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Title: Imaging Cycle-Induced Damage of MnO 2 Microparticles
MnO 2 has been proposed as an electrode material in electrochemical energy storage devices. However, poor cycle life, especially in aqueous electrolytes, remains a detriment to commercialization. Prior studies have suggested a number of explanations for this capacity loss; however, experiments aimed at elucidating the details of the degradation process (es) are sparse. We describe here a microtube-membrane construct that allows for electrodeposition of monodisperse MnO 2 microparticles distributed across the membrane surface, and for subsequent electrochemical cycling of these MnO 2 particles. This allowed for a detailed analysis of the effect of cycling on the MnO 2 , by simply imaging the membrane surface before and after cycling. When an aqueous electrolyte was used, gross changes in particle shape, size and morphology were observed over the course of 500 cycles. Partial dissolution occurred as well. No such changes were observed when the MnO 2 particles were cycled (up to 500 times) in a propylene carbonate electrolyte solution.  more » « less
Award ID(s):
1659782
PAR ID:
10454865
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
167
Issue:
13
ISSN:
0013-4651
Page Range / eLocation ID:
132501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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