High lithium ionic conductivity of garnet-type oxide Li7+xLa3Zr2-xSmxO12 (x = 0–0.1) ceramics

• Published in: Materials letters Vol. 231; pp. 43 - 46
• Main Authors: Wang, Xishu, Liu, Jie, Yin, Rui, Xu, Yichen, Cui, Yonghua, Zhao, Liang, Yu, Xibin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.11.2018
• Subjects: Ceramics; Garnet; Ionic conductor; Sintering; Solid electrolytes; Garnet; Solid electrolytes; Ceramics; Sintering; Ionic conductor
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2018.08.006

•Good sinterability of Li7La3Zr2O12 is obtained by adding Sm3+.•Li7.06La3Zr1.94Sm0.06O12 could be promising Li-ion solid electrolytes.•The total ion-conductivity of Li7.06La3Zr1.94Sm0.06O12 ceramic pellets reach up to 2.46 × 10−4  S·cm−1. Li7La3Zr2O12 (LLZO) garnet is one of the most promising Lithium-ion solid electrolytes in all-solid-state Lithium-ion batteries, due to its higher chemical stability to Li metal and relatively higher lithium-ion conductivity. To further increase the electrical conductivity of LLZO, Sm3+ is doped into the Zr4+ site of LLZO so that excess Li occupies the position of the octahedral. Thereby lithium ion transport and increasing ionic conductivity are promoted. The optimal addition of Sm3+ is 0.06. Li7+xLa3Zr2-xSmxO12 (LLZSO, x = 0.06) electrolyte with cubic phase is obtained with sintering at 1200 °C for only 3 h. It has higher relative density and better ionic conductivity than the pristine LLZO. Its bulk and total ionic conductivity are ∼6.4 × 10−4 S·cm−1 and 2.46 × 10−4 S·cm−1 at 20 °C, respectively.