Effect of Zr ions on the structure and optical properties of lithium borosilicate molybdate glass system

The glass system with the composition (20-x) MoO₃– x ZrO₂–15 SiO₂– 65 Li₂B₄O₇, x = 0, 1, 2, 3, 4, and 5 mol %] was successfully synthesized using the melt quenching method. The XRD results of this glassy system confirmed the glassy nature of the prepared glasses. The density of this glassy system presented higher values while the molar volume provided lower values with increasing ZrO₂ content. The FTIR result showed that the spectrum of each sample consisted of broad bands that de-convoluted into several peaks. These peaks were characterized and the structure of each sample was recognized. Additionally, the optical measurements showed that sample x = 0 mol% provided a sharp ultra-violet cut-off at 380 nm, while the other samples showed a transition peak in the (210–230) nm range. The energy of optical band gaps of these glass samples decreased and the Urbach energy increased by increasing ZrO₂ content. Moreover, the different optical parameters of these glass samples were calculated and showed that the studied glasses could be considered promising materials to be used in different optical applications such as nonlinearity and optoelectronics.