Optical and shielding behavior studies of vanadium-doped lead borate glasses

A glass sample of composition PbO 42.1%– B₂O₃ 57.9 mol% B₂O₃ together with samples of the same composition doped with varying V₂O₅ contents was prepared via melt annealing technique. X-ray diffraction technique was applied to prove the amorphous nature of the prepared glasses. UV–visible absorption spectra were measured in the range 200–1500 nm before and after successive gamma irradiation, which were applied to evaluate optical properties, including direct and indirect optical energy band gaps before and after gamma irradiation. Undoped glass sample is observed to exhibit strong UV absorption; due to the combined contributions of absorption of both Pb²⁺ ions and trace iron impurities. The presence of V³⁺ ions together with the other vanadium valence states (V⁴⁺, V⁵⁺) was proved by the appearance of extra visible absorption bands. Infrared absorption spectra were measured in the range 4000–400 cm⁻¹ which revealed the presence of both triangular and tetrahedral borate groups besides the sharing of lead ions.