Lu-doped zirconia (LuDZ) was reported in the 1960s to be a poor oxygen ion conductor. However, we identified this system as worthy of reexamination based on the results of a machine learning-based screen for promising oxygen ion conductors, further supported by a physical argument: because Lu is the heaviest and smallest of the lanthanides, it should offer the possibility of high conductivity due to its high polarizability and size compatibility with the zirconia structure. The relationship between dopant concentration and conductivity in the LuDZ system was determined using a high throughput experimental methodology in which spatially resolved conductivity was measured across a compositionally graded film, spanning from Zr_0.93Lu_0.07O_1.965 to Zr_0.82Lu_0.18O_1.91. The conductivity broadly peaks with composition at 15 cation % Lu, coinciding with the approximate phase boundary of the fully stabilized cubic phase. The composition-dependent conductivity measurements reveal a surprising increase in activation energy for ion transport with increasing Lu content with no change in this trend at the composition of the conductivity maximum. The pre-exponential factor increases sharply with Lu content, but displays a distinct plateau once the conductivity maximum composition is attained. At 500 °C, the conductivity of Zr_0.85Lu_0.15O_1.925 is 2 × 10⁻³ S cm⁻¹, approaching that of optimally doped Sc-stabilized zirconia, which has the highest reported conductivity among zirconia compounds. In comparison to other oxide ion conductors, Lu-stabilized zirconia offers the advantage over ceria of negligible electronic conductivity and is easier to process than (La,Sr)(Ga,Mg)O_3-δ.

1960 年代，据报道掺 Lu 的氧化锆 (LuDZ) 是一种不良的氧离子导体。然而，我们根据基于机器学习的氧离子导体筛选结果确定该系统值得重新检查，并得到物理论证的进一步支持：因为 Lu 是镧系元素中最重和最小的，它应该提供可能性由于其高极化率和与氧化锆结构的尺寸相容性，因此具有高导电性。LuDZ 系统中掺杂剂浓度和电导率之间的关系是使用高通量实验方法确定的，其中在组成渐变的薄膜上测量空间分辨电导率，范围从 Zr _0.93 Lu _0.07 O _1.965到 Zr_0.82 Lu _0.18 O _1.91 . 电导率在 15 阳离子 % Lu 处的组成中出现广泛的峰值，与完全稳定的立方相的近似相界一致。组成相关的电导率测量结果显示，随着 Lu 含量的增加，离子传输的活化能出人意料地增加，而在电导率最大值的组成下，这种趋势没有变化。指前因子随 Lu 含量急剧增加，但一旦达到电导率最大组成，则显示出明显的平稳状态。在 500 °C 时，Zr _0.85 Lu _0.15 O _1.925的电导率为 2 × 10 ^-3  S cm ^-1，接近最佳掺杂的 Sc 稳定氧化锆，其在氧化锆化合物中具有最高的电导率。与其他氧化物离子导体相比，Lu 稳定的氧化锆与氧化铈相比具有可忽略不计的电子电导率的优势，并且比 (La,Sr)(Ga,Mg)O _3-δ更容易加工。