Simple Preparation of LaPO4:Ce, Tb Phosphors by an Ionic-Liquid-Driven Supported Liquid Membrane System

In this work, LaPO4:Ce, Tb phosphors were prepared by firing a LaPO4:Ce, Tb precipitate using an ionic-liquid-driven supported liquid membrane system. The entire system consisted of three parts: a mixed rare earth ion supply phase, a phosphate supply phase, and an ionic-liquid-driven supporting liquid membrane phase. This method showed the advantages of a high flux, high efficiency, and more controllable reaction process. The release rate of PO43− from the liquid film under different types of ionic liquid, the ratio of the rare earth ions in the precursor mixture, and the structure, morphology, and photoluminescence properties of LaPO4:Ce, Tb were investigated by inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, Raman spectra, scanning electron microscopy, and photoluminescence emission spectra methods. The results showed that a pure phase of lanthanum orthophosphate with a monoclinic structure can be formed. Due to differences in the anions in the rare earth supply phase, the prepared phosphors showed micro-spherical (when using rare earth sulfate as the raw material) and nanoscale stone-shape (when using rare earth nitrate as the raw material) morphologies. Moreover, the phosphors prepared by this method had good luminescent properties, reaching a maximum emission intensity under 277 nm excitation with a predominant green emission at 543 nm which corresponded to the 5D4-7F5 transition of Tb3+.

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A simple preparation method for rare-earth phosphate nano materials using an ionic liquid-driven supported liquid membrane system

Journal of Industrial and Engineering Chemistry ◽

10.1016/j.jiec.2017.06.017 ◽

2017 ◽

Vol 54 ◽

pp. 369-376 ◽

Cited By ~ 4

Author(s):

Panpan Zhao ◽

Fan Yang ◽

Zhigang Zhao ◽

Qiuxiao Liao ◽

Yang Zhang ◽

...

Keyword(s):

Ionic Liquid ◽

Rare Earth ◽

Liquid Membrane ◽

Preparation Method ◽

Membrane System ◽

Supported Liquid Membrane ◽

Nano Materials ◽

Simple Preparation ◽

Rare Earth Phosphate

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Liquid-Liquid Extraction of Indium(III) from the HCl Medium by Ionic Liquid A327H+Cl− and Its Use in a Supported Liquid Membrane System

Molecules ◽

10.3390/molecules25225238 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5238

Author(s):

Francisco José Alguacil

Keyword(s):

Ionic Liquid ◽

Liquid Membrane ◽

Membrane System ◽

Liquid Extraction ◽

Supported Liquid Membrane ◽

Distribution Data ◽

Membrane Phase ◽

Liquid Liquid Extraction ◽

Feed Phase ◽

Hcl Medium

Ionic liquid A327H+Cl− was generated by reaction of tertiary amine A327 and HCl, and the liquid-liquid extraction of indium(III) from the HCl medium by this ionic liquid dissolved in Solvesso 100 was investigated. The extraction reaction is exothermic. The numerical analysis of indium distribution data suggests the formation of A327H+InCl4− in the organic phase. The results derived from indium(III) extraction have been implemented in a supported liquid membrane system. The influence of the stirring speed (600–1200 min−1), carrier concentration (2.5–20% v/v) in the membrane phase, and indium concentration (0.01–0.2 g/L) in the feed phase on metal transport have been investigated.

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Modified TiO2Structures with Enhanced Photoluminescence and Photocatalytic Activity

Science of Advanced Materials ◽

10.1166/sam.2021.3896 ◽

2021 ◽

Vol 13 (2) ◽

pp. 331-341

Author(s):

Jinqi Wang ◽

Guopeng Li ◽

Wei Wang ◽

Fuxia Li ◽

Chuankai Yang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Rare Earth ◽

Photocatalytic Degradation ◽

Environmental Remediation ◽

Rare Earth Ions ◽

Shell Structures ◽

Rare Earth Complex ◽

Core Shell ◽

Rare Earth Ion ◽

The Rare Earth

Photocatalytic degradation of pollutants has attracted much attention because it can effectively solve the problem of environmental pollution. SiO2@Eu(TTA)3phen@TiO2 core-shell structures were successfully synthesized for the first time by a solvothermal method involving ultrasound assistance which can optimize the rare earth complex dispersibility and achieve strong emission intensity. SiO2@Eu3+@TiO2 core-shell structures were also successfully synthesized by a similar method. Photocatalytic activity analysis showed that the photocatalytic activity factor not only depended on the rare earth ion content, but also related to the structure and size of the TiO2 nanoparticles. Photocatalytic activity increased first and then decreased with the quantity of rare earth ions. Photocatalytic activity was also superior for hollow structures compared to solid structure. Photocatalytic activity of SiO2@TiO2 particles increased with the particle size, until the size increased to 450 nm. Rare earth ions content as well as particle structures and sizes affected efficiency for the photocatalytic degradation of methyl orange. Outstanding photocatalytic activity provides the composite particles with improved potential to purify aquatic contaminants and to meet the demands of future environmental remediation applications.

