Gamma rays interactions with WO3-doped lead borate glasses

Optical and FT infrared spectral properties of tungsten ions in a host lead borate glass with composition PbO 55%, B2O3 45% (wt%) were studied. The same spectral properties were re-measured after subjecting the samples to successive gamma irradiation. The work was undertaken to justify the state of tungsten ions in such glass system by combined spectral investigations. Optical and FTIR spectral studies were confirmed by investigating electron spin resonance (ESR) of the undoped and WO3-doped samples before and after gamma irradiation. The optical spectrum of the undoped glass exhibits strong and wide UV absorption bands, which are related to the combined UV spectra of trace iron impurities (Fe3+ ions) and that from divalent lead (Pb2+) ions. Optical studies of WO3-doped sample indicate the presence of tungsten ions mostly in the hexavalent W6+ state. The presence of tungsten ions as structural groups was obtained by comparing the FTIR spectra of the undoped and WO3-doped samples. ESR spectra confirm the optical and FTIR spectral studies. The studied host lead borate glass has been found to show obvious shielding behavior towards successive gamma irradiation as revealed by the constancy of optical absorption spectral curves.