Structural and optical properties of tungsten-sodium-zinc-borate glass doped α-Fe2O3 nanoparticle

The effect of α-Fe2O3 nanoparticles on the structural, physical, and optical properties of the synthesized glass (45-x) B2O3 + 10WO3 + 20Na2O +25ZnO + xα-Fe2O3 (where x = 0, 0.1, 0.3, 0.5, 0.7, and 1) via melt quenching technique was investigated. XRD and FTIR analysis confirmed the glass's amorphous nature in the absence of peaks in the spectrum and the presence of BO4 and BO3 structural units. The density increases while the molar volume decreases, with increasing dopant content. The FTIR analysis further reveals that the intensity of the B–O–B bond decreases as the α-Fe2O3 content increases, implying that the B–O–B bond in the bond ring isolated to BO3 units transforms into BO4 units. Also, the optical direct and indirect band gap decreases from 3.60 to 2.18 eV and 3.68 to 2.07 eV, respectively. The transmission coefficient decreases from 0.9 to 0.48, while the reflectance loss increases from 0.05 to 0.35 as dopant content increases. Urbach energy, interatomic separation, and metallization decrease, while the refractive index, molar refractivity, electronic polarizability, and dielectric constant increase with increasing dopant concentration. The refractive index based on metallization M(n) and optical band gap based on metallization M (Eopt) decreases from 0.66 to 0.18 and 0.43 to 0.33, respectively. Adding α-Fe2O3 reduced the bandgap energy and transformed the glass insulator qualities into semiconductor properties. The data show that the as-prepared glass is a possible candidate for photonic applications.