کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1405503 | 1501790 | 2012 | 7 صفحه PDF | دانلود رایگان |

Ultraviolet and visible spectroscopic studies of base undoped and V2O5-doped sodium silicophosphate glasses were carried out in order to characterize the valence states of vanadium ions in such host mixed glass forming oxides. The same spectroscopic measurements were repeated after subjecting the glass to gamma irradiation with a dose of 8 Mrad (8 × 104 Gy). The base glass without V2O5 reveals an UV absorption band which is related to the presence of unavoidable trace iron impurities within the chemicals used for the preparation of this glass. V2O5-doped glasses exhibit extended UV–visible absorption spectra which are attributed to the collective presence of vanadium ions in three possible valencies V3+, V4+ and V5+ with the lower valence predominating.Infrared absorption spectra of the prepared samples indicate the combined presence of vibrational bands due to the sharing of both phosphate and silicate networks in the IR spectra. The addition of V2O5 in the doping level (0.1–3%) did not cause obvious changes in the IR spectra. Gamma irradiation produces noticeable but limited UV–visible spectral variations which show some shielding behavior in some cases. X-ray diffraction technique was applied to confirm the amorphous nature of the prepared glasses. ESR spectral data confirm the optical spectra results indicating the presence of both V3+ and V4+ ions in measurable percent.
► Mixed glass former containing variable amounts of vanadium ions were prepared and studied.
► Deconvolution analysis technique (DAT) was performed to evaluate the role of each component.
► ESR was used to identify the valencies of the vanadium ions.
► Effects of gamma irradiation on optical absorption and structure of glasses were introduced.
► Vanadium ions reveal obvious retardation towards gamma irradiation.
Journal: Journal of Molecular Structure - Volume 1024, 26 September 2012, Pages 47–53