An efficient multi-doping strategy to enhance Li-ion conductivity in the garnet-type solid electrolyte Li7La3Zr2O12

Yedukondalu Meesala, Yu Kai Liao, Anirudha Jena, Nai Hsuan Yang, Wei Kong Pang, Shu Fen Hu, Ho Chang, Chia Erh Liu, Shih Chieh Liao, Jin Ming Chen, Xiangxin Guo, Ru Shi Liu

Research output: Contribution to journalArticlepeer-review

22 Citations (Scopus)


Lithium-ion (Li+) batteries suffer from problems caused by the chemical instability of their organic electrolytes. Solid-state electrolytes that exhibit high ionic conductivities and are stable to lithium metal are potential replacements for flammable organic electrolytes. Garnet-type Li7La3Zr2O12 is a promising solid-state electrolyte for next-generation solid-state Li batteries. In this study, we prepared mono-, dual-, and ternary-doped lithium (Li) garnets by doping tantalum (Ta), tantalum-barium (Ta-Ba), and tantalum-barium-gallium (Ta-Ba-Ga) ions, along with an undoped Li7La3Zr2O12 (LLZO) cubic garnet electrolyte, using a conventional solid-state reaction method. The effect of multi-ion doping on the Li+ dynamics in the garnet-type LLZO was studied by combining joint Rietveld refinement against X-ray diffraction and high-resolution neutron powder diffraction analyses with the results of Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and multinuclear magic angle spinning nuclear magnetic resonance. Our results revealed that Li+ occupancy in the tetrahedrally coordinated site (24d) increased with increased multi-ion doping in LLZO, whereas Li+ occupancy in the octahedrally coordinated site (96h) remained constant. Among the investigated compounds, the ternary-doped garnet structure Li6.65Ga0.05La2.95Ba0.05Zr1.75Ta0.25O12 (LGLBZTO) exhibited the highest total ionic conductivity of 0.72 and 1.24 mS cm-1 at room temperature and 60 °C, respectively. Overall, our findings revealed that the dense microstructure and increased Li+ occupancy in the tetrahedral-24dLi1 site played a key role in achieving the maximum room-temperature Li-ion conductivity in the ternary-doped LGLBZTO garnet, and that the prepared ternary-doped LGLBZTO was a potential solid electrolyte for Li-ion batteries without polymer adhesion.

Original languageEnglish
Pages (from-to)8589-8601
Number of pages13
JournalJournal of Materials Chemistry A
Issue number14
Publication statusPublished - 2019

ASJC Scopus subject areas

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)


Dive into the research topics of 'An efficient multi-doping strategy to enhance Li-ion conductivity in the garnet-type solid electrolyte Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub>'. Together they form a unique fingerprint.

Cite this