Band diagram and rate analysis of thin film spinel LiMn2O4 formed by electrochemical conversion of ALD-grown MnO
- Univ. of Colorado, Boulder, CO (United States)
- Leupold-Institut fur Angewandte Naturwissenschaften, Zwickau (Germany)
- Univ. of Colorado, Boulder, CO (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
Nanoscale spinel lithium manganese oxide is of interest as a high-rate cathode material for advanced battery technologies among other electrochemical applications. In this work, the synthesis of ultrathin films of spinel lithium manganese oxide (LiMn2O4) between 20 and 200 nm in thickness by room-temperature electrochemical conversion of MnO grown by atomic layer deposition (ALD) is demonstrated. The charge storage properties of LiMn2O4 thin films in electrolytes containing Li+, Na+, K+, and Mg2+ are investigated. A unified electrochemical band-diagram (UEB) analysis of LiMn2O4 informed by screened hybrid density functional theory calculations is also employed to expand on existing understanding of the underpinnings of charge storage and stability in LiMn2O4. It is shown that the incorporation of Li+ or other cations into the host manganese dioxide spinel structure (λ-MnO2) stabilizes electronic states from the conduction band which align with the known redox potentials of LiMn2O4. Furthermore, the cyclic voltammetry experiments demonstrate that up to 30% of the capacity of LiMn2O4 arises from bulk electronic charge-switching which does not require compensating cation mass transport. As a result, the hybrid ALD-electrochemical synthesis, UEB analysis, and unique charge storage mechanism described here provide a fundamental framework to guide the development of future nanoscale electrode materials for ion-incorporation charge storage.
- Research Organization:
- National Renewable Energy Laboratory (NREL), Golden, CO (United States); Energy Frontier Research Centers (EFRC) (United States). Center for Next Generation of Materials by Design: Incorporating Metastability (CNGMD)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC36-08GO28308; AC36-99GO10337
- OSTI ID:
- 1333410
- Report Number(s):
- NREL/JA-5K00-67263
- Journal Information:
- Advanced Functional Materials, Vol. 26, Issue 43; ISSN 1616-301X
- Publisher:
- WileyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Synthesis, characterization and electrochemmistry of lithium battery electrodes : xLi{sub 2}MnO{sub 3}{center_dot}(1-x)LiMn{sub 0.333}Ni{sub 0.333}Co{sub 0.333}O{sub2} (0{le}x{le}0.7).
3D LiMn2O4nThin Film Deposited by ALD: A Road toward High-Capacity Electrode for 3D Li-Ion Microbatteries