scholarly journals Effect of Rare-Earth Ions on the Optical and PL Properties of Novel Borosilicate Glass Developed from Agricultural Waste

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5607
Author(s):  
Aiyeshah Alhodaib ◽  
Omnia Ibrahim ◽  
Suzy Abd El All ◽  
Fatthy Ezzeldin
Keyword(s):  
Rare Earth ◽  
Agricultural Waste ◽  
Visible Spectrum ◽  
Rare Earth Oxides ◽  
Rare Earth Ions ◽  
Raw Material ◽  
Molar Ratio ◽  
Borosilicate Glasses ◽  
Excitation Spectra ◽  
Novel Structure

There is considerable attention devoted to the use of agricultural waste as a raw material substitute for commercial silica in the development of borosilicate glasses doped with rare earth oxides. Here, we present a novel structure for borosilicate glasses made from rice husk ash with a 25% molar ratio of extracted SiO2 and doped with neodymium (GRN) or dysprosium (GRD). Adding rare earth oxides to borosilicate glasses by the melt quenching method enhanced optical transmission due to the presence of their tetrahedral geometries. GRN samples showed few bands near zero, which constitutes good utility for band rejection filters in image devices, and the samples exhibited energy values ranging from 3.03 to 3.00 eV before and after gamma irradiation. Optical transmissions of GRD samples showed peaks at 25,974, 22,172, 13,333, 11,273, 9302, 7987, and 6042 cm−1. Deterioration in transmittance was observed when the investigated samples were exposed to irradiation doses of 20 and 50 kGy in the wavenumber range of 12,500 to 50,000 cm−1; however, different behaviors after irradiation with 50 kGy caused an increase in transparency in comparison to 20 kGy irradiation, which was pronounced for higher wavenumbers (greater than 12,500 cm−1). Photoluminescence emission and excitation spectra of the glass-doped Nd3+ (GRN) and glass-doped Dy3+ (GRD) samples were determined. GRD exhibited emission in the blue and yellow regions of the visible spectrum, which gave a white flash of light. Chromaticity coordinate (CIE) measurements of GRD samples indicated the origin of its luminous color relative to the standard white light region.

Saturation effects in the excitation spectra of rare-earth ions

1994 ◽  
Vol 62 (5) ◽  
pp. 189-201 ◽  
Author(s):  
C. de Mello Donegá ◽  
A. Meijerink ◽  
G. Blasse
Keyword(s):  
Rare Earth ◽  
Rare Earth Ions ◽  
Excitation Spectra ◽  
Saturation Effects

Persistence Mechanisms and Applications of Long Afterglow Phosphors

2015 ◽  
Vol 361 ◽  
pp. 69-94
Author(s):  
V. Shanker ◽  
D. Haranath ◽  
G. Swati
Keyword(s):  
Rare Earth ◽  
Visible Spectrum ◽  
Special Kind ◽  
Processing Parameters ◽  
Host Lattice ◽  
Rare Earth Ions ◽  
Energy Storage And Conversion ◽  
Slight Variation ◽  
Long Afterglow ◽  
Luminescence Efficiency

This article presents a broad review of long persistence (LP) materials that are a special kind of photon energy storage and conversion materials. They are also known as long afterglow phosphors or long decay phosphors (LDP). These phosphors can be readily excited by any ordinary household lamp, sunlight and/or ambient room lights and glow continuously in the dark for hours together without involving any radioactive elements. It is the modifications that are made to crystalline host lattice that exhibit these unusual properties related to persistence due to effective doping of some transition or rare-earth ions. A slight variation in the processing parameters such as type of reducing atmosphere, stoichiometric excess of one or more constituents, the nature of fluxes, and the intentional addition of carbon or rare-earth halides can drastically shift the emission colors and persistence times of the LP phosphors in the visible spectrum. Historically, Cu-doped ZnS phosphor had been a traditional LP material with its afterglow time less than an hour. The emission color of these LP phosphors was confined between green and yellow-green region only. However, synthesis of blue and red-emitting phosphors with long persistence times had been always a challenging task. This review article covers the recent advances in the blue, green and red-emitting LP phosphors/nanophosphors, persistence mechanism involved and the basic problems associated with their luminescence efficiency and persistence times. Modifications to existing nanosynthesis protocols to formulate a nontoxic Green Chemistry Route are also presented.Contents of Paper1. Long Afterglow Phosphors

scholarly journals Kinetics of luminescence calcium gallate activated by Yb3+, Er3+ ions

2020 ◽  
Vol 23 (3) ◽  
pp. 213-221
Author(s):  
A. P. Mar`in ◽  
U. A. Mar`ina ◽  
V. A. Vorob`ev ◽  
R. V. Pigulev
Keyword(s):  
Rare Earth ◽  
Luminescence Intensity ◽  
Luminescent Properties ◽  
Rare Earth Ions ◽  
Luminescence Spectra ◽  
Excitation Spectra ◽  
Semiconductor Laser Diode ◽  
Intracenter Luminescence ◽  
Trivalent Rare Earth ◽  
Kinetics Of

