Interactions of gamma rays with tungsten-doped lead phosphate glasses

Abstract

Undoped lead phosphate glass of the composition PbO 50 mol%, P2O5 50 mol% together with samples of the same ratio doped with various WO3 contents were prepared. UV–Visible spectroscopic studies were measured out in the range 200–1100 nm before and after successive gamma irradiation. Infrared and Raman spectroscopic measurements were carried out for the undoped and WO3-doped samples. All the prepared samples are observed to absorb strongly in the UV region due to the combined contributions of absorption from trace iron impurities and sharing of lead Pb2+ ions. The bluish WO3-doped lead phosphate samples reveal visible absorption bands which are attributed to the existence of pentavalent W5+ ions. ESR measurements support this assumption. Infrared and Raman spectra indicate the presence of metaphosphate chains as the structural main building units and the possible presence of appreciable pentavalent (W5+O3) of W5+ units together with hexavalent WO4 units. Gamma irradiation reveal the shielding behaviour of the studied tungsten-doped lead phosphate glasses due to the combined presence of heavy Pb2+ ions and tungsten ions.