Structural and optical properties of CuO in zinc phosphate glasses and effects of gamma irradiation

• Zinc phosphate glasses containing different CuO ratios were prepared.
• The absorption edge shifts towards higher wavelengths as the CuO content increases.
• Optical band gap values are affected by the CuO content and gamma irradiation.
• Deconvolution process is obtained for the base glass and the highest ratio of CuO.

Collective optical and infrared measurements have been employed to investigate the state of increasing copper ions in host 0.5ZnO–0.5P2O5 glass composition. The same spectral measurements were repeated after gamma irradiation with a dose of 20 and 80 KGy. Optical absorption spectra reveal strong UV absorption due to trace ferric ions present as unavoidable impurities within the chemicals used in the preparation of the glasses. Copper containing glasses show an additional broad visible-near infrared band due to distorted octahedrally coordinated Cu2+ ions which at high CuO contents exhibit splitting to several component absorption peaks. Gamma irradiation causes several variations between the response of the base host zinc phosphate glass and effect of increasing CuO. These changes are correlated with both the formation of induced defects through suggested photochemical reactions in the UV region and some shielding effects with increasing CuO in the visible-near infrared spectrum. Infrared absorption spectra reveal repetitive vibrational bands due to phosphate groups mainly from metaphosphate units and the spectra show some variations with the increase of CuO content visualize by the increase of the intensity of the mid broad band extending in the range 800–1500 cm−1.