@article{1e80fec1e3434a5f99de600906cb5f27,
title = "Superstoichiometric Alloying of H and Close-Packed Fe-Ni Metal Under High Pressures: Implications for Hydrogen Storage in Planetary Core",
abstract = "Although high pressure enables alloying between hydrogen and iron, hydrogen-to-iron molar ratio (H/Fe) so far found in experiments is mostly limited to 1 in the close-packed iron metal under high pressure. We report a H/(Fe + Ni) ratio of 1.8 ± 0.1 from (Fe,Ni)Hx (or x ≥ 1.8) quenched from liquid, exceeding the amounts so far reported for densely packed Fe alloys. From the metastable behavior of the frozen (Fe,Ni)Hx liquid during decompression, we infer that the amount is a lower bound and therefore even a greater amount of H can be dissolved in the liquid part of Fe-rich cores of planets. The significant H storage capacity of liquid Fe-Ni alloy is important to consider for potential storage of H in the interiors of low-density planets as well as rocky planets.",
keywords = "alloy, core, hydrogen, iron",
author = "H{\'e}l{\`e}ne Piet and Andrew Chizmeshya and Bin Chen and Stella Chariton and Eran Greenberg and Vitali Prakapenka and Peter Buseck and Shim, {Sang Heon}",
note = "Funding Information: We thank six anonymous reviewers for their helpful comments. The work has been supported by the NASA (80NSSC18K0353) and NSF (EAR1921298 and AST2005567). H.P., P.B., and S.-H.S. were supported partially by the Keck Foundation (PI: P. Buseck). The results reported herein benefit from collaborations and information exchange within NASA's Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA's Science Mission Directorate. A.V.G.C. gratefully acknowledges ASU's supercomputing resources. B.C. acknowledges the support from NSF (EAR-1555388, EAR-1829273). The synchrotron experiments were conducted at GeoSoilEnviroCARS (University of Chicago, Sector 13), Advanced Photon Source (APS). GeoSoilEnviroCARS is supported by the NSF-Earth Science (EAR-1634415) and DOE-GeoScience (DE-FG02-94ER14466). APS is supported by DOE-BES under contract DE-AC02-06CH11357. Funding Information: We thank six anonymous reviewers for their helpful comments. The work has been supported by the NASA (80NSSC18K0353) and NSF (EAR1921298 and AST2005567). H.P., P.B., and S.‐H.S. were supported partially by the Keck Foundation (PI: P. Buseck). The results reported herein benefit from collaborations and information exchange within NASA's Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA's Science Mission Directorate. A.V.G.C. gratefully acknowledges ASU's supercomputing resources. B.C. acknowledges the support from NSF (EAR‐1555388, EAR‐1829273). The synchrotron experiments were conducted at GeoSoilEnviroCARS (University of Chicago, Sector 13), Advanced Photon Source (APS). GeoSoilEnviroCARS is supported by the NSF‐Earth Science (EAR‐1634415) and DOE‐GeoScience (DE‐FG02‐94ER14466). APS is supported by DOE‐BES under contract DE‐AC02‐06CH11357. Publisher Copyright: {\textcopyright} 2023. The Authors.",
year = "2023",
month = mar,
day = "16",
doi = "10.1029/2022GL101155",
language = "English (US)",
volume = "50",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "5",
}