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Demulsification of Emulsion Liquid Membrane Extracting Rare Earth Ions in Leaching Liquid of Phosphate Rock

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.926-930.64 ◽

2014 ◽

Vol 926-930 ◽

pp. 64-67

Author(s):

Zi Nan Xie ◽

Qian Lin Chen

Keyword(s):

Rare Earth ◽

Phosphate Rock ◽

Liquid Membrane ◽

Inorganic Salt ◽

Sound Intensity ◽

Membrane System ◽

Rare Earth Ions ◽

Emulsion System ◽

Emulsion Liquid Membrane ◽

System A

This paper researched demulsification way for emulsion liquid membrane system extracting rare earth ions in leaching liquid of phosphate rock . Physical demulsification methods included heating, centrifugal, microwave. Chemical demulsification methods such as adding acid, alkal and inorganic salt were employed. The results showed that for Emulsion System A, the best way for demulsification was ultrasonic 30 min, 80 KHz sound intensity, 70°C ultrasonic temperature. The demulsification rate could reach 46% and concentration multiple of rare earth ions was 2 times. For Emulsion System B, centrifugal 90 min by 16000 r/min, the demulsification rate could reach the highest which was 52%, the concentration multiple of rare earth ions was 8 times.

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High Efficiency Light Emission Devices in Silicon

MRS Proceedings ◽

10.1557/proc-770-i2.1 ◽

2003 ◽

Vol 770 ◽

Cited By ~ 8

Author(s):

Maria E. Castagna ◽

Salvatore Coffa ◽

Mariantonietta Monaco ◽

Anna Muscara' ◽

Liliana Caristia ◽

...

Keyword(s):

Rare Earth ◽

Quantum Efficiency ◽

External Quantum Efficiency ◽

High Efficiency ◽

Gate Dielectric ◽

Chemical Vapour ◽

Rare Earth Ions ◽

Hot Electrons ◽

Light Emitting ◽

The Rare Earth

AbstractWe report on the fabrication and performances of the most efficient Si-based light sources. The devices consist of MOS structures with erbium (Er) implanted in the thin gate oxide. The devices exhibit strong 1.54 μm electroluminescence at 300K with a 10% external quantum efficiency, comparable to that of standard light emitting diodes using III-V semiconductors. Emission at different wavelenghts has been achieved incorporating different rare earths (Ce, Tb, Yb, Pr) in the gate dielectric. The external quantum efficiency depends on the rare earth ions incorporated and ranges from 10% (for an Tb doped MOS) to 0.1% (for an Yb doped MOS). RE excitation is caused by hot electrons impact and oxide wearout limits the reliability of the devices. Much more stable light emitting MOS devices have been fabricated using Er-doped SRO (Silicon Rich Oxide) films as gate dielectric. These devices show a high stability, with an external quantum efficiency reduced to 0.2%. In these devices Er pumping occurs part by hot electrons and part by energy transfer from the Si nanostructures to the rare earth ions, depending by Si excess in the film. Si/SiO2 Fabry-Perot microcavities have been fabricated to enhance the external quantum emission along the cavity axis and the spectral purity of emission from the films that are used as active media to realize a Si based RCLED (resonant cavity light emitting diode). These structures are realized by chemical vapour deposition on a silicon substrate. The microcavities are tuned at different wavelengths: 540nm, 980nm and 1540nm (characteristic emission wavelengths respectively for Tb, Yb and Er). The reflectivity of the microcavities is of 97% and the quality factor ranges from 60 (for the cavity tuned at 980nm) to 95 (for the cavities tuned at 540nm and 1540nm).

