Luminescence in Rare Earth Activated AlPO4 Phosphor

2011 ◽  
Vol 306-307 ◽  
pp. 171-175 ◽  
Author(s):  
K.N. Shinde ◽  
S.J. Dhoble

Rare earth activated AlPO4 phosphors were synthesized by solid-state reactions and the completion of the synthesis was confirmed by X-ray diffraction (XRD) pattern. Under near-ultraviolet (nUV) light, the Eu3+ emission in AlPO4 consists of the transitions from 5D0 to 7FJ shows orange/red region and the AlPO4 :Dy3+ phosphor shows an efficient blue and yellow band emissions, which originates from the 4F9/26H15/2 and 4F9/26H13/2 transitions of Dy3+ ion. The excitation spectra of the phosphors are extending from 300 to 400 nm, which are characteristics of nUV excited LED. The effect of the Eu3+ and Dy3+ concentration on the luminescence properties of AlPO4 phosphors is also studied.

2015 ◽  
Vol 73 (1) ◽  
Author(s):  
Nur Zu Ira Bohari ◽  
R. Hussin ◽  
Zuhairi Ibrahim ◽  
Hendrik O. Lintang

Glass has been widely utilized in the field of lighting, telecommunication and spectroscopy. Boro-tellurite is one of the suitable glasses used for solid state lighting and laser application. The investigation on the luminescence properties of rare earth doped ceramic is rarely used due to the opacity. In this paper boro-tellurite prepared in ceramic can show the better luminescence with the less advantage. The aim of this paper is to present the effect and advantages in luminescence results of boro-tellurite ceramics doped with the constant amount of rare earth. Doped magnesium boro-tellurite with Eu3+ and Dy3+ ceramic have been prepared using solid state reaction method with the compositions of xTeO2-(70-x)B2O3-30MgO with 10≤x≤40, and have been doped with Eu2O3 (1mol%) and Dy2O3 (1mol%) . The characterizations of the samples have been investigated by means of X-Ray diffraction, Raman, Infrared and Photoluminescence spectroscopy. From the X-ray diffraction results, two phases are assigned to MgTe2O5 and Mg2B2O5. Raman spectroscopy showed strong bands observed in the vicinity of 140, 175, 220, 266, 332, 403, 436, 646, 694, 723, 757 and 806 cm-1. FTIR spectra showed bands located in the range between 400-800 cm-1 are assigned to the bending mode of Te-O-Te, TeO3 and TeO4. In the range of 800-1400 cm-1,the bands are associated with B-O, B-O-B, BO3 and BO4 bonds. The emission transition 5D0-7F2 corresponded to the red emission (612 nm) was found to be the most intense in all the Eu3+-doped magnesium boro-tellurite ceramics.  


2017 ◽  
Vol 58 (1) ◽  
Author(s):  
Rodrigo Castañeda ◽  
Elizabeth Chavira ◽  
Oscar Peralta

<p>Thermal analyses, X-ray diffraction (XRD), and HR-XRD (High Resolution XRD) were used to identify thermal behavior products in a family of solid-state reactions involving rare earth (REE) reagents. REE where sorted in light and heavy groups. The general reactions under study were: REE<sub>2</sub>O<sub>3</sub> + Fe<sub>2</sub>O<sub>3</sub> + As<sub>2</sub>O<sub>3</sub> → 2REEFeO<sub>3</sub> +<br />As<sub>2</sub>O<sub>3</sub>↑ and 2REE(OH)<sub>3</sub> + Fe<sub>2</sub>O<sub>3</sub> + As<sub>2</sub>O<sub>3</sub> → 2REEFeO<sub>3</sub> + As<sub>2</sub>O<sub>3</sub>↑ + 3H<sub>2</sub>O↑, REE= La, Ce, Nd, Sm, Gd, Dy, Ho, Er, and Yb. Based on the experimental results, it is possible to predict the different compounds of REE products in a series of reactions analyzing only three of the reactions, two for light REE and one for heavy REE.</p>


Author(s):  
F. Ma ◽  
S. Vivekanand ◽  
K. Barmak ◽  
C. Michaelsen

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.


