Structural, optical, thermal and other physical properties of Bi2O3 modified Lithium Zinc Silicate glasses

Abstract

A series of 60SiO2–15ZnO-(25-x)Li2O-xBi2O3 glasses with x = 0, 5, 10, 15 and 20 mol% were synthesized using conventional melt-quenching method and their amorphous nature was ascertained by X-ray diffraction technique. The variation in physical parameters viz. density (ρ), crystalline volume (Vc), molar volume (Vm) and oxygen packing density (OPD) with composition of as- prepared glass samples has been analyzed. The physical properties related parameters such as average value of silicon- silicon (Si-Si) separation 〈dSi-Si〉, polaron radius (Rp), Bi3+ ion concentration (N), bismuth yield field strength (F) and interionic distance (Ri) have been determined. Investigations of infrared and Raman spectra reveal that tetrahedral [ZnO4] and [SiO4] structural units are main building blocks of glass network, whereas, Bi2O3 exists as both network modifier octahedral [BiO6] and network former pyramidal [BiO3] structural units. Optical bandgap energy (Eg) values determined by UV–VIS-IR spectroscopy indicate a decreasing trend with increasing Bi2O3%. The as-prepared glasses possess relatively high values of the optical basicity (1.069–1.208), electronic oxide ion polarizability (4.522–7.893 Å3), third order non-linear optical susceptibility (0.086–0.922 × 10−11esu) and metallization criterion (0.2991–0.4396) thereby implying that the present glasses may be suitable in non-linear optical applications.