4 research outputs found
Spectroscopic properties and dielectric dispersion of K<sub>2</sub>O-BaO-B<sub>2</sub>O<sub>3 </sub>glasses doped with Fe<sub>2</sub>O<sub>3</sub>
315-322Alkali borate
glasses doped with different concentrations of ferric oxide in the range 0-1
mol % in steps of 0.2 mol % have been prepared. The
dielectric properties, especially dielectric constant e¢, loss tand a c conductivity sac over a wide range frequency (1-100 kHz) and temperature (30-300°C), ESR and IR
spectra of Fe2O3 containing K2O-BaO-B2O3
glasses have been studied.
The dielectric study reveals that the glasses have high insulating strength
when Fe2O3 concentration is 0.8 mol % in the glass
matrix. The results have been analyzed in the light of different oxidation states
of iron ions with the help of IR and ESR spectra data. The analysis indicates
that when the concentration of iron ions is up to 0.8 mol %, these ions exist
in Fe3+ state that takes modifier as well as network former
position, beyond this concentration some of the iron ions switch over from Fe3+
to Fe2+ state that takes network modifier positions and weakens the
insulating strength of the glass