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Title: Effect of Soluble Corrosion Products on Electrical Double Layer in LiCl-KCl Molten Salts
Corrosion in molten salts greatly hampers the application for renewable energy applications like molten salt reactors. To develop effective strategies for corrosion mitigation, understanding the interfacial structures and properties such as specific ion adsorption and electrical double layer capacitance are crucial. Using cyclic voltammetry and electrochemical impedance spectroscopy, we systematically studied the interfaces on various model electrodes including W (solid), Bi (liquid), and the stainless steel 316 in LiCl-KCl eutectic molten salts with the addition of corrosion species CrCl2and FeCl2. Both Cr2+and Fe2+ions increased electrical double layer capacitance, with Cr2+showing specific adsorption behavior and shifting the potential of zero charge, while Fe2+had minimal effect on point of zero charge. Two-working electrode measurements revealed increasing open-circuit potential and electrical double layer capacitance during the exposure of stainless steel 316, indicating its progressive corrosion and ion accumulation at the interface. X-ray photoelectron spectroscopy and Raman confirmed Cr enrichment at the interface. This work highlights the strong correlation between electrical double layer behavior and corrosion dynamics in molten salts and suggests electrical double layer capacitance as a sensitive, in situ indicator for corrosion monitoring.  more » « less
Award ID(s):
2239690
PAR ID:
10661437
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ECS
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
172
Issue:
11
ISSN:
0013-4651
Page Range / eLocation ID:
111502
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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