Addition of V2O5 in lithium aluminium oxy-fluorophosphate glass system: A possible glassy cathode?

Glass formation region in ternary LiF‒Al(PO ₃) ₃‒V ₂O ₅ system was determined by melt quenching technique. Homogeneous glasses were obtained by varying V ₂O ₅ between 2‒70 mol%. 80LiF‒20Al(PO ₃) ₃ composition was chosen as parent glass. V ₂O ₅ was added until stable glasses could be cast. V ₂O ₅ was substituted for LiF and/or Al(PO ₃) ₃ to test its role as glass modifier and/or glass former in presence of Al(PO ₃) ₃ . Glasses were characterized using XRD, DSC, ICP-AES, FTIR and Electrical Impedance Spectroscopy. V ₂O ₅ played dual role‒ of network modifier at low concentrations and of network former with its progressive additions, changing glass structure from predominantly phosphate to vanadophosphate network. These structural changes correlated with the measured properties. Electrical conductivity increased substantially upon V ₂O ₅ addition and changed from being predominantly ionic to mixed conduction, with comparable ionic and electronic contributions for ≥ 35 mol% of V ₂O ₅, making it a possible candidate for glassy cathode.