Effect of Annealing on Optical Properties of ZnO·LiF·B2O3 Glasses

Abstract

The Melt-quench method is used to synthesize zinc fluoroborate glasses with compositions xZnO 5, 10, 15, and 20). Optical characterization was carried out to examine the variation of optical bandgap energy (E g ) and urbach energy (E U ) with respect to the concentration for the samples annealed at different temperatures (300• C, and 400• C). Annealing shows its effect on the samples with the variations in the values of E g and E U . These variations are explained on the basis of formation of different molecular species like BO 3 − units, boroxol rings, and the change in the number of nonbridging oxygen atoms.

Effect of CaO/MgO ratio on the optical and theoretical parameters of alumino‐borosilicate glasses

“…It can be observed that E dir and E ind values for heat‐treated glass samples are greater than those obtained for pristine glass samples. This could be attributed to the fact that during annealing BO 3 structural units might be formed, which connect together to form boroxol rings, thereby decreasing NBOs and increasing the optical band gap of the heat‐treated glasses . The formation of BO 3 units could be confirmed from FTIR investigations for the heat‐treated glasses (Section ), which depicts B–O bond vibrations (BO 3 stretching) at 1521‐1558 cm −1 .…”

Effect of stepwise replacement of LiF by ZnO on structural and optical ptroperties of LiF.B2O3 glasses

“…The flexible variance in the structures of borate glasses with the addition of LiF has been reported [2]. We have recently reported the study of LiF.B 2 O 3 glasses with concentrations varied by replacing LiF by Bi 2 O 3 [3,4]. ZnO, being a transition metal oxide, exhibits semiconducting properties.…”