Improvement of Electrical Conductivity and Chemical Durability in Fe₂O₃ Doped V₂O 5-B₂O₃-P₂O 5 Glasses

J Nanosci Nanotechnol. 2019 Mar 1;19(3):1254-1260. doi: 10.1166/jnn.2019.16217.

Abstract

In this study, we verified the relationship among the electrical conductivity, chemical durability, and structure of conductive vanadate glass in which Fe2+-Fe3+ and V4+-V5+ systems simultaneously coexist. We prepared samples of iron vanadium borophosphate glass with various compositions given by 78V₂O5-15P₂O5-7B₂O₃-xFe₂O₃ (1, 5, 7.5 and 10 mol%) and analyzed the electrical conductivity, chemical durability, FTIR spectra, thermal properties, density, and molar volume. The results indicated that the addition of Fe₂O₃ improved the electrical conductivity, chemical durability, and thermal properties. The following conclusions could be drawn: Fe2+-O-P bonds or Fe3+-O-P bonds were generated in the glass structure, and Fe3+ and Fe2+ ions were located at tetrahedral and octahedral sites. Furthermore, V═O bonds were expected to be replaced with Fe-O-V and P-O-V bonds, which are stronger than double bonds, so that the complete glass structure was strong. The structural reinforcement of the glasses was additionally confirmed based on thermal and chemical properties and electrical conductivity.