Effects of Gamma Irradiation on Optical Properties of Colloidal Nanocrystals

2007 ◽  
Vol 1038 ◽  
Author(s):  
Nathan J Withers ◽  
Krishnaprasad Sankar ◽  
Brian A. Akins ◽  
Tosifa A. Memon ◽  
Jiangjiang Gu ◽  
...  

AbstractThe effects of 137Cs gamma irradiation on photoluminescence properties, such as spectra, light output, and lifetime, of several types of colloidal nanocrystals have been investigated. Irradiation-induced damage testing was performed on CdSe/ZnS, LaF3:Eu, LaF3:Ce, ZnO, and PbI2 nanocrystals synthesized on a Schlenk line using appropriate solvents and precursors. Optical degradation of the nanocrystals was evaluated based on the measured dependence of their photoluminescence intensity on the irradiation dose. Radiation hardness varies significantly between various nanocrystalline material systems.

2019 ◽  
Vol 127 (9) ◽  
pp. 420
Author(s):  
Р.М. Сардарлы ◽  
Ф.Т. Салманов ◽  
Н.А. Алиева

The effect of gamma irradiation on the optical properties of layered TlGaSe2 and TlInS2 crystals in the wavelength range of 400–1,100 nm at 300 K is studied. From the analysis of optical absorption spectra, the energies of direct and indirect optical interband transitions before and after gamma irradiation are determined. It is shown that as the gamma-irradiation dose is accumulated in the range of 0–25 Mrad by TlGaSe2 and TlInS2 single crystals, the energies of direct and indirect allowed optical transitions increase from Egd = 2.06 eV and Egi = 1.90 eV at D = 0 Mrad to Egd = 2.11 eV and Egi = 1.98 eV at D = 25 Mrad for TlGaSe2 and Egd = 2.32 eV crystals and Egi = 2.27 eV at D = 0 Mrad to Egd = 2.35 and Egi = 2.32 eV at D = 25 Mrad for TlInS2 crystals. A decrease in the transmittance at doses from 0 to 5 Mrad and a further increase in the transmittance at the radiation dose D = 25 Mrad are observed.


2016 ◽  
Vol 48 (4) ◽  
Author(s):  
Svetlana Jovanović ◽  
Zoran Marković ◽  
Milica Budimir ◽  
Zdenko Spitalsky ◽  
Bojan Vidoeski ◽  
...  

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ali A. Alhazime ◽  
Nesreen T. El-Shamy ◽  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh

AbstractNanocomposite films of polymethylmethacrylate PMMA with Sn0.75Fe0.25S2 nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Changes in PMMA/Sn0.75Fe0.25S2 nanocomposite (NCP) due to gamma irradiation have been measured. XRD results indicate that the gamma doses of 10–80 kGy cause intermolecular crosslinking that reduces the ordered portion in the NPs. Bonding between the NPs and the host PMMA was confirmed by FTIR. TGA results indicate an enhancement in thermal stability in the NCP films irradiated with doses 20–80 kGy. The optical band gap was reduced from 3.23 to 2.47 eV upon gamma irradiation up to 80 kGy due bonding between the NPs and PMMA which enhanced the amorphous part of the NPs. Finally, the color variation between the blank and irradiated films (ΔE) was determined. Color changes immensely when the PMMA/Sn0.75Fe0.25S2 NCP films are gamma irradiated. Values of ΔE were as much as 31.6 which is an acceptable match in commercial reproduction on printing presses.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ateyyah M. Al-Baradi ◽  
Ahmed A. Atta ◽  
Ali Badawi ◽  
Saud A. Algarni ◽  
Abdulraheem S. A. Almalki ◽  
...  

Abstract In the current work, the optical properties of tin oxide thin films have been tailored via gamma irradiation for energy applications. The effect of Gamma radiation (50, 100, 150, 200 and 250 kGy) on the microstructural, absorption and oscillator parameters of SnO2 thin films has been investigated. XRD results reveal that the SnO2 films have the symmetry of the space group P42/mnm belonging to the tetragonal system. The crystallite size of γ-irradiated SnO2 thin film slightly increases as the irradiation dose increases. The allowed optical band gaps are estimated by applying various methods such as Tauc’s method, derivation of absorption spectrum fitting and absorption spectrum fitting approaches. The dispersion parameters are extracted from the dispersion curve of the real part of the refractive index. The single-effective-oscillator and Drude models for free charge carrier absorption are applied to obtain the dispersion parameters before and after γ-irradiation.


2021 ◽  
Vol 127 (10) ◽  
Author(s):  
M. I. A. Abdel Maksoud ◽  
Soraya Abdelhaleem ◽  
Eman K. Tawfik ◽  
Ahmed G. Bedir ◽  
Asmaa S. Morshedy

Silicon ◽  
2018 ◽  
Vol 11 (5) ◽  
pp. 2499-2504 ◽  
Author(s):  
M. N. Mirzayev ◽  
S. H. Jabarov ◽  
E. B. Asgerov ◽  
R. N. Mehdiyeva ◽  
T. T. Thabethe ◽  
...  

1994 ◽  
Vol 348 ◽  
Author(s):  
N.V. Kilassen

ABSTRACTThe studies of the dependence of the optical properties of various scintillators on intrinsic structural defects have been reviewed. The greater part of the review is devoted to the defects introduced by plastic deformation. A wide range of variations in the light output, spectral distribution, kinetics and other properties has been observed. These defects can be induced during crystal growth, annealing, processing, etc. The proper regulation of the superstructure of intrinsic defects can ensure the production of high quality scintillators having required properties.


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