Structure and Electrical Properties of Iron Borosilicate Glasses

Glasses of nominal composition 25SiO(2)-30Na(2)O-2Al(2)O(3)-xFe(2)O(3)-(43-x)B2O3(x = 1 to 6 mol%) were prepared by the ordinary melt quenching technique. The influence of Fe2O3 substitution at the expense of B2O3 on structure and electrical conductivity of sodium borosilicate glasses was investigated. The conductivity was found to increase with increasing Fe2O3 content. A double channel conduction mechanism was introduced to explain the electrical conductivity measurements. Moreover, the activation energy decreases considerably in the temperature range from 473 to 773 degrees K. The activation energies of conduction in various temperature regions were calculated. The conduction was best described by sodium ion migration and hopping between the two valence states of iron. FTIR absorption spectra in the spectral range 1600-400 cm(-1) were measured and a deconvolution analysis technique (DAT) using Gaussian peaks was introduced to analyze the studied glasses. Different characteristic bands were observed and attributed to different types of borate besides silicate vibrational groups.