Use of BaO-aided structural change of BaO–ZnO–TeO2 glass to enhance the optical properties of its doped activators by optimizing their surrounding ionic field

Abstract

Spectroscopic studies of BaO effect on the Yb3+-doped BaO–ZnO–TeO2 glasses of varied BaO content reveal that the integrated emission of constant amount of Yb3+ in these glasses increases with the increase in BaO. Excitation spectra exhibit a phonon progression of ~ 150 cm−1, while FTIR spectra of the glasses show a phonon at ~ 700 cm−1; intensity of both increases with increase in BaO. The phonons are identified, respectively, as the rotational and stretching vibrations of loosely bound tellurite (TeO3−/Te2O52−) units of the host’s structure, concentration of which increases with the increase in BaO. Specific volume data, XRD, HRTEM investigations suggest that large Ba2+ ions in these glasses attract the tellurite units toward its vicinity inducing a compaction. Ba2+-substituted Yb3+ ions in the glass because of higher charge density attract the tellurite units even closer and experience greater ionic field exhibiting efficient luminescence. Glass is potential host for designing new generation efficient optical materials.