X-ray photoelectron spectroscopy (XPS) and radiation shielding parameters investigations for zinc molybdenum borotellurite glasses containing different network modifiers

• Published in: Journal of materials science Vol. 52; no. 12; pp. 7394 - 7414
• Main Authors: Lakshminarayana, G., Baki, S. O., Lira, A., Sayyed, M. I., Kityk, I. V., Halimah, M. K., Mahdi, M. A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-06-2017; Springer; Springer Nature B.V
• Subjects: Alkali metals; Analysis; Atomic properties; Attenuation coefficients; Bonding; Boron oxides; Calcium; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Configurations; Crystallography and Scattering Methods; Fast neutrons; Glass; Heavy metals; Investigations; Lithium oxides; Magnesium; Materials Science; Mathematical analysis; Mean free path; Molybdenum; Molybdenum oxides; Molybdenum trioxide; Original Paper; Oxygen atoms; Parameter modification; Photoelectrons; Photons; Polymer Sciences; Radiation (Physics); Radiation shielding; Software; Solid Mechanics; Spectra; Spectrum analysis; X ray photoelectron spectroscopy; X-ray spectroscopy; Zinc; Zinc compounds; Incident Photon Energy; MoO3; TeO2; Mean Free Path; Tellurite Glass
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-017-0974-0

Zinc molybdenum borotellurite glasses containing different network modifiers with the nominal composition of 60 TeO
2
–10 B
2
O
3
–10 MoO
3
–10 ZnO–10 MO (MO = Li
2
O, Na
2
O, K
2
O, MgO, CaO, and PbO) were prepared by melt quenching method. The X-ray photoelectron spectroscopy (XPS) studies allow to monitor the structural modifications leading to the formation of bridging oxygens (Te–O–Te, B–O–B, Mo–O–Mo, and Te–O–Mo bonds) and nonbridging oxygens (Te = O, Te–O
−
M
+
, Mo–O
−
bonds in the MoO
6
octahedral units, Zn–O bonds from ZnO
4
) with the addition of alkali (Li, Na, and K), alkaline (Mg, Ca), or heavy metal (Pb) oxides. The Te 3d localized core-levels spectra show an asymmetry due to the existence of different Te-based structural clusters and were fitted with three contributions such as Te ions in TeO
4
trigonal bipyramid configuration, Te ions in TeO
3
−
trigonal pyramid configuration and TeO
3+1
polyhedra, respectively. The analysis of the Mo 3d spectra indicates prevailingly Mo
6+
ions only. The Zn 2p core-level XPS spectra demonstrate that the zinc is mainly coordinated by four oxygen atoms. The essential radiation shielding parameters were studied for the prepared glasses in the photon energy range 1 keV to 100 GeV using WinXCom software program. Parameters like mass attenuation coefficient (
μ/ρ
), effective atomic number (
Z
eff
), and mean free path (MFP) are evaluated. Further, by using geometric progression method, exposure buildup factor (EBF) values were also calculated in the incident photon energy range 0.015–15 MeV, up to penetration depth of 40 mfp (mean free path). The macroscopic effective removal cross sections (∑
R
) for fast neutrons have been calculated. The maximum values of μ/ρ and
Z
eff
were found for PbO-introduced glass though it possesses a lower value for MFP and EBF. The obtained results indicate that PbO-based glass is the best radiation shielding material among the studied glasses.