The paper presents the results of a study of the luminescent properties of calcium gallate activated by trivalent rare earth ions Yb3+ and Er3+. IR luminescence spectra of samples with a single activator Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4 were studied when excited by radiation sources with a wavelength of 940 and 790 nm, respectively. The dependence of the luminescence intensity of samples on the concentration of rare earth ions is obtained. When the two-activator composition of Ca1‑х‑yYbxEryGa2O4 is excited by a semiconductor laser diode with a wavelength of 940 nm, IR luminescence is registered in the regions of 980-1100 nm and 1450-1670 nm. The radiation in these bands corresponds to electronic transitions in Yb3+ and Er3+ ions, respectively. For a luminescence band with a maximum at a wavelength of 1540 nm, the excitation spectra were measured, the maximum intensity is at the wavelengths: 930, 941, 970, 980 nm. The dependence of the IR luminescence intensity of a solid solution of Ca1‑х‑yYbxEryGa2O4 on the concentration of Er3+ ions was studied. With an increase in the concentration of Er3+ ions in the luminescence spectra, there is a redistribution in the intensity of the bands belonging to Yb3+ and Er3+ ions, which indicates the presence of energy transfer processes between these ions. The kinetics of IR luminescence attenuation was studied for series with one and two activators: Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4, Ca1‑х‑yYbxEryGa2O4. It is established that the luminescence attenuation occurs mainly according to the exponential law, which indicates the predominance of the intracenter luminescence mechanism in the studied structures. Based on the analysis of the excitation and luminescence spectra of experimental samples, conclusions are made about the interaction of Yb3+ and Er3+ activator ions in the crystal lattice of calcium gallate.

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

2019 ◽  
Vol 20 (14) ◽  
pp. 3424
Author(s):  
Jianguo Li ◽  
Hongying Dong ◽  
Fan Yang ◽  
Liangcheng Sun ◽  
Zhigang Zhao ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Rare Earth ◽  
High Efficiency ◽  
Liquid Membrane ◽  
Membrane System ◽  
Rare Earth Ions ◽  
Raw Material ◽  
Supported Liquid Membrane ◽  
Rare Earth Ion ◽  
The Rare Earth

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+.

Study on Novel Structure of Glycolic and Oxalic Acid Holmium: [Ho (C3 H6O9)]·CH3OH

2012 ◽  
Vol 531-532 ◽  
pp. 417-420
Author(s):  
Hai Xing Liu ◽  
Wu Lan Zeng ◽  
Jing Zhong Xiao ◽  
Guang Zeng ◽  
Hui Juan Yue ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Rare Earth ◽  
Hydrothermal Reaction ◽  
Research Work ◽  
Functional Materials ◽  
Structural Diversity ◽  
Upconversion Emission ◽  
Rare Earth Ions ◽  
Rare Earth Doping ◽  
Novel Structure

In the study of functional materials, more attention is the construction of organic–inorganic hybrid materials with structural diversity, fascinating properties, and potential applications in catalysis, molecular adsorption, medicine, electro-conductivity, magnetism and photochemistry. At present, the research work in upconversion emission in rare-earth doping materials has been greatly increased. Yb3+ and Ho3+ upconversion energy transfer is attractive, because Yb3+ and Ho3+ upconversion energy transfer is relatively simple compared to upconversion involving other rare-earth ions. In this paper, a novel holmium complex [Ho (C3 H6O9)] •CH3OH has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Ho atom is coordinated by eight O atoms. The molecular is antisymmetric structure by the C2-C2 axis. The molecular structure stabilized by the O-H…O hydrogen-bonding interactions.

Optimization of host glass composition to make soda borosilicate glasses doped with reduced rare earth ions

2004 ◽  
Vol 223 (1-3) ◽  
pp. 238-240 ◽  
Author(s):  
Tomoya Konishi ◽  
Takehisa Matsumoto ◽  
Tetsuo Araki ◽  
Toshio Tsuchiya ◽  
Shin-ichi Todoroki ◽  
...  
Keyword(s):  
Rare Earth ◽  
Glass Composition ◽  
Rare Earth Ions ◽  
Borosilicate Glasses ◽  
Host Glass

Diffuse-Reflectance Spectra of Rare-Earth Oxides

1967 ◽  
Vol 21 (3) ◽  
pp. 167-171 ◽  
Author(s):  
William B. White
Keyword(s):  
Rare Earth ◽  
Diffuse Reflectance ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Rare Earth Oxides ◽  
Rare Earth Ions ◽  
Reflectance Spectra ◽  
Solid Materials ◽  
Diffuse Reflectance Spectra ◽  
Structural Types

Diffuse-reflectance spectra are reported for 11 rare-earth oxides of various structural types over the spectral range of 225–2700 mμ. These spectra, particularly in the near infrared, permit the use of diffuse-reflectance spectroscopy to identify rare-earth ions in solid materials.

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