Effect of copper addition on lithium zinc borosilicate glass containing terbium oxide

Terbium lithium zinc borosilicate glass systems incorporating copper ions were prepared using a melt quenching technique. The structural and physical properties of the produced glass samples were investigated using X-ray diffraction (XRD), infrared (FTIR), and optical absorption (UV/Vis/NIR) spectroscopy. The non crystalline behavior of the glasses was confirmed by XRD analysis. FTIR clear that changing the ratio of terbium and copper ions did not affect the locations of the borate and silicate groups, but it affected the intensity of absorption and amount of BO4, SiO4 and BO3 groups. The UV-visible-NIR spectra of the glasses showed a strong absorption of Tb3+ ions in the NIR region (2190, 1942, 1867, and 1775 nm for samples free of copper). The highest band gap value was obtained for the sample free of copper glass, which had the lowest amount of non-bridging oxygen. The estimated CIE coordinates for the glasses show their locations in the blue-green region for samples free from copper when excited at 250 nm and green when the sample was excited at 378 nm. And move to green region with the copper content increased. The CIE coordinates deviated towards the yellow region when excited at 378 nm and became green yellowish with increasing Tb concentration.