| The effects of gamma irradiation in the dose rate of 25 kGy on the structural
and optical properties of ZrO2 doped sodium borate glasses were studied.
Glassy nature confirmed by XRD and all the physical parameters were calculated.
IR spectra revealed the characteristic vibrational and stretching bands due to
trigonal and tetrahedral borate network. Slight changes were caused by gamma
irradiation in the intensities of the characteristic infrared borate bands and
zirconium bands. Irradiated samples developed a noticeable absorption band
similar to the F-band familiar in alkali halide crystals which clearly indicated that
successive irradiation produced defects in the glass material. Substitution of
ZrO2 to the glass matrix suppressed the formation of visible absorption band
formed by irradiation whereas no extra peak was observed in the spectral
regions. A nonlinear trend was ascribed in the energy band gap values due to
the creation of more number of non-bridging oxygen atoms. Emission spectra
showed five emission bands corresponding to the zirconium ions which
decreased to a very low intensity with a red shift after irradiation. Matching the
colour co-ordinates bright blue emission was found for 5 mol% ZrO2 in both
irradiated and non irradiated sample.
[Keywords: Zirconium oxide, Gamma irradiation, Red energy shift, Non-bridging
oxygens, Blue emission] |
