SOME PROPERTIES OF AGI-AG2O-MOO3 ELECTROLYTE DOPED WITH AL2O3

Stoichiometric ratios of AgI, Ag2O and MoO3 were weighed into different crucibles. Different amounts of Al2O3 were added to all but one crucible so as to form the undoped ternary glassy 66.67 AgI- 14.29 Ag2O-19.04 MoO3 system and the 66.67 AgI- 14.29 Ag2O-19.04 MoO3 doped with 0.1, 0.3, 0.5, 0.7 weight % (w/o) of Al2O3 when the melts of these constituent chemicals were rapidly quenched in liquid nitrogen. The phases were characterized by XRD, electrical conductivity and transference number. The electrical conductivity at 300 K of the undoped glass is 0.003 S/cm and the doped sample with 0.5 w/o Al2O3 has the highest electrical conductivity at 300 K of 0.007 S/cm. These phases are solid electrolytes that were used to fabricate solid state electrochemical cells. The cell with the undoped electrolyte has an internal resistance of 150 OMEGA and the cell with the doped electrolyte (0.5 w/o Al2O3) has an internal resistance of 100 OMEGA. The differences observed in the characteristics of the doped and undoped phases and the differences in the battery performance are attributed to the chemical reaction between Al2O3 and the glass which resulted in a change of the glassy phase in the doped material.