Time-resolved and excitation-emission matrix
Among the various rare-earth ions, europium (Eu 3+)(4f 6) ion exhibits a narrow and almost monochromatic electric dipole emission transition, 5 D 0 → 7 F 2 …
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Rare-earth-doped electrospun scheelite CaWO4 nanofibers with excitation
Abstract. Scheelite structured AWO 4 compounds (A = Ba, Ca, Pb and Sr) are efficient hosts for rare-earth dopants. In this work, high-aspect-ratio AWO 4 (A = Ba, Ca, Pb and Sr) nanofibers, doped with 5 mol.% Tb and 5 mol.% Eu on A site, were synthesized using a sol-gel electrospinning technique, and their performances as a ratiometric sensor …
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Luminescence excitation mechanisms of rare earth doped …
This excitation mechanism is called excitation by electron impact and it becomes noticeable for rare earth concentrations higher than 1%. The excitation spectra of the luminescence of CeF 3 ( Fig. 8 ) show clearly the electron impact excitations as well as the exciton energy transfer evocated in the preceding section [26] .
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Electron Excitation Energies in the Rare Earth and Actinide …
Calculations of various electronic excitation energies for the rare earth and actinide metals are discussed. Relativistic Hartree-Fock computations for atomic configurations most closely approximating those of the metal are initially performed, and crystal potentials are constructed by means of the renormalized atom method.
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Electronic structure and luminescence characteristics of rare earth
Novel self-activated rare-earth-free Ca 2 Sb 2 O 7 phosphor was synthesized by high-temperature solid-state reaction method. ... Ca 2 Sb 2 O 7 is a ternary antimonate with an intense blue emission under UV excitation. When rare-earth ions are doped in Ca 2 Sb 2 O 7 there exist the possibility of energy transfer from Ca 2 Sb 2 O 7 to rare-earth ...
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Energy-Saving Design and Research of High-Speed …
In recent years, under the background of low carbonization and industrial intelligence, with the rise of new energy sources such as wind energy and solar energy, rare earth permanent magnets have begun to be widely used in generators of these new energy sources. From the perspective of green and sustainable development, permanent …
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(PDF) Analysis of the electron excitation spectra in heavy rare earth …
The energy loss spectra of 75 keV electrons transmitted through thin evaporated foils of heavy rare earths (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in three different chemical states (metal, hydride and ...
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Paradigms and challenges for bioapplication of rare earth
Rare earth (RE) materials, which are excited in the ultraviolet and emit in the visible light spectrum, are widely used as phosphors for lamps and displays. ... After reviewing size control, we consider how diverse applications impose different requirements on excitation and/or emission photons and review recent developments on tuning of UC ...
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Special Issue: Rare earth luminescent materials
Lanthanide-doped inorganic upconversion nanoparticles (UCNPs) excitable with NIR light sources are regarded as promising alternatives with which to circumvent background fluorescence and stray...
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Realization of non-rare earth doped blue-emitting phosphor …
Further, the price of rare earth is expensive and reserves are limited. As a non-rare earth element, the excitation spectrum of Sb 3+ is located in the UV region. Packaging LED with Sb 3+ doped phosphors can effectively avoid the problem of visible light reabsorption, thus improving the luminescence efficiency [26].
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Rare Earth Ion Doped Luminescent Materials: A Review of …
Layered hydroxides and rare earth ions are assembled layer by layer, and combined with pyromellitic acid, rare earth ion doped information encryption material is obtained. Under the excitation of ultraviolet and visible light, layered hydroxides doped with rare earth ions exhibit different color emissions, as shown in Figure 14 .
