Engineering Papers⌕ Search

DOE OSTI · 1191237

Materials Data on Li3GaF6 by Materials Project

Abstract

Li3GaF6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are five inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.93–2.46 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.93–2.55 Å. In the third Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with two equivalent GaF6 octahedra, corners with two equivalent LiF4 tetrahedra, and edges with two equivalent GaF6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Li–F bond distances ranging from 2.02–2.13 Å. In the fourth Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share a cornercorner with one LiF6 octahedra, corners with four GaF6 octahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–65°. There are a spread of Li–F bond distances ranging from 1.88–1.92 Å. In the fifth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of Li–F bond distances ranging from 1.89–2.19 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six F1- atoms to form GaF6 octahedra that share a cornercorner with one LiF6 octahedra and corners with three equivalent LiF4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Ga–F bond distances ranging from 1.91–1.96 Å. In the second Ga3+ site, Ga3+ is bonded to six F1- atoms to form GaF6 octahedra that share corners with two equivalent LiF4 tetrahedra and edges with two equivalent LiF6 octahedra. There are a spread of Ga–F bond distances ranging from 1.90–1.94 Å. There are nine inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Ga3+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Ga3+ atom. In the third F1- site, F1- is bonded in a distorted rectangular see-saw-like geometry to three Li1+ and one Ga3+ atom. In the fourth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Ga3+ atom. In the fifth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Ga3+ atom. In the sixth F1- site, F1- is bonded to three Li1+ and one Ga3+ atom to form distorted corner-sharing FLi3Ga tetrahedra. In the seventh F1- site, F1- is bonded to three Li1+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing FLi3Ga trigonal pyramids. In the eighth F1- site, F1- is bonded to three Li1+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing FLi3Ga tetrahedra. In the ninth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Ga3+ atom.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-01. Materials Data on Li3GaF6 by Materials Project. https://doi.org/10.17188/1191237

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↗