Ta2O5 Nanocrystals Strengthened Mechanical, Magnetic, and Radiation Shielding Properties of Heavy Metal Oxide Glass

Abstract

In this study, for the first time, diamagnetic 5d⁰ Ta⁵⁺ ions and Ta₂O₅ nanocrystals were utilized to enhance the structural, mechanical, magnetic, and radiation shielding of heavy metal oxide glasses. Transparent Ta₂O₅ nanocrystal-doped heavy metal oxide glasses were obtained, and the embedded Ta₂O₅ nanocrystals had sizes ranging from 20 to 30 nm. The structural analysis of the Ta₂O₅ nanocrystal displays the transformation from hexagonal to orthorhombic Ta₂O₅. Structures of doped glasses were studied through X-ray diffraction and infrared and Raman spectra, which reveal that Ta₂O₅ exists in highly doped glass as TaO₆ octahedral units, acting as a network modifier. Ta⁵⁺ ions strengthened the network connectivity of 1-5% Ta₂O₅-doped glasses, but Ta⁵⁺ acted as a network modifier in a 10% doped sample and changed the frame coordination units of the glass. All Ta₂O₅-doped glasses exhibited improved Vicker's hardness, magnetization (9.53 × 10^-6 emu/mol), and radiation shielding behaviors (RPE% = 96-98.8%, MAC = 32.012 cm²/g, MFP = 5.02 cm, HVL = 0.0035-3.322 cm, and Z_eff = 30.5) due to the increase in density and polarizability of the Ta₂O₅ nanocrystals.

Keywords: Ta2O5; heavy metal oxide glass; mechanical property; radiation shielding.

Figure 1

Schematic diagram with simulation geometry of the radiation shielding measurement.

Figure 2

XRD patterns (a-c) and deconvolution of Raman spectra (d-f) of Ta₂O₅ prepared at 600 °C, 800 °C and 1000 °C, respectively.

Figure 3

TME images of PBT₁ (a), PBT₅ (b), and PBT₁₀ (c) and their photographs, the insets are nanocrystal distribution inside glasses.

Figure 4

XRD pattern (a), FT-IR spectra (b), Raman (c), and Raman deconvolution (of PBT₁₀) (d) of three samples.

Figure 5

XPS core level energy outline (a) of B1s (b) and O1s (c) of the PBT₁, PBT₅, and PBT₁₀ glasses, respectively.

Figure 6

Composition dependence of bridging oxygen numbers, Vickers hardness (a) and density, OPD, and optical basicity (b) of glasses.

Figure 7

Vickers hardness indentations on the host (a), 467.98 HV, PBT₁ (b), PBT₅ (c), and PBT₁₀ (d).

Figure 8

Variation of the MAC (a) and CS cross-section (b) of the fabricated glasses versus the gamma ray energy. Curves in (b) are polynomial fitting of the data (blue: y = 41.9813 − 0.016x + 4.23 × 10⁻⁶ x²; red: y = 23.019 − 0.006x + 4.17 × 10⁻⁶ x²; black: y = 12.309 − 0.007x + 5.02 × 10⁻⁶ x².

Figure 9

The mean free path (MFP) of glasses at different incident gamma ray energy.

Figure 10

Z_eff (a), HVL (b), and RPE% (c) of three samples as functions of radiation energy. The green curves in (c) are guides.

Figure 11

M-H loop of nanocrystals Ta₂O₅ (a) and Ta₂O₅-doped glasses (b) at room temperature.