Exploring the interplay of structure, optical, magnetic and radiation shielding properties in GeO2/Bismuth borate glasses

Abstract

This article investigates the structural, chemical, optical, and magnetic properties of borate bismuth glasses doped with increasing GeO2 concentrations. X-ray diffraction (XRD), Raman spectroscopy, density measurements, thermal analysis, UV–Vis absorption, and VSM studied the impact of GeO2 on the glass network. The XRD results of the study confirmed that glass is amorphous. The bulk density increased while the molar volume decreased with increasing GeO2 concentration. Glass transition temperature (Tg) slightly decreases due to weaker Ge–O bonds and lower cross-linking density. Crystallization temperature (Tc) increased as GeO2 disrupts the network, hindering crystal nucleation and growth. Optical band gap narrows with increasing GeO2, with direct and indirect gaps decreasing. Urbach energy (EU) rises with GeO2, indicating increased disorder in the glass network. Refractive index (n) and extinction coefficient (k) both increased with GeO2, attributed to non-bridging oxygen formation. VSM measurements reveal an increase in saturation magnetization from 0.1 to 0.3 emu/g with increasing GeO2 content. Mass attenuation coefficient (MAC) and linear attenuation coefficient (LAC) investigations showed the efficiency of the glass system for radiation attenuation at varying energies. The unique properties of these borate bismuth glasses doped with GeO2 show promise for various technological advancements in optoelectronics and radiation shielding.