In:
Journal of Materials Chemistry A, Royal Society of Chemistry (RSC), Vol. 10, No. 38 ( 2022), p. 20294-20301
Abstract:
Lithium superoxide (LiO 2 ), which is considered to be an unstable intermediate, was shown recently to be a stable discharge product in lithium oxygen batteries (LOBs). As such, the in situ observation of LiO 2 dynamics may provide direct evidence for the working mechanism of LOBs. Here we report in situ imaging of the nucleation, growth and stabilization of LiO 2 in LOBs with Au nanoparticle coated carbon nanotubes as an air cathode by aberration corrected environmental transmission electron microscopy. During discharge, LiO 2 spheres nucleated and grew from aggregated Li–Au alloy (Li 15 Au 4 ) nanoparticle seeds and were stable for several minutes. Density functional theory calculations suggest that the de-activation of lithium via electron transfer from Li to Au and O weakens Li's electron donation capability and prevents the dissolution of superoxide-like species, which favors a one electron transfer oxygen reduction reaction, thus facilitating the nucleation and stabilization of LiO 2 . The lithium de-activation induced LiO 2 dynamics advances our understanding of LiO 2 mediated solid-state LOBs and may provide a new strategy for the design of LOBs.
Type of Medium:
Online Resource
ISSN:
2050-7488
,
2050-7496
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
detail.hit.zdb_id:
2702232-8
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