Ta(2)O(5) Nanocrystals Strengthened Mechanical, Magnetic, and Radiation Shielding Properties of Heavy Metal Oxide Glass.

In this study, for the first time, diamagnetic 5d(0) Ta(5+) ions and Ta(2)O(5) nanocrystals were utilized to enhance the structural, mechanical, magnetic, and radiation shielding of heavy metal oxide glasses. Transparent Ta(2)O(5) nanocrystal-doped heavy metal oxide glasses were obtained, and the embedded Ta(2)O(5) nanocrystals had sizes ranging from 20 to 30 nm. The structural analysis of the Ta(2)O(5) nanocrystal displays the transformation from hexagonal to orthorhombic Ta(2)O(5). Structures of doped glasses were studied through X-ray diffraction and infrared and Raman spectra, which reveal that Ta(2)O(5) exists in highly doped glass as TaO(6) octahedral units, acting as a network modifier. Ta(5+) ions strengthened the network connectivity of 1-5% Ta(2)O(5)-doped glasses, but Ta(5+) acted as a network modifier in a 10% doped sample and changed the frame coordination units of the glass. All Ta(2)O(5)-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 cm(2)/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 Ta(2)O(5) nanocrystals.