Induced defects by gamma irradiation doses on the structure and optical behavior of undoped and TiO2-, Cr2O3-, or MnO-doped heavy metal borate glasses

Abstract

A series of un-doped and TiO2-, Cr2O3- or MnO-doped heavy metal borate glasses were prepared by the conventional melt annealing method. The prepared glasses were examined via optical absorption measurements in the UV–visible region. The optical absorption spectra before and after gamma irradiation show a fixed characteristic peak in the UV region with other extended peaks in the visible region caused by the addition of the selected transition metal ions; Ti4+, Cr3+, or Mn2+. The obtained optical band gap values reveal an observed decrease as a result of both the addition of such transition metal ions and the effect of increasing the dose of gamma radiation. Infrared absorption spectra (FTIR) were applied to identify the environmental structure of the prepared glasses before and after different doses of gamma radiation. Results of IR spectra show that both BO3 and BO4 are the basic building units, in addition to PbO4 units. Electron spin resonance (ESR) and some of glasses physical parameters like density, oxygen packing density, molar and specific volumes were also investigated and revealed the good stability of the prepared glasses towards different doses of gamma radiation because of the high content of heavy metal Pb2+ ions.