Defects of various types in crystalline and nanocrystalline materials govern a range of electrical, optical and mechanical properties. In particular, they are at the heart of translational ion dynamics in solid electrolytes. One of the most prominent examples revealing a drastic increase in ionic conductivity σ_DC by several orders of magnitude when going from an ordered crystalline matrix to a structurally disordered one is lithium tantalate. Here, structurally disordered, nanocrystalline LiTaO₃ served as a model substance to shed light on the question to what extent the degree of disorder decreases upon annealing an originally defect-rich oxide. Disorder can be introduced by high-energy ball milling of LiTaO₃ crystallites with diameters in the μm range. Broadband conductivity spectroscopy, EXAFS and positron annihilation lifetime spectroscopy were used to correlate ion transport properties with interatomic distances, bond distortions and positron lifetimes. It turned out that milling times of only 30 min are sufficient to generate a highly defective oxide. Upon annealing at temperatures of T = 200 °C the defects can almost be preserved. Annealing at 750 °C for 1 h is needed to induce healing of the defects. Although we observe a recovery of the original interatomic distances and an increase in activation energy E_a for ionic transport from 0.75 eV to 0.81 eV, the initial transport properties of the unmilled sample (0.97 eV) cannot be fully restored. Most interestingly, the change in E_a is accompanied by a change of the entropy-controlled Arrhenius pre-factor governing the temperature dependence of σ_DCT. Moreover, positron lifetimes remain high in the annealed samples. Hence, our results point to samples with fewer distortions but still rich in vacancy-type defects. Altogether, the combination of ball milling and annealing helps adjust ionic conductivities in LiTaO₃ to vary over 4 to 5 orders of magnitude.

晶体和纳米晶体材料中的各种缺陷控制着一系列的电，光和机械性能。特别地，它们是固体电解质中平移离子动力学的核心。其中最突出的例子揭示在离子导电性急剧增加σ _DC从去时由几个数量级的有序的结晶基质的结构无序一个是钽酸锂。此处，结构无序的纳米晶体LiTaO ₃用作模型物质，阐明了在对最初富含缺陷的氧化物进行退火后，无序度降低到何种程度的问题。LiTaO ₃的高能球磨会导致紊乱直径在μm范围内的微晶。宽带电导率光谱，EXAFS和正电子lifetime没寿命光谱用于将离子传输特性与原子间距离，键畸变和正电子寿命相关联。事实证明，仅30分钟的铣削时间就足以产生高度缺陷的氧化物。在T  = 200°C的温度下退火时，几乎可以保留缺陷。需要在750°C下退火1小时以诱导缺陷的愈合。尽管我们观察到原始原子间距离的恢复和活化能E _a的增加对于从0.75 eV到0.81 eV的离子迁移，未完全研磨样品的初始迁移特性（0.97 eV）无法完全恢复。最有趣的是，在改变ë_一个伴随理事的温度依赖性的熵控制阿列纽斯预因子的变化σ _DC Ť。此外，在退火的样品中，正电子寿命仍然很高。因此，我们的结果表明样品的变形较少，但仍然富含空位型缺陷。总之，球磨和退火的组合有助于将LiTaO _3中的离子电导率调整为4到5个数量级。