1994 ◽  
Vol 9 (3) ◽  
pp. 648-657 ◽  
Author(s):  
J.S. Chen ◽  
E. Kolawa ◽  
M-A. Nicolet ◽  
R.P. Ruiz ◽  
L. Baud ◽  
...  

Thermally induced solid-state reactions between a 70 nm Pt film and a single-crystal (001) β-SiC substrate at temperatures from 300 °C to 1000 °C for various time durations are investigated by 2 MeV He backscattering spectrometry, x-ray diffraction, secondary ion mass spectrometry, scanning electron microscopy, and cross-sectional transmission electron microscopy. Backscattering spectrometry shows that Pt reacts with SiC at 500 °C. The product phase identified by x-ray diffraction is Pt3Si. At 600–900 °C, the main reaction product is Pt2Si, but the depth distribution of the Pt atoms changes with annealing temperature. When the sample is annealed at 1000 °C, the surface morphology deteriorates with the formation of some dendrite-like hillocks; both Pt2Si and PtSi are detected by x-ray diffraction. Samples annealed at 500–900 °C have a double-layer structure with a silicide surface layer and a carbon-silicide mixed layer below in contact with the substrate. The SiC—Pt interaction is resolved at an atomic scale with high-resolution electron microscopy. It is found that the grains of the sputtered Pt film first align themselves preferentially along an orientation of {111}Pt//{001}SiC without reaction between Pt and SiC. A thin amorphous interlayer then forms at 400 °C. At 450 °C, a new crystalline phase nucleates discretely at the Pt-interlayer interface and projects into or across the amorphous interlayer toward the SiC, while the undisturbed amorphous interlayer between the newly formed crystallites maintains its thickness. These nuclei grow extensively down into the substrate region at 500 °C, and the rest of the Pt film is converted to Pt3Si. Comparison between the thermal reaction of SiC-Pt and that of Si–Pt is discussed.


1983 ◽  
Vol 93 (2) ◽  
pp. 433-440 ◽  
Author(s):  
M. Kizilyalli ◽  
D.S. Jones ◽  
N. Evi̇n ◽  
H. Göktürk

2011 ◽  
Vol 66 (5) ◽  
pp. 549-552
Author(s):  
Yan Bai ◽  
Guo Qiang Zhang ◽  
Dong Bin Dang ◽  
Ze Yan Qi ◽  
Li Zhang

The title compound [FTMA]2[CdI4] has been synthesized from [FTMA]I (ferrocenylmethyltrimethylammonium iodide) and 3CdSO4・8H2O and was characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The Cd(II) atom has a slightly distorted tetrahedral coordination sphere. In the solid state there are C-H・ ・ ・π interactions between adjacent ferrocenyl cations to generate a chain structure. The luminescence properties of the title compound were investigated in the solid state at room temperature


2001 ◽  
Vol 34 (5) ◽  
pp. 677-678 ◽  
Author(s):  
Anna Puig-Molina ◽  
Bernard Gorges ◽  
Heinz Graafsma

A furnace covering the temperature range from 25 to 1000°C has been designed and constructed to studyin situsolid-state reactions and melting and crystallization processes, with X-ray diffraction in transmission geometry using a two-dimensional-detector system. The oven can work in low vacuum and under a controlled atmosphere.


2010 ◽  
Vol 13 (1-2) ◽  
pp. 17
Author(s):  
K.V.R. Murthy ◽  
K. Suresh ◽  
B. Nageswara Rao ◽  
B. Walter Ratna Kumar ◽  
Ch. Atchyutha Rao ◽  
...  

<p>The present paper reports the Photoluminescence (PL) of the Sr<sub>2</sub>CeO<sub>4</sub> phosphor, singly doped with Erbium rare-earth ion with different concentrations (0.01, 0.1, 0.2, 0.5 and 1%).The phosphor samples were synthesized using the standard solid state reaction technique. The effect of Er dopant on the structural, morphological, and Photoluminescent properties of the samples are studied with X-ray diffraction (XRD), PL and SEM analysis. The PL emission of undoped Sr<sub>2</sub>CeO<sub>4</sub> phosphor was observed at 470 nm with high intensity followed by the primary Er emissions with good intensity at 525, 530, 549, 557 and 565 nm.</p>


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