The high-resistive grain boundaries are the bottleneck for Li⁺ transport in Li₇La₃Zr₂O₁₂ (LLZO) solid electrolytes. Herein, high-conductive LLZO thin films with cubic phase and amorphous domains between crystalline grains are prepared, via annealing the repetitive LLZO/Li₂CO₃/Ga₂O₃ multi-nanolayers at 600 °C for 2 h. The amorphous domains may provide additional vacant sites for Li⁺, and thus relax the accumulation of Li⁺ at grain boundaries. The significantly improved ionic conductivity across grain boundaries demonstrates that the high energy barrier for Li⁺ migration caused by space charge layer is effectively reduced. Benefiting from the Li⁺ transport paths with low energy barriers, the presented LLZO thin film exhibits a cutting-edge value of ionic conductivity as high as 6.36 × 10⁻⁴ S/cm, which is promising for applications in thin film lithium batteries.

高电阻晶界是Li ₇ La ₃ Zr ₂ O ₁₂（LLZO）固体电解质中Li ⁺传输的瓶颈。在此，通过将重复的LLZO / Li ₂ CO ₃ / Ga ₂ O ₃多层纳米层在600°C下退火2 h ，制得了具有立方相和晶粒之间的非晶域的高导电LLZO薄膜。非晶域可能为Li ⁺提供额外的空位，从而放松Li ⁺的积累在晶界处。跨越晶界的离子电导率显着提高，表明有效减少了由空间电荷层引起的Li ⁺迁移的高能垒。受益于低能垒的Li ⁺传输路径，本文介绍的LLZO薄膜具有高达6.36×10 ^-4  S / cm的离子电导率前沿值，这有望用于薄膜锂电池。