“Heavy metal oxide glasses as a host media for transition or rare earth metal ions: characterization and evaluation”

Abstract

Heavy metal oxides glasses, having the chemical composition of (60PbO-20Bi2O3, mol%) and containing 20 mol% conventional glass formers SiO2, B2O3 or P2O5, were prepared by the melt-quenching method. Combined optical and Fourier transform infrared absorption spectra were measured for the prepared glasses to justify the role of glass formers in the optical spectra together with the network structural groups in these glasses. Additionally, the density was measured using Archimedes method and molar volume values were calculated to obtain some insight on the compactness and arrangement in the glass network. Optical measurements have been used to determine the optical band gap (Eg), Urbach energy (∆E) and the refractive index (n). Optical spectra of all the samples reveal strong UV absorption which is related to the presence of unavoidable trace iron impurities (Fe3+ ions) contaminated within the raw materials which were used for the preparation of the studied glasses. Additional near visible bands are observed in all prepared glasses due to characteristic absorption of Pb2+ and Bi3+ ions. Furthermore, the variations of the luminescence intensity, values of optical band gap, band tail and refractive index can be understood and related to the structural changes that are taking place in the glass samples as a result of the composition variation.