Cadmium Borate Glass as Host Media for Nickel Oxide Dopant

Nickel-doped cadmium borate glasses of various nickel oxide contents were prepared. UV-visible, and IR spectra of the prepared glasses were studied before and after exposure to gamma ray 8MR dose. Experimental optical data for the undoped glass reveal strong UV absorption originating from contaminated trace iron mainly (Fe3+) impurities present in the chemicals used for the preparation of this glass. NiO-doped glasses show characteristic absorption bands due mainly to octahedral coordination of divalent nickel (Ni2+) ions. Gamma irradiation produces induced bands generated from intrinsic defects from the undoped glass and extrinsic defects from collective sharing of trace iron impurities and nickel ions through possible photochemical processes. The changes in the spectroscopic data are discussed in relation to the state of nickel ions in this host glass. FTIR absorption spectra reveal combined presence of triangular and tetrahedral borate units in their specific wavenumbers. The effects of both NiO and gamma irradiation on the IR spectra were evaluated by the consideration of the shielding effect of the host base glass containing high content of heavy metal oxide (CdO)and the presence of low dopant ions which are situated in interstitial positions.