Abstract
Phase evolution during a thorough Li ion's insertion of electrode materials governs their battery performance during charge and discharge. Here we investigated the lithiation pathway of titanium disulfide using in situ TEM combined with synchrotron-based pair distribution function measurement and first-principles calculations. A 2D intercalation reaction proceeds along with a transition from van der Waals interaction between Ti–S slabs to the covalent bonding of S–Li–S, with no symmetry broken. Further lithiation triggers unconventionally multiple step conversion reactions as proved: LiTiS2→TiS→Ti2S→Ti. The conversion reaction pathway is also verified in fully discharged sample in coin-cell. The expanded conversion chemistry is supposed to increase the capacity of TiS2 electrode and downgrade the cyclability, whereas the existence of intermediate phases shows the promise of improving the reversibility with a successful control of the state of charge.
Original language | English (US) |
---|---|
Article number | 103882 |
Journal | Nano Energy |
Volume | 63 |
DOIs | |
State | Published - Sep 2019 |
Funding
Electron microscopy work was performed at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy , Office of Basic Energy Science , under contract No. DE-SC0012704 . M.Fu acknowledge the support of Visiting Scholar Research Program of NPU , the Fundamental Research Funds for the Central Universities ( 31020195C001 ) and Innovation and Development Program of Shaanxi Province ( 2017KTPT-03 ). Z.Y. (DFT calculations, analysis of results) and C.W. (leadership of DFT calculations) were supported as part of the Center for Electrochemical Energy Science (CEES), an Energy Frontier Research Center funded by the U.S. Department of Energy , Office of Science , Basic Energy Sciences under Award No. DE-AC02-06CH11357 . The authors gratefully acknowledge the computing resources from the National Energy Research Scientific Computing Center , a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 . This research used 28-ID-2 (XPD) of the National Synchrotron Light Source II, a U.S. Department of Energy Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704 . H.D. and Y.Y. acknowledges funding support from the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy ( DE-EE0008234 ), UH Technical Gap Fund , and UH High Priority Area Large Equipment Grant . Electron microscopy work was performed at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Science, under contract No. DE-SC0012704. M.Fu acknowledge the support of Visiting Scholar Research Program of NPU, the Fundamental Research Funds for the Central Universities (31020195C001) and Innovation and Development Program of Shaanxi Province (2017KTPT-03). Z.Y. (DFT calculations, analysis of results) and C.W. (leadership of DFT calculations) were supported as part of the Center for Electrochemical Energy Science (CEES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-AC02-06CH11357. The authors gratefully acknowledge the computing resources from the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. This research used 28-ID-2 (XPD) of the National Synchrotron Light Source II, a U.S. Department of Energy Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. H.D. and Y.Y. acknowledges funding support from the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (DE-EE0008234), UH Technical Gap Fund, and UH High Priority Area Large Equipment Grant.
Keywords
- 2D metal chalcogenides
- Conversion reaction
- In situ transmission electron microscopy
- Lithiation
- Lithium ion battery
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- General Materials Science
- Electrical and Electronic Engineering