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Local symmetry and Z-scan analysis of ZnSe/Eu3+ doped sol–gel silica hosts

Canadian Journal of Physics ◽

10.1139/p10-030 ◽

2010 ◽

Vol 88 (7) ◽

pp. 493-500 ◽

Cited By ~ 1

Author(s):

Siby Mathew ◽

K. V. Arun Kumar ◽

C. Sudarsanakumar ◽

V. P.N. Nampoori ◽

N. V. Unnikrishnan

Keyword(s):

Rare Earth ◽

Sol Gel ◽

Glass Network ◽

Local Symmetry ◽

Wide Distribution ◽

Rare Earth Ions ◽

Saturable Absorption ◽

Rare Earth Ion ◽

Enhanced Absorption ◽

The Rare Earth

Vibrational state side-band spectral analysis of silica matrices, doped with ZnSe/Eu3+ ions, associated with the excitation transition 7F0→5D2 is used to analyze the local asymmetry of the rare earth ions in the glass host. The large inhomogeneous linewidth for the ZnSe co-doped samples indicates the wide distribution of the Eu3+ ions in the matrix and is related to the flexibility of the local glass network. The fluorescence spectra reveal that the intensity of the characteristic emission of europium increases considerably in the presence of ZnSe particles. This phenomenon can be explained by the energy transfer resulting from electron–hole recombination in the ZnSe to the rare earth ion. Nonlinear optical absorption of the sample is also investigated at a wavelength of 532 nm, using open aperture Z-scan technique. The sample exhibits reversible saturable absorption (RSA), which is found to depend on excitation fluence. RSA is due to the enhanced absorption resulting from the electron dynamics in nano-crystallites.

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Rare-Earth Doped Silicon-Rich Silica: Evidence for Energy Transfer between Silicon Microclusters and Rare-Earth Ions

MRS Proceedings ◽

10.1557/proc-358-117 ◽

1994 ◽

Vol 358 ◽

Cited By ~ 3

Author(s):

A.J. Kenyon ◽

P.F. Trwoga ◽

M. Federighi ◽

C.W. Pitt

Keyword(s):

Rare Earth ◽

Visible Region ◽

Rare Earth Ions ◽

Excitation Wavelength ◽

Rare Earth Ion ◽

Absorption Bands ◽

Strong Luminescence ◽

Doped Silicon ◽

Rare Earth Doped ◽

The Rare Earth

ABSTRACTWe report the fabrication of rare-earth doped silicon-rich silica thin films by PECVD. The films exhibit absorption edges in the visible region of the optical spectrum consistent with the presence of silicon microclusters. Weak visible photoluminescence due to silicon microclusters is observed. In addition, strong luminescence from the rare-earth ion is obtained even when excited away from characteristic absorption bands; indeed, the luminescence intensity is largely independent of excitation wavelength below 514 nm. We ascribe this to excitation of silicon microclusters followed by an efficient transfer of energy to the rare-earth ions.The very broad absorption of this material opens up the possibility for flashlamp-pumped optoelectronic devices. In addition, we report the fabrication of silicon-rich silica films by PECVD. We show that the optical properties of these films are consistent with the presence of silicon microclusters and show absorption spectra similar to those of the rare-earth doped silicon-rich silica samples. This supports the hypothesis that the principal absorbing species in the rare-earth doped films is microclustered silicon

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Uphill Transport of Rare-Earth Metals through a Highly Stable Supported Liquid Membrane Based on an Ionic Liquid

Analytical Sciences ◽

10.2116/analsci.26.289 ◽

2010 ◽

Vol 26 (3) ◽

pp. 289-290 ◽

Cited By ~ 44

Author(s):

Fukiko KUBOTA ◽

Yousuke SHIMOBORI ◽

Yusuke KOYANAGI ◽

Kojiro SHIMOJO ◽

Noriho KAMIYA ◽

...

Keyword(s):

Ionic Liquid ◽

Rare Earth ◽

Liquid Membrane ◽

Rare Earth Metals ◽

Supported Liquid Membrane

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Infrared and Electronic Spectra of Rare Earth Perovskites: Ortho-Chromites, -Manganites and -Ferrites

Applied Spectroscopy ◽

10.1366/000370270774371426 ◽

1970 ◽

Vol 24 (4) ◽

pp. 436-445 ◽

Cited By ~ 236

Author(s):

G. V. Subba Rao ◽

C. N. R. Rao ◽

J. R. Ferraro

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Transition Metal ◽

Ir Spectra ◽

Electronic Spectra ◽

Transition Metal Ions ◽

Rare Earth Ions ◽

Electronic Transitions ◽

Rare Earth Ion ◽

The Rare Earth

The electronic and ir spectra of rare earth perovskites of the general formula LnZO3, where Ln is the rare earth ion or yttrium and Z is Cr, Mn, or Fe, have been studied in detail. The results have been discussed in terms of crystallography, magnetic properties, covalency of Ln—O and Z—O bonds, and Goodenough's one electron energy diagrams. In all these compounds the rare earth ions do not markedly affect the electronic transitions of the transition metal ions; the 3 d electrons clearly exhibit localized behavior. Both the electronic and ir spectra of the LnZO3 perovskites are comparable to the spectra of the corresponding transition metal sesquioxides, Z2O3.

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