Effect of Substituting B 2 O 3 for P 2 O 5 in Conductive Vanadate Glass

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.