PREPARATION OF STRONTIUM DOPED BETA-LITHIUM VANADIUM BRONZES BY MOLTEN-SALT ELECTROLYSIS

The ionic-electronic conducting compounds of beta-strontium vanadium bronzes and strontium doped beta-lithium vanadium bronzes were obtained by electrolysis in a molten V2O5-SrCO3 system and a V2O5-SrSO4-Li3PO4 SYStem, respectively. The electrolysis conditions were examined by the cyclic voltammograms of the electrolytic bath at 700 -800-degrees-C. The mixture melt Of V2O5 containing 16.7 mol% SrCO3 and that containing both 4.5 mol% SrSO4 and 4.5 mol% Li3PO4 were the most suitable for beta-Sr0.18V2O5 and beta-Li0.14Sr0.08V2O5 crystallization, respectively. The lithium and strontium contents in beta-strontium and lithium doped vanadium bronzes were controlled with a current density and composition of the electrolytic bath. The conductivity for strontium doped beta-lithium vanadium bronzes was higher than the undoped beta-lithium bronzes. The activation energy was ca.0.20 eV for beta-Li0.17Sr0.09V2O5. Beta-Sr0.18V2O5 and beta-Li0.30V2O5.