectra show that at 6% Bi 3+ doping, the red and green emission intensities are enhanced by 12 and 8 times, respectively. The reason could be the lattice distortion caused by Bi 3+ doping, breaking the partial forbidden transition of rare-earth ions. The fluorescence lifetime measurement reveals that the Bi 3+ doping changes the environment around erbium ions, affecting the energy level lifetime of erbium ions, explaining the luminescence dynamics law. The present study provides a facile route to achieve nano/microstructures with intense upconversion luminescence with potential applications in optoelectronic devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2016
·Vol. 3
·期 8
·1082-1090
·
IF 4.532
Min Li,Xiaoyang Liu,Li Liu,Bing Ma,Benxian Li,Xudong Zhao,Wenming Tong,Xiaofeng Wang
A series of Yb3+/Tm3+ co-doped β-NaYF4 (β-NaYF4:Yb,Tm) crystals have been successfully synthesized via the molten salt synthesis (MSS) method. A unique strong green emission of Tm3+ was observed, which cannot be obtained by any other method. The red, green and blue (RGB) light emissions have been obtained simultaneously in the presence of a single activator (Tm3+). The influencing factors of crystal growth have been studied in detail, in order to understand the change of the transition probabilities of Tm3+. Subsequent studies indicate that the RGB light emissions of Tm3+ can be effectively tuned by varying the concentration of sensitizers (Yb3+ and Mn2+) and the reaction time. Consequently, the effective multicolor upconversion (UC) luminescence was obtained, especially a strong white light, which was not obtained in the β-NaYF4:Yb,Tm system earlier. To our knowledge, it is the first time that the UC properties in the β-NaYF4:Yb,Tm system have been investigated by altering the transition probabilities at the same energy level of Tm3+.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2018
·Vol. 6
·期 38
·10226-10232
·
IF 5.976
M. Yuan,R. Wang,C. Zhang,Z. Yang,W. Cui,X. Yang,N. Xiao,H. Wang,X. Xu
Exploiting new transitions in the visible light range is important in the development of advanced color displays, superior laser materials, and novel optical devices. Here, for the first time, we observed several intensive upconversion (UC) emission bands at 382, 472, 506, 560, and 618 nm from a single β-NaYF4:Yb/Er microcrystal via saturated excitation. Compared to the traditional red (650 nm) and green (545 nm) UC emissions, these new emission bands intensify rapidly as the excitation intensity increases, which leads to full-color UC luminescence in the visible region. Nearly white luminescence was elicited from a single microcrystal with a relatively high excitation power. Moreover, the mechanism of these newly observed UC emissions was elucidated by examining the energy migration. It was also found that these microcrystals exhibit waveguide-transmission characteristics and are transparent to their own UC emissions. These findings provide a basis for further exploration of the silent transitions of other rare-earth-ions and demonstrate the potential for using β-NaYF4:Yb/Er microcrystals in a variety of applications in color display and waveguide-based optical devices.
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 Nanomaterials
·
2012
·
IF 1.376
Suli Wu,Yanhui Ning,Shufen Zhang
Novel chelating ligands are very significant for preparing nanocrystals with different morphologies and applications. In this paper, we directly introduced amine groups onto UCNPs by choosing a new chelating ligand tetraethylene pentamine (TEPA) to synthesis
N
a
Y
F
4
:Yb, Er through hydrothermal method. The influences of rare earth concentration, the ratio of RE/TEPA, solvent composition, and reaction time on the morphology and fluorescence intensity of the as-prepared
N
a
Y
F
4
:Yb, Er samples were systematically investigated and discussed. Field emission scanning electron microscopy (FE-SEM), powder X-ray diffraction (XRD), and upconversion luminescence spectroscopy were used to characterize the product. It was found that rare earth concentration, ratio of RE/TEPA, solvent composition, and reaction time were all responsible for the luminescent intensity and morphology.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 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
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
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
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Chuanying Wang,Xianhua Cheng
In this work, β-NaYF 4 :Yb,Er upconversion (UC) film was successfully prepared on silicon (Si) substrate via self-assemble method for the first time. The chemical composition and surface morphology of the UC film were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA), X-ray power diffraction (XRD), and scanning electron microscopy (SEM) measurements. To investigate the effects of KH-560 primer film and chemical reactions on the UC luminescence properties of β-NaYF 4 :Yb,Er UC film, decay profiles of the 540 nm and 655 nm radiations were measured. Furthermore, tribological test was applied to qualitatively evaluate the adhesion of the UC film. The results indicate that the UC film has been successfully prepared on Si substrate by covalent chemical bonds. This work provides a facile way to synthesize β-NaYF 4 :Yb,Er UC film with robust adhesion to the substrate, which can be applicable for other UC films.
