Characterization of sodium lead silicate glasses containing low and high levels of Fe2O3 and effect of its replacement for Na2O

Abstract

Glass of the composition (mol%) (25-x) Na2O−xFe2O3−25PbO−50SiO2,x = 0, 0.25, 0.5, 1, 3, 5, 7, 10, 15, 16 and 20 (mol%) were prepared by the melt quenching method. The effect of replacing Fe2O3 for Na2O on the optical, structural, electrical and dielectric properties was studied. Experimental and theoretical density and XRD of the samples were also reported. Pb2+, Fe2+ and Fe3+ ions contributed to the UV-cut off and the developed bands in the visible and near IR regions. FTIR revealed the decrease of the SiO4 and increase of FeO4 units. XRD indicated change in the glass structure above 15 mol% Fe2O3. The electrical conduction seems to occur by ionic and electronic controlled electron hopping between Fe2+ and Fe3+ sites. The activation energy of ionic conduction decreased from 1.74 eV for un-replaced Na2O sample to 0.16 eV for sample with 16 mol% Fe2O3 at 1 MHz. Samples with 16 and 20 (mol% Fe2O3) showed e′ values in the range from 115 to 186 and from 34 to 66, respectively. These results present promising candidates for the studied glasses to be used as energy storage materials in electronic devices.