Structural and optical absorption studies on Cr2O3 doped SrO-P2O5 glasses.

ABSTRACT

Cr2O3 doped glasses in the system xCr2O3-(60-x) P2O5-40SrO, where x = 0.0, 0.025, 0.05, 0.1, 0.2, 0.4 & 0.6 mol% were prepared and investigated by X-ray, UV-Vis, and FT infrared spectroscopy. According to the X-ray data, no sharp peaks can be observed, but only abroad halo which points the amorphous nature of the glass samples. Optical absorptions have shown that Cr ions are present in two possible oxidation states (trivalent & hexavalent). Increasing Cr2O3 concentrations in the glass network cause a reduction in the indirect and direct optical energy gap of prepared samples from 3.94-3.5 eV and 4.92-4.4 eV, respectively. This behavior is related to the network forming ability of Cr2O3. FTIR spectra of Cr2O3 containing glass showed some differences compared to base glass samples. In addition, calculated physical and optical parameters reveals a close similarity to base glass that can be correlated to the minor addition of Cr2O3.