Synthesis, Structure and Electrical Conductivity of Li-substituted Bi4v2o11 Solid Electrolyte

The series of compounds Bi_4-xLi_xV₂O_11-δ-(0≤x≤0.4) has been prepared using solid state reaction technique. The crystal structure and conductivity were studied by using XRD and ac impedance spectroscopy. All the compounds exhibit α-typephase structure at room temperature. The β-phase appears to be suppressed for doped compounds. The conductivity of all the substituted phases is found to be higher than the parent compound. The highest conductivity (1.02×10^-3 S/cm at 420°C) as compared to the parent compound was observed for x=0.3 substitution. The higher ionic conductivity for the doped compounds has been correlated with excess oxygen vacancies created by aliovalent substitution.