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Rare Earth Luminescence: Electronic Spectroscopy …
The aim of this chapter is to present concise overview on the key concept of luminescence and electronic spectroscopy of rare earth compounds: energy transfer …
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Double-Emission Ratiometric Fluorescent Sensors Composed of Rare-Earth
Quantum dots (QDs) are a class of zero-dimensional nanocrystal materials, whose lengths are limited to 2–10 nm. Their unique advantages such as wide excitation spectra, narrow emission spectra, and high quantum yield make their application possible in fluorescence sensing, wherein QDs such as CdSe, CdTe, and CdS are used. Indeed, QDs have a …
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Luminescent Nanomaterials Doped with Rare Earth Ions and …
The group of rare-earth elements contains lanthanides, as well as elements such as scandium (Sc), yttrium (Y), and lanthanum (La). Lanthanides are characterized by the occurrence of a gradually filling 4f shell, which lies under the layer of outer 5s, 5p, and 6s shells. In the general form, the electronic configuration of lanthanides can be written …
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Luminescence thermometry with rare earth doped …
Rare earth doped materials have been widely used for luminescent thermometers due to their chemical stability and non-blinking properties. ... excitation or emission of luminescent thermometers in biological windows facilitates real-time temperature monitoring during photothermal therapy or temperature measurement at the …
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Energy Migration Engineering of Bright …
Energy Migration Engineering of Bright Rare-Earth Upconversion Nanoparticles for Excitation by Light-Emitting Diodes. Yeteng Zhong, Yeteng Zhong. CAS Key Laboratory for Biomedical …
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Saturation effects in the excitation spectra of rare-earth …
On the line narrowing in two-photon excitation spectra of rare-earth ions To illustrate the line narrowing of two-photon (TP) excitation lines relative to their one-photon (OP) equivalents, Fig. 5 [22] compares the one- and two-photon 8S712 6j.7~~ high-resolution exci- tation spectra of the 6P712 8S emission of Gd3 + in GdB3O6 at RT. The …
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5
1. Introduction. Rare-earth doped ceramics and glasses have been known as fluorescent materials for lasers [1] and optical amplifiers [2].Also, infrared-to-visible upconversion (UC) [3], [4], [5] to emit visible light with near-infrared (NIR) excitation is a characteristic phenomenon reported mostly for them. As for biological use, by making the …
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Excitation and luminescence of rare earth-doped lead …
The relative distribution of rare-earth ions R3+ (Dy3+ or Ho3+) in the phosphate glass RAl0.30P3.05O9.62 was measured by employing the method of isomorphic substitution in neutron diffraction and ...
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Mesoporous Silica Encapsulating Upconversion Luminescence Rare-Earth
The secondary-excitation fluorescence of Rhodamine B is generated from the upconversion rare-earth fluoride nanorods cores to the fluorescent dyes loaded in the mesoporous silica shells. ... Intense red upconversion luminescence in Er3+-sensitized particles through confining the 1532 nm excitation energy. Journal of Luminescence …
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The origin of highly efficient selective emission in rare-earth …
Because the 4f levels of a rare-earth atom are localized and are not directly involved in bonding interactions, we also assume that the non-radiative excitation of electrons within these levels is ...
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Special Issue: Rare earth luminescent materials
energy levels, which endow rare earth luminescent mate-rials with many fascinating optical properties over a broad spectral region ranging from the ultraviolet (UV) to the near …
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Energy Transfer Between Rare‐Earth Ions
Fluorescence quenching effects caused by multipolar energy‐transfer interactions between rare‐earth ions are examined. Transfer between remote ions by way of transitions that are matched in energy appears to be essentially dependent upon concentration alone (e.g., Sm 3+ self‐quenching) while transfer by non‐resonant mechanisms can show a strong …
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Rare earth luminescence: A way to overcome
Optically excited rare earth doped semiconductors suffer from the so-called concentration quenching effect, 1–4 i.e. the intensity of the rare earth luminescence decreases with increasing dopant concentration. This effect dominates if the excitation energy is transferred between many ions in the time necessary for the radiative decay …
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Europium(III) complex with powerful antenna ligands: …
The mechanism of excitation energy migration in coordination sphere is a key problem of the modern spectroscopy and photochemistry. A great number of investigations are devoted to study of various factors which influence on intensification of f-f transitions in lanthanide ions and excitation energy degradation on rare-earth complexes.
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Near infrared excitation and emission in rare earth MOFs
An isoreticular series of anionic rare earth MOFs with fcu topology was synthesized using 10 different rare earth elements (Y3+, Eu3+, Gd3+, Tb3+, Dy3 Jump to main content . Jump to site search . Publishing. ... Near infrared excitation and emission in rare earth MOFs via encapsulation of organic dyes C. Liu, S. V. Eliseeva, T. Luo, ...
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Excitation mechanisms and optical properties of rare …
The optical activity of rare-earth ions in semiconductors is discussed taking into account the large 4f-level correlation energy. In addition to crystal-field effects, three …
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Analysis of the electron excitation spectra in heavy rare earth …
2014 The energy loss spectra of 75 keV electrons transmitted through thin evaporated foils of heavy rare earths (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in three different chemical states (metal, hydride and oxide) exhibit two main peaks due to collective « plasmon » excitations in the 10-17 eV energy range and to inner 5p excitations between 30 and 40 eV. A …
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Covalent organic frameworks decorated by rare earth ions
The excitation spectrum of TGH + ⋅PD:Eu ... Rare earth ions and their composites have been widely studied, so it is necessary to investigate the reported rare earth composites, and then select the appropriate rare earth ions to combine with COFs according to the actual needs. Third, the combined use of multiple metal ions, including …
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(Invited) Excitation Mechanism of Rare Earth Ions in …
The excitation cross section of rare earth ions is orders of magnitude higher in silicon-rich amorphous alloys than in ordinary oxides. Energy transfer is often very …
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