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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Spin-Selective Oxygen Evolution Reaction in Chiral Iron Oxide Nanoparticles: Synergistic Impact of Inherent Magnetic Moment and Chirality

Electron spin polarization is identified as a promising avenue for enhancing the oxygen evolution reaction (OER), which is the bottleneck that limits the energy efficiency of water-splitting. Here, in this work, we report that both ferrimagnetic (f-Fe 3 O 4 ) and superparamagnetic iron oxide (s-Fe 3 O 4 ) catalysts can exhibit external magnetic field (Hext)-induced OER enhancement, and the activity is proportional to their intrinsic magnetic moment. Additionally, the chirality-induced spin selectivity (CISS) effect was utilized in synergy with Hext to get a maximum enhancement of up to 89% improvement in current density (at 1.8 V vs RHE) with a low onset potential of 270 mV in s-Fe 3 O 4 catalysts. Spin polarization and the resultant spin selectivity suppress the production of H 2 O 2 and promote the formation of ground state triplet O 2 during the OER. Furthermore, the design of chiral s-Fe 3 O 4 with synergistic spin potential effect demonstrates a high spin polarization of ∼42%, as measured using conductive atomic force microscopy (c-AFM).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on FeF2 by Materials Project

FeF2 is Hydrophilite structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Fe2+ is bonded to six equivalent F1- atoms to form a mixture of corner and edge-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two shorter (2.04 Å) and four longer (2.15 Å) Fe–F bond lengths. F1- is bonded in a distorted trigonal planar geometry to three equivalent Fe2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeF3 by Materials Project

FeF3 is alpha Rhenium trioxide structured and crystallizes in the trigonal P321 space group. The structure is three-dimensional. there are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. All Fe–F bond lengths are 1.95 Å. In the second Fe3+ site, Fe3+ is bonded to six equivalent F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Fe–F bond lengths are 1.95 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to two Fe3+ atoms. In the second F1- site, F1- is bonded in a linear geometry to two equivalent Fe3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeF4 by Materials Project

FeF4 is alpha Po structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two tetrafluoroiron molecules. Fe is bonded in a square co-planar geometry to four F atoms. There is two shorter (1.76 Å) and two longer (1.77 Å) Fe–F bond length. There are four inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Fe atom. In the second F site, F is bonded in a single-bond geometry to one Fe atom. In the third F site, F is bonded in a single-bond geometry to one Fe atom. In the fourth F site, F is bonded in a single-bond geometry to one Fe atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeF3 by Materials Project

FeF3 crystallizes in the trigonal P321 space group. The structure is three-dimensional. there are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedra tilt angles range from 24–34°. There is three shorter (1.96 Å) and three longer (1.97 Å) Fe–F bond length. In the second Fe3+ site, Fe3+ is bonded to six equivalent F1- atoms to form distorted corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 24°. All Fe–F bond lengths are 1.97 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to two Fe3+ atoms. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Fe3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeF3 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