Effect of Substituting B2O3 for P2O5 in Conductive Vanadate Glass

Abstract

In this study, we verified the relationship among the electrical conductivity, chemical durability, and structure of conductive vanadate glass in which BO₃ and BO₄ and V 4+ and V 5+ coexist simultaneously. We prepared samples of vanadium borophosphate glass with various compositions, given by 50V₂O 5 -xB₂O₃-(50-x)P₂O 5 (x = 0 ~ 20 mol%) and 70V₂O 5 -xB₂O₃-(70-x)P₂O 5 (x = 0 ~ 10 mol%), and analyzed the electrical conductivity, chemical durability, FT-IR spectroscopy, thermal properties, density, and molar volume. Substituting B₂O₃ for P₂O 5 was found to improve the electrical conductivity, chemical durability, and thermal properties. From these results, we can draw the following conclusions. First, the electrons shift from the electron rich V 4+ to the electron deficient BO₃ as the B₂O₃ content increases. Second, the improvement in chemical durability and thermal properties is attributed to an increase in cross-linked structures by changing from a BO₃ structure to a BO₄ structure.