Investigation of thermoluminescence characteristics of CaSrS: Ce nanophosphors

• Published in: Physica. B, Condensed matter Vol. 405; no. 21; pp. 4526 - 4529
• Main Authors: Sharma, Geeta, Lochab, S.P., Singh, Nafa
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01-11-2010; Elsevier
• Subjects: Condensed matter; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Glow curves; Mathematical analysis; Mixed lattice; Nanocomposites; Nanocrystals and nanoparticles; Nanomaterials; Nanoparticles; Nanophosphors; Nanostructure; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Thermoluminescence; Mixed lattice; Nanophosphors; Thermoluminescence; Radiation effects; Cubic lattices; Doping; XRD; High temperature; Nanoparticles; Ultraviolet radiation; Transmission electron microscopy; Cerium additions; Kinetics; Activation energy; Calcium Strontium Sulfides Mixed
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2010.08.031

Thermoluminescence characteristics of Ca
0.75Sr
0.25S: Ce nanophosphors exposed to UV radiations have been investigated. Solid state diffusion method was employed to synthesize the nanophosphors. The confirmation for the formation of the mixed lattice was done by XRD. The particles formed were found to have 45
nm size as calculated by the Debye Scherrer formula. TEM results were in close agreement with the XRD as the nanoparticles formed possess capsule like structure with an average diameter of 50
nm. TL glow curves for the low doses (110–1680
mJ/cm
2) of UV show a main peak around 381
K and another peak of very low intensity around 570
K. The TL intensity increases up to 450
mJ/cm
2 of UV exposure. At higher doses (3.5–80
J/cm
2) the peak position varies slightly but the high temperature peak becomes more intense. Thermoluminescence characteristics of UV irradiated Ca
1−
x
Sr
x
S: Ce as a function of
x (0.25, 0.50, and 0.75) have also been investigated. TL glow curves of Ca
1−
x
Sr
x
S: Ce (0.25, 0.50, and 0.75) recorded after 450
mJ/cm
2 of exposure of UV radiations show almost similar structure except slight variation in the peak position. Ca
0.25Sr
0.75S: Ce and Ca
0.50Sr
0.50S: Ce have single peak at 373 and 367
K, respectively, while Ca
0.75Sr
0.25S: Ce has a main peak at 381
K and a less intense peak at 570
K. Ca
0.75Sr
0.25S: Ce shows the most intense TL peak. The trap parameters namely, activation energy (
E), order of kinetics (
b), and frequency factor (
s) of Ca
0.75Sr
0.25S: Ce have been determined using Chen’s peak shape method and GCD function suggested by Kitis for second order kinetics.