Nanostructured LiMnO2 with Li3PO4 Integrated at the Atomic Scale for High-Energy Electrode Materials with Reversible Anionic Redox

Cited 1 time in webofscience Cited 0 time in scopus
  • Hit : 66
  • Download : 14
Nanostructured LiMnO2, integrated with Li3PO4 was successfully synthesized by the mechanical milling route and examined as a new series of positive electrode materials for rechargeable lithium batteries. Although uniform mixing at the atomic scale between LiMnO2 and Li3PO4 was not anticipated because of the noncompatibility of crystal structures for both phases, our study reveals that phosphorus ions with excess lithium ions dissolve into nanosize crystalline LiMnO2 as first evidenced by elemental mapping using STEM-EELS combined with total X-ray scattering, solid-state NMR spectroscopy, and a theoretical ab initio study. The integrated phase features a low-crystallinity metastable phase with a unique nanostructure; the phosphorus ion located at the tetrahedral site shares faces with adjacent lithium ions at slightly distorted octahedral sites. This phase delivers a large reversible capacity of similar to 320 mA h g(-1) as a high-energy positive electrode material in Li cells. The large reversible capacity originated from the contribution from the anionic redox of oxygen coupled with the cationic redox of Mn ions, as evidenced by operando soft XAS spectroscopy, and the superior reversibility of the anionic redox and the suppression of oxygen loss were also found by online electrochemical mass spectroscopy. The improved reversibility of the anionic redox originates from the presence of phosphorus ions associated with the suppression of oxygen dimerization, as supported by a theoretical study. From these results, the mechanistic foundations of nanostructured high-capacity positive electrode materials were established, and further chemical and physical optimization may lead to the development of next-generation electrochemical devices.
Publisher
AMER CHEMICAL SOC
Issue Date
2020-12
Language
English
Article Type
Article
Citation

ACS CENTRAL SCIENCE, v.6, no.12, pp.2326 - 2338

ISSN
2374-7943
DOI
10.1021/acscentsci.0c01200
URI
http://hdl.handle.net/10203/280060
Appears in Collection
CH-Journal Papers(저널논문)
Files in This Item
117726.pdf(10.36 MB)Download
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡ Click to see webofscience_button
⊙ Cited 1 items in WoS Click to see citing articles in records_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0