Influence of chromium ions on dielectric and spectroscopic properties of Na₂O-PbO-B₂O₃glass system

Abstract

Na 2 O-PbO-B 2 O 3 glasses doped with Cr 2 O 3 by varying its concentration relative to borate (in the range of 0 to 0.2 mol% in steps of 0.05 mol %) are prepared. Dielectric studies ( dielectric constant , loss tan , conductivity ac etc in the frequency range 10 3 to 10 6 Hz and in the temperature range 30 to 250 o C) and spectroscopic properties like IR & ESR etc. were carried out on these samples. From these studies it was noticed that chromium with Cr 6+ ions exist in network forming positions at low concentration i.e., at 0.05 mol% beyond which Cr 6+ ions gradually get converted into Cr 3+ ions, there by act as network modifiers and decrease the rigidity of the glass network. IntroductionAlkali oxy borate glasses have variety of applications in phosphors, solar energy converters and in a number of electronic devices. These glasses are relatively moisture resistant. They possess high electrical insulating and mechanical strength when compared to pure borate glasses. Alkali oxy borate glasses are transparent from near UV to the middle infrared region. Addition of alkaline earth oxides like CaO, BaO, MgO, PbO etc., in to these glass matrices is expected to increase their resistance against moisture. Now-a-days, much attention has been paid to research in inorganic glasses doped with transition metal ions, because of their technological importance in the development of tunable solid state lasers, new luminescence materials, solar energy converters and fiber optic communication devices [1][2][3][4]. Among various transition metal ions, chromium ions have strong bearing on optical, magnetic and electrical properties of glasses. The present investigation is under taken to probe the local environment of chromium ion in Na 2 O-PbO-B 2 O 3 glass matrix and its impact on dielectric properties.

Influence of modifier oxide on spectroscopic characteristics of neodymium ion in lithium borate glass system

“…Both ZnO and CdO are thermally stable and appreciably covalent in character 16 . Resistance to the moisture of these glasses is expected to increase by addition of the alkaline-earth oxide CaO into these glass matrices 17 . The glasses mixed with Li 2 O as network modifier was seen as moisture resistant, highly stable, and bubble free, is suitable for a good systematic optical analysis 18 .…”

Impact of Rare-Earth Ion Doping on Dielectric Properties of Li2O-CaO-B2O3 Glass System

“…Addition of alkaline-earth oxide CaO into these glass matrices is expected to increase the resistance of the glasses to the moisture. 2 Among the many alkali oxides that act as network adapters, such as Li 2 O, Na 2 O, and K 2 O, the Li 2 O-containing glass was non-abrasive, incredibly stable, resistant to moisture, and acceptable for systematic optical investigations. 3 The addition of Na 2 O and K 2 O was not explored in the current study because of this reason.…”