||Synthesis, structure and ionic conductivity of lithium ion conductors with perovskite and pyrochlore structures
Synthesis, structure and ionic conductivity of lithium ion conductors with perovskite and pyrochlore structures
ﾌﾟﾗｰｵﾋﾟﾊﾟｯﾄ, ﾀﾝﾔｰPHRAEWPHIPHAT, THANYA
Structures and ionic conductivities of the new perovskite oxides and pyrochlore oxyflurides were investigated. Solid solutions of the new perovskite oxides, (LixSr1-x-y)(Ga[(1-x)/2]-yTa[(1+x)/2]+y)O3, were synthesized using a ball-mill-assisted solid-state reaction with the composition range of 0 ≤ y ≤ 0.20. The highest ionic conductivity was obtained for the composition of x = 0.25 and y = 0.125. Introduction of vacancies at the A-sites, which was determined by neutron diffraction analysis, leads to higher ionic conductivities. Lithium containing pyrochlore oxyflurides, LiSrB2O6F, Li1.1SrB1.9Zr0.1O6F and LiSr0.9B2O6F0.8 with B = Nb+5 and Ta+5, were synthesized by a high-pressure method and their ionic conductivities were clarified. LiSr0.9B2O6F0.8 showed the highest ionic conductivity, which is due to the introduction vacancies at the A- and F-sites. Their structure-property relationships are discussed based on the structure and conductivity data.