Search NASA⌕ Search

DOE OSTI · 1757036

Materials Data on ThFe4Co by Materials Project

Abstract

ThFe4Co crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Th is bonded in a 6-coordinate geometry to fifteen Fe and three equivalent Co atoms. There are a spread of Th–Fe bond distances ranging from 2.92–3.25 Å. There are one shorter (2.92 Å) and two longer (2.93 Å) Th–Co bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to three equivalent Th, six Fe, and three equivalent Co atoms to form distorted FeTh3Fe6Co3 cuboctahedra that share corners with nine equivalent CoTh3Fe9 cuboctahedra, corners with twelve FeTh4Fe6Co2 cuboctahedra, edges with six equivalent FeTh3Fe6Co3 cuboctahedra, faces with three equivalent CoTh3Fe9 cuboctahedra, and faces with twenty FeTh3Fe6Co3 cuboctahedra. All Fe–Fe bond lengths are 2.50 Å. There are one shorter (2.92 Å) and two longer (2.93 Å) Fe–Co bond lengths. In the second Fe site, Fe is bonded to four equivalent Th, six Fe, and two equivalent Co atoms to form FeTh4Fe6Co2 cuboctahedra that share corners with four equivalent CoTh3Fe9 cuboctahedra, corners with twenty FeTh3Fe6Co3 cuboctahedra, edges with ten FeTh4Fe6Co2 cuboctahedra, faces with six equivalent CoTh3Fe9 cuboctahedra, and faces with sixteen FeTh3Fe6Co3 cuboctahedra. There are three shorter (2.53 Å) and one longer (2.54 Å) Fe–Fe bond lengths. Both Fe–Co bond lengths are 2.50 Å. In the third Fe site, Fe is bonded to four equivalent Th, six Fe, and two equivalent Co atoms to form distorted FeTh4Fe6Co2 cuboctahedra that share corners with four equivalent CoTh3Fe9 cuboctahedra, corners with twenty FeTh4Fe6Co2 cuboctahedra, edges with ten FeTh4Fe6Co2 cuboctahedra, faces with six equivalent CoTh3Fe9 cuboctahedra, and faces with sixteen FeTh3Fe6Co3 cuboctahedra. Both Fe–Co bond lengths are 2.50 Å. Co is bonded to three equivalent Th and nine Fe atoms to form distorted CoTh3Fe9 cuboctahedra that share corners with twenty-one FeTh3Fe6Co3 cuboctahedra, edges with six equivalent CoTh3Fe9 cuboctahedra, faces with two equivalent CoTh3Fe9 cuboctahedra, and faces with twenty-one FeTh3Fe6Co3 cuboctahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-09-03. Materials Data on ThFe4Co by Materials Project. https://doi.org/10.17188/1757036

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related reports

Cyclic moisture reactivation of calcium sorbents for long duration thermochemical energy storage

The transition to a flexible and reliable energy infrastructure, using electro-thermal energy generation technologies such as geothermal, concentrated solar power, and nuclear, usually demands simultaneous advancement of thermal energy storage (TES) to support on-demand electricity generation and industrial applications while mitigating the inherent intermittency of renewable energy sources and power outages from direct energy generation. Among TES technologies, thermochemical energy storage (TCES) based on calcium looping emerges as a compelling high-power energy storage candidate due to its high reaction enthalpy, compatibility with elevated operating temperatures, and abundance of low-cost materials. However, the long-term durability of calcium-based sorbents for TCES is hindered by surface sintering and particle aggregation, leading to performance degradation over repeated thermal cycles. This study explores a moisture hydration-based strategy to regenerate a degraded calcium sorbent and mitigate performance degradation for long duration TCES. The addition of moisture transforms calcium oxide into calcium hydroxide and produces intercalation water layers, associated with a regenerated surface area and reduced calcium oxide crystallite size. Both these effects are beneficial in restoring the sorbents' reactivity for carbonization. Additionally, an optimized hydration-assisted reactivation protocol balances the recovered energy storage capacity with heating penalty required for moisture removal from hydrated samples, resulting in an enhanced energy storage capacity up to 176% compared to benchmark sorbents that undergo cycling without reactivation after 60 cycles. In conclusion, these results highlight the potential of hydration-assisted reactivation to enhance the long-term performance of TCES, providing an effective pathway to advancing electro-thermal storage technologies.

36 MATERIALS SCIENCE↗