Dissociation of CO2 to form CO can play a key role in decarbonizing our energy system. We report here a two-step thermochemical cycle using a variety of iron-poor (Fe-poor) ferrites (FeyM1-yOx where y < 2/3) that produce CO with unusually high yield using Fe as the redox active species. Conventional wisdom suggests that increasing the Fe fraction would increase the capacity for CO2 dissociation. Here, we report the opposite result: at partial pressure ratio CO : CO2 = 1 : 100, we demonstrated CO yields of 8.0 ± 1.0 mL-CO per gram from Fe0.35Ni0.65Ox, and 3.7 ± 1.0 mL-CO per gram from Fe0.45Co0.55Ox, at a thermal reduction temperature of 1300 °C; remarkably, these CO2 dissociation capacities are significantly higher than those of state-of-the-art materials such as spinel ferrites (Fe2MO4), (substituted) ceria, and Mn-based perovskite oxides. Optimization of the kinetics of Fe-poor ferrites with a ZrO2 support resulted in higher CO yields per gram of ferrite. The unexpected CO yield vs. Fe ratio trend is consistent with the prediction of calculated ternary phase diagrams, which suggest a swing between spinel and rocksalt phases. Finally, these Fe-poor ferrites open new opportunities for tuning the redox properties of oxygen exchange materials.
@article{osti_1608946,
author = {Zhai, Shang and Rojas, Jimmy and Ahlborg, Nadia and Lim, Kipil and Cheng, Chung Hon Michael and Xie, Chenlu and Toney, Michael F. and Jung, In-Ho and Chueh, William C. and Majumdar, Arun},
title = {High-capacity thermochemical CO<sub>2</sub> dissociation using iron-poor ferrites},
annote = {Dissociation of CO2 to form CO can play a key role in decarbonizing our energy system. We report here a two-step thermochemical cycle using a variety of iron-poor (Fe-poor) ferrites (FeyM1-yOx where y 2 dissociation. Here, we report the opposite result: at partial pressure ratio CO : CO2 = 1 : 100, we demonstrated CO yields of 8.0 ± 1.0 mL-CO per gram from Fe0.35Ni0.65Ox, and 3.7 ± 1.0 mL-CO per gram from Fe0.45Co0.55Ox, at a thermal reduction temperature of 1300 °C; remarkably, these CO2 dissociation capacities are significantly higher than those of state-of-the-art materials such as spinel ferrites (Fe2MO4), (substituted) ceria, and Mn-based perovskite oxides. Optimization of the kinetics of Fe-poor ferrites with a ZrO2 support resulted in higher CO yields per gram of ferrite. The unexpected CO yield vs. Fe ratio trend is consistent with the prediction of calculated ternary phase diagrams, which suggest a swing between spinel and rocksalt phases. Finally, these Fe-poor ferrites open new opportunities for tuning the redox properties of oxygen exchange materials.},
doi = {10.1039/c9ee02795e},
url = {https://www.osti.gov/biblio/1608946},
journal = {Energy & Environmental Science},
issn = {ISSN 1754-5692},
number = {2},
volume = {13},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2020},
month = {01}}
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Fuel Cell Technologies Office (EE-3F)
Grant/Contract Number:
AC02-76SF00515; AC02-76SF00515
OSTI ID:
1608946
Alternate ID(s):
OSTI ID: 1593476
Journal Information:
Energy & Environmental Science, Journal Name: Energy & Environmental Science Journal Issue: 2 Vol. 13; ISSN EESNBY; ISSN 1754-5692
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 368, Issue 1923https://doi.org/10.1098/rsta.2010.0119