Spectroscopic investigations on PbO–As₂O₃ glasses crystallized with TiO₂

Abstract

PbO–As₂O₃ glasses mixed with different concentrations of TiO₂ (ranging from 0 to 1.0 mol%) were crystallized. The samples were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy (EDS) techniques. Studies were extended to optical absorption, IR, ESR, luminescence and magnetic susceptibility on these samples. The X-ray diffraction studies reveal the presence of Pb₃O₄, Ti(As₂O₇), Pb(As₂O₆), Pb₃(AsO₄)₂ PbTi₃O₇ and Ti₂O₃ crystal phases. The optical absorption studies together with ESR and magnetic susceptibility measurements indicated that the titanium ions exist in both Ti³⁺ and Ti⁴⁺ states in all the samples and there is an increase in titanium ions in the trivalent state with increasing concentration of nucleating agent TiO₂. The quantitative analysis of these results indicated that there is a growing degree of disorder in the glass network with increasing concentration of the crystallizing agent. The luminescence studies indicated that the samples crystallized with low concentrations of TiO₂ show high luminescence efficiency in the visible region.

Keywords:

• electron paramagnetic resonance
• glass
• infrared
• optical properties
• titanium oxide