• Media type: E-Article
  • Title: Effect of Sintering Process on Ionic Conductivity of Li7-xLa3Zr2-xNbxO12 (x = 0, 0.2, 0.4, 0.6) Solid Electrolytes
  • Contributor: Ni, Lei; Wu, Zhigang; Zhang, Chuyi
  • Published: MDPI AG, 2021
  • Published in: Materials, 14 (2021) 7, Seite 1671
  • Language: English
  • DOI: 10.3390/ma14071671
  • ISSN: 1996-1944
  • Origination:
  • Footnote:
  • Description: Garnet-type Li7La3Zr2O12 (LLZO) is considered as a promising solid electrolyte. Nb-doped LLZO ceramics exhibit significantly improved ion conductivity. However, how to prepare the Nb-doped LLZO ceramics in a simple and economical way, meanwhile to investigate the relationship between process conditions and properties in Li7-xLa3Zr2-xNbxO12 ceramics, is particularly important. In this study, Li7-xLa3Zr2-xNbxO12 (LLZNxO, x = 0, 0.2, 0.4, 0.6) ceramics were prepared by conventional solid-state reaction. The effect of sintering process on the structure, microstructure, and ionic conductivity of LLZNxO (x = 0, 0.2, 0.4, 0.6) ceramics was investigated. Due to the more contractive Nb-O bonds in LLZNxO ceramics, the cubic structures are much easier to form and stabilize, which could induce the decreased preparation time. High-performance garnet LLZNxO ceramics can be obtained by optimizing the sintering process with lower calcining temperature and shorter holding time. The garnet samples with x = 0.4 calcined at 850 °C for 10 h and sintered at 1250 °C for 4 h exhibit the highest ionic conductivity of 3.86 × 10−4 S·cm−1 at room temperature and an activation energy of 0.32 eV, which can be correlated to the highest relative density of 96.1%, and good crystallinity of the grains.
  • Access State: Open Access