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Title: A Kinetic Study on H 2 Reduction of Fe 3 O 4 for Long-Duration Energy-Storage-Compatible Solid Oxide Iron Air Batteries
Long duration energy storage (LDES) is economically attractive to accelerate widespread renewable energy deployment. But none of the existing energy storage technologies can meet LDES cost requirements. The newly emerged solid oxide iron air battery (SOIAB) with energy-dense solid Fe as an energy storage material is a competitive LDES-suitable technology compared to conventional counterparts. However, the performance of SOIAB is critically limited by the kinetics of Fe3O4reduction (equivalent to charging process) and the understanding of this kinetic bottleneck is significantly lacking in the literature. Here, we report a systematic kinetic study of Fe3O4-to-Fe reduction in H2/H2O environment, particularly the effect of catalyst (iridium) and supporting oxides (ZrO2and BaZr0.4Ce0.4Y0.1Yb0.1O3). With in situ created Fe3O4, the degree of reduction is measured by the change of H2O and H2concentrations in the effluent using a mass spectrometer, from which the kinetic rate constant is extracted as a function of inlet H2concentration and temperature. We find that kinetics can be nicely described by Johson-Mehl-Avrami (JMA) model. We also discuss the stepwise reduction mechanisms and activation energy for the reduction process.  more » « less
Award ID(s):
1801284
PAR ID:
10474619
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP science
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
170
Issue:
10
ISSN:
0013-4651
Page Range / eLocation ID:
104504
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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