In Situ AFM Imaging of Li-O-2 Electrochemical Reaction on Highly Oriented Pyrolytic Graphite with Ether-Based Electrolyte

Cited 101 time in webofscience Cited 92 time in scopus
  • Hit : 334
  • Download : 0
Understanding the lithium oxygen (Li-O-2) electrochemical reaction is of importance to improve reaction kinetics, efficiency, and mitigate parasitic reactions, which links to the strategy of enhanced Li-O-2 battery performance. Many in situ and ex situ analyses have been reported to address chemical species of reduction intermediate and products, whereas details of the dynamic Li-O-2 reaction have not as yet been fully unraveled. For this purpose, visual imaging can provide straightforward evidence, formation and decomposition of products, during the Li-O-2 electrochemical reaction. Here, we present real-time and in situ views of the Li-O-2 reaction using electrochemical atomic force microscopy (EC-AFM). Details of the reaction process can be observed at nano-/micrometer scale on a highly oriented pyrolytic graphite (HOPG) electrode with lithium ion-containing tetraglyme, representative of the carbon cathode and ether-based electrolyte extensively employed in the Li-O-2 battery. Upon oxygen reduction reaction (ORR), rapid growth of nanoplates, having axial diameter of hundreds of nanometers, length of micrometers, and similar to 5 nm thickness, at a step edge of HOPG can be observed, which eventually forms a lithium peroxide (Li2O2) film. This Li2O2 film is decomposed during the oxygen evolution reaction (OER), for which the decomposition potential is related to a thickness. There is no evidence of byproduct analyzed by X-ray photoelectron spectroscopy (XPS) after first reduction and oxidation reaction. However, further cycles provide unintended products such as lithium carbonate (Li2CO2), lithium acetate, and fluorine-related species with irregular morphology due to the degradation of HOPG electrode, tetraglyme, and lithium salt. These observations provide the first visualization of Li-O-2 reaction process and morphological information of Li2O2, which can allow one to build strategies to prepare the optimum conditions for the Li-O-2 battery.
Publisher
AMER CHEMICAL SOC
Issue Date
2013-07
Language
English
Article Type
Article
Keywords

LI-AIR BATTERIES; LITHIUM-OXYGEN BATTERY; KINETIC OVERPOTENTIALS; SPECTROSCOPY; PERFORMANCE; CHALLENGES; STABILITY; CATALYSTS; PRODUCTS; SOLVENTS

Citation

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, v.135, no.29, pp.10870 - 10876

ISSN
0002-7863
DOI
10.1021/ja405188g
URI
http://hdl.handle.net/10203/207225
Appears in Collection
CH-Journal Papers(저널논문)
Files in This Item
There are no files associated with this item.
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡ Click to see webofscience_button
⊙ Cited 101 items in WoS Click to see citing articles in records_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0