UV-visible and infrared absorption spectra of gamma irradiated V2O5-doped in sodium phosphate, lead phosphate, zinc phosphate glasses: A comparative study

Radiation-induced defects generated by successive gamma irradiation have been investigated in V2O5-doped phosphate glasses of three basic compositions, namely, sodium metaphosphate, lead metaphosphate and zinc metaphosphate. Glasses were prepared from chemically pure materials. Melting was carried at 900 degree -1100 degree C for 1h and with several stirrings of the melt to achieve homogeneity. The glassy samples were annealed at 200 degree -250 degree C and left to cool to room temperature at a rate of 20 degree C/h. Polished samples from undoped and V-doped samples of equal thickness. similar to 2mm were measured in a double beam UV-visible spectrophotometer at 200-1000nm before and after gamma irradiation. Induced defects were analyzed for these three phosphate glass systems. Infrared absorption spectra were measured for the prepared undoped and V-doped samples by the KBr technique before irradiation and after being subjected to a high dose of 7M Rads (7A-104 Gy). The cumulative effects of gamma irradiation on the UV-visible spectra are correlated with the intrinsic and extrinsic defects within the various three glasses. Some shielding behavior for the various glasses towards successive gamma irradiation are observed and realized in relation to the different partner anions studied. The effect of gamma irradiation on IR spectra indicates the persistence of the main characteristic bands due to phosphate network and the minor changes are correlated with the possible changes in the bond lengths and/or bond angles of the building units during the irradiation process. The effect of V2O5 on the IR spectra is correlated with the depolymerization effect of the glass network.