M/Li+(M = Mg2+, Zn2+, and Mn2+) ion-exchange on lithium ion-conducting perovskite-type oxides and their properties

Lithium ions of perovskite-type lithium ion conductor La0.55Li0.35TiO3 were replaced by divalent Mg2+, Zn2+, and Mn2+ ions in an ion-exchange reaction using molten chlorides. The polycrystalline Mg-exchanged and Zn-exchanged samples are solid electrolytes for divalent Mg2+ and Zn2+ ions, whose dc ionic conductivities (σ = 2.0 × 10− 6 S cm− 1 at 558 K for the Mg-exchanged sample, La0.56(2)Li0.02(1)Mg0.16(1)TiO3.01(2) and σ = 1.7 × 10− 6 S cm− 1 at 708 K for the Zn-exchanged samples, La0.55(1)Li0.0037(2)Zn0.15(1)TiO2.98(2)) were compared to those of the known highest Mg2+ and Zn2+ inorganic solid electrolytes. The Mn-exchanged sample, then, showed paramagnetic behavior in the temperature range of 2 to 300 K. The Mn ions in the exchanged sample are divalent and the spin configuration is in high spin state (S = 5/2).