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Impact of Co-doping Eu3+ and Gd3+ in HMO-Based Glasses for Structural and Optical Properties and Radiation Shielding
Ashwitha Nancy D'Souza1,2, Sumanth G Madivala3, A Vidya Saraswathi1
1Department of Physics, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, India.
Abstract:
Eu-Gd co-doped glasses composed of 15B2O3-12SiO2-(40-x)TeO2-3Eu2O3-xGd2O3-12Bi2O3-8BaO-10ZnO with x = 0-4 mol% (coded as EuGd-x) were fabricated using melt quench approach to develop transparent radiation shielding system. Their structural, optical and mechanical properties were examined. 5.3663, 5.4264, 5.7405, 5.4683 and 5.6756 g/cm3 were the densities of EuGd-0, EuGd-1, EuGd-2, EuGd-3 and EuGd-4, respectively. Gamma shielding ability of EuGd system was simulated using the Photon Shielding and Dosimetry software in energy spectrum 0.015-15 MeV. On co-doping Gd3+ with Eu3+, clear advancement in gamma and neutron shielding ability was perceived; EuGd-2 dominates because of the highest density. At 0.662 MeV, the uppermost and lowermost (0.501 and 0.468 cm-1) linear attenuation coefficients (LAC) were demonstrated by EuGd-2 and EuGd-0, respectively. EuGd-2 distinguished itself with least half value layer (HVL) = 1.383 cm at 0.662 MeV, compared to EuGd-0 (1.483 cm). Photon build-up inside the glasses declined with Gd concentration at low gamma energies (< 2 MeV). EuGd-2 also showcased maximum fast neutron removal (FNR) cross-sectional value (0.10935 cm-1). Comparison between singly doped Eu2O3, Gd2O3 glasses and the current co-doped glasses established that EuGd-2 is the superior gamma shield in terms of LAC, HVL and effective atomic number.
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