研究领域:
材料科学
·
光学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2022
·
IF 6.562
Yunfei Ma,Wenhui Yue,Zehong Xu,Ziwei Ye,Jinlong Zhang
Composite nanoparticles consisting upconversion nanoparticles (β-NaYF 4 :Yb/Er) and nitrogen doped TiO 2 nanoparticles were constructed via a chemical assembly method. Efficient energy transfer was enabled since the upconverted energy matched up with the band gap of N-TiO 2 . This enables the resulting composite nanoparticles to possess excellent Rhodamine B (RhB) degradation activity under near infrared (NIR) light irradiation.
研究领域:
材料科学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 10
·4806-4813
·
IF 3.925
Jie Song,Leilei Sun,Hongchao Geng,Wenlong Tan,Deshuai Zhen,Qingyun Cai
β-Phase NaYF4:Yb,Tm,Gd up-conversion nanorods (UCNRs) with high uniformity were synthesized by a solvothermal method. The optimal fluorescence intensity of UCNRs was explored. After further modification with Materials of Institute Lavoisier-100(Fe) (MIL-100(Fe)) by the layer-by-layer self-assembly method, near-infrared light-triggered UCNR@MIL-100(Fe) nanomaterials with excellent antibacterial performances were constructed. A core–shell structure was constructed and confirmed by transmission electron microscopy (TEM). Reactive oxidizing species (ROS) detection indicated that the nanomaterials owned good photodynamic efficacy. The antibacterial experiments showed that the nanomaterials with 980 nm light irradiation and hydrogen peroxide (H2O2) had good antibacterial activity against Gram-negative and Gram-positive bacteria. Under 980 nm laser excitation, UCNRs generated ultraviolet and visible light to activate MIL-100(Fe) and induced a photo-Fenton reaction, which further produced oxygen species for antibacterial applications.
研究领域:
纳米技术
·
材料科学
·
生物医学工程
·
化学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2012
·
IF 2.08
Wanyue Shao,Ruinian Hua,Wei Zhang,Yue Tian,Jun Zhao,Liyan Na,Jicheng Yu,Zhengang Sun
Carboxylic acid-functionalized Yb 3 + /Er 3 + co-doped α - and β -NaYF 4 nano-/micro-spheres were prepared through a simple poly(acrylic acid) (PAA)-assisted hydrothermal process. Bovine serum albumin (BSA) protein was conjugated with Yb 3 + /Er 3 + co-doped α -( β -)NaYF 4 upconversion phosphors via free carboxylic acid groups on the surface of phosphors. The final products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), infrared (IR) spectrophotometer, ultraviolet (UV) spectrophotometer and photoluminescence spectroscopy (PL). XRD results showed that pure α -NaYF 4 :Yb 3 + , Er 3 + nanospheres could be obtained via PAA assisted hydrothermal process at the pH value of 4–5 and 160 °C for 1–4 h. The obtained product is a mixture of α and β phases NaYF 4 :Yb 3 + , Er 3 + when the reaction time increased from 5 to 24 h. When the solution was treated at 200 °C for 8–24 h at the pH value of 8–9, pure β -NaYF 4 :Yb 3 + , Er 3 + microspheres were obtained. The FE-SEM results showed that the morphology of pure α -NaYF 4 :Yb 3 + , Er 3 + was spherical nanoparticles with an average diameter of about 70 nm and the pure β -NaYF 4 :Yb 3 + , Er 3 + was microsphere with an average diameter of about 700 nm, which is composed of spherical nanoparticles (30 nm). The FT-IR and UV spectra showed that BSA had been conjugated with α -NaYF 4 :Yb 3 + , Er 3 + upconversion phosphors. The luminescence properties of α -( β -) NaYF 4 :Yb 3 + , Er 3 + phosphors were also studied. Under 980 nm excitation, the upconversion luminescence (UCL) intensity of β -NaYF 4 :Yb 3 + , Er 3 + microspheres was much stronger than that of α - NaYF 4 :Yb 3 + , Er 3 + nanoparticles. Moreover, both red and green upconversion were ascribed to the two-photon process.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子