Spectroscopic Studies of Na2O-BI2O-B2O3 Glasses Doped with MoO3

摘要

Alkali oxy borate glasses are well known due to their variety of applications in phosphors, solar energy converters and in a number of electronic devices. These glasses have high mechanical strength when compared with the pure borate glasses. On the other hand heavy metal oxide (Bi2O3) glasses owing to high refractive index such glasses exhibit non-linear effects. Besides, high density and transparency of these glasses make them useful for a variety of optical applications such as radiation shielding windows and scintillation counters. Extensive studies on several spectroscopic properties like optical, Electron Spin Resonance and Fourier Transform Infrared of various alkali borate glasses doped with different transition and rare earth metal ions are available. Among various transition metal oxide doped glasses, the Moo3 doped borate glasses have gained much importance in recent years MoO3 is known to have a structure composed of Mo pyramidsglasses show a semi conducting behavior with the electrical conductivity of 10-3 to 10-5 (ohm-cm)-1 which is known to be electron transfer between MO ions, existing in the structure of the glass. Further the conductivity in these glasses can be explained by a small polaron hopping theory. Further vanadium glasses are identified as n-type semiconductor s molybdenum ions are expected to dissolve easily in borate network because some of the infrared vibrational bands lie in the same region as those of BO3 and BO4 structural units. Virtually no devoted studies on spectroscopic studies such as optical absorption, electron spin resonance and FTIR on alkali borate glasses doped with Moo3 transition metal are available. Study on these properties of glasses helps in assessing their structural aspects and can also be used as a tool to throw some light on the insulating/conducting character of the glasses.The objective of the work incorporated in the dissertation is to have some understanding over the influence of MoO3on the structural aspects of Na?2O-Bi2O3-B2O3 from a systematic study of optical absorption, FTIR spectra. The following composition is chosen for the present study:10Na2O-(20-x) Bi2O3-70B2O3:xMoO3with x ranging from 0 to 3.0 wt%.