Abstract
Metal fluorides present a high redox potential among the conversion-type compounds, which make them specially work as cathode materials of lithium ion batteries. To mitigate the notorious cycling instability of conversion-type materials, substitutions of anion and cation have been proposed but the role of foreign elements in reaction pathway is not fully assessed. In this work, we explored the lithiation pathway of a rutile-Fe0.9Co0.1OF cathode with multimodal analysis, including ex situ and in situ transmission electron microscopy and synchrotron X-ray techniques. Our work revealed a prolonged intercalation-extrusion-cation disordering process during phase transformations from the rutile phase to rocksalt phase, which microscopically corresponds to topotactic rearrangement of Fe/Co-O/F octahedra. During this process, the diffusion channels of lithium transformed from 3D to 2D while the corner-sharing octahedron changed to edge-sharing octahedron. DFT calculations indicate that the Co and O cosubstitution of the Fe0.9Co0.1OF cathode can improve its structural stability by stabilizing the thermodynamic semistable phases and reducing the thermodynamic potentials. We anticipate that our study will inspire further explorations on untraditional intercalation systems for secondary battery applications.
| Original language | English |
|---|---|
| Pages (from-to) | 10276-10283 |
| Number of pages | 8 |
| Journal | ACS Nano |
| Volume | 14 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - 2020 Aug 25 |
Bibliographical note
Funding Information:This work is supported by the Center for Functional Nanomaterials, which is a US DOE Office of Science Facility, at Brookhaven National Laboratory under Contract No. DE- SC0012704. This research used XPD beamline (28-ID-2) of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. S.-M.B. at Brookhaven National Laboratory is supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the U.S. Department of Energy through the Advanced Battery Materials Research (BMR) Program, including Battery500 Consortium under contract DE-SC0012704. D.S. acknowledges support from the Strategic Priority Research Program (B) (Grant No. XDB07030200) of Chinese Academy of Sciences.
Funding Information:
This work is supported by the Center for Functional Nanomaterials, which is a US DOE Office of Science Facility, at Brookhaven National Laboratory under Contract No. DE- SC0012704. This research used XPD beamline (28-ID-2) of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. S.-M.B. at Brookhaven National Laboratory is supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the U.S. Department of Energy through the Advanced Battery Materials Research (BMR) Program including Battery500 Consortium under contract DE-SC0012704. D.S. acknowledges support from the Strategic Priority Research Program (B) (Grant No. XDB07030200) of Chinese Academy of Sciences.
Publisher Copyright:
Copyright © 2020 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Engineering(all)
- Physics and Astronomy(all)
