(A2-xLix)Ti2O7-x (A1LT, x = 0.04 – 0.11) (A = Y、Gd),兩系列樣品分別在1150和1250 oC下燒結10 h。比較A1LT和 A2-xTi2O7 (AT)系列樣品的晶胞參數,發現在相同取代量x的情況下,A1LT系列的晶胞參數會大於AT系列的晶胞參數,這表示Li+成功的取代至A1LT樣品A site的位子。利用添加兩倍的Li2O至A1LT系列樣品,即為(A2-xLi3x)Ti2O7 (A3LT)系列,A3LT與A1LT在相同取代量x的條件下,會有相同的晶胞參數。因此,添加額外的Li2O可當作助熔劑的功用,藉由固態共熔點的產生而降低A3LT樣品的熔點,使A3LT材料獲得改善,且有較大的晶粒。添加Li2O當助熔劑至A1LT系列樣品和燒結時的溫度控制,可使(A2-xLix)Ti2O7-x (A1LT, x = 0.04 – 0.11) (A = Y 、Gd)系列在相同的燒結溫度(分別為1150和1250 oC 10 h),樣品的相對緻密度均在90 % 以上。Y3LY系列中取代量為x = 0.06樣品在700 ℃時的導電度時為4.07 × 10-4S.cm-1;而根據報導指出,相較於Y2Ti2O7樣品在700度C的導電度為2.03X10-4S.cm-1,卻要以1600度C燒結。
Two series of (A2-xLix)Ti2O7-x (A1LT, x = 0.04 – 0.11) with A = Y and Gd were sintered at 1150 and 1250 oC respectively for 10 h in the static air atmosphere. Unit cell a-axis of the A1LT is longer than that of the A2-xTi2O7 (AT) with the same amount of x and the same A site cation, indicating a successful substitution of the Li+ ion into the A site of A1LT. Addition of extra Li2O (2x) into A1LT, the nominal composition becomes (A2-xLi3x)Ti2O7 (A3LT), which has the same unit cell a-axis as A1LT with the same amount of x. Therefore, the extra Li2O added in the A3LT is probably acting as a self flux to lower the melting point of the mixture. As a result, materials become more compact and grains grow bigger. Adding Li2O as a flux and the heating history is carefully controlled, compact samples of (A2-xLix)Ti2O7-x (A1LT, x = 0.04 – 0.11) with A = Y and Gd with relative density higher than 90% can be obtained at a temperature as low as 1150C and 1250C respectively. One compound of Y3LT with x=0.06 prepared at 1150C had an AC conductivity of 4.07 x10-4S/cm at 700C, the ionic conductivity is comparable to a Y2Ti2O7 prepared at 1600C that is 2.03x10-4 S/cm reported.