Search NASA⌕ Search

DOE OSTI · 1749477

Materials Data on LiMg14BO15 by Materials Project

Abstract

LiMg14BO15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Li is bonded to five O atoms to form LiO5 square pyramids that share corners with two equivalent MgO6 octahedra, corners with two equivalent LiO5 square pyramids, corners with two equivalent MgO5 square pyramids, and edges with eight MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Li–O bond distances ranging from 2.13–2.27 Å. There are ten inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent LiO5 square pyramids, edges with ten MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 4°. There are a spread of Mg–O bond distances ranging from 1.97–2.28 Å. In the second Mg site, Mg is bonded in a T-shaped geometry to three O atoms. There are one shorter (2.02 Å) and two longer (2.14 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with seven MgO6 octahedra, edges with two equivalent LiO5 square pyramids, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of Mg–O bond distances ranging from 2.05–2.18 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with five MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–28°. There are a spread of Mg–O bond distances ranging from 1.98–2.23 Å. In the fifth Mg site, Mg is bonded in a square co-planar geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 2.10–2.17 Å. In the sixth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, edges with six MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Mg–O bond distances ranging from 2.09–2.28 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, edges with eight MgO6 octahedra, and edges with two equivalent LiO5 square pyramids. The corner-sharing octahedra tilt angles range from 2–12°. There are a spread of Mg–O bond distances ranging from 2.09–2.17 Å. In the eighth Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. In the ninth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with two equivalent MgO6 octahedra, a cornercorner with one LiO5 square pyramid, corners with three equivalent MgO5 square pyramids, and edges with seven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–32°. There are a spread of Mg–O bond distances ranging from 1.98–2.34 Å. In the tenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with nine MgO6 octahedra, and an edgeedge with one LiO5 square pyramid. The corner-sharing octahedra tilt angles range from 6–15°. There are a spread of Mg–O bond distances ranging from 2.04–2.26 Å. B is bonded in a 3-coordinate geometry to five O atoms. There are a spread of B–O bond distances ranging from 1.49–2.18 Å. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with three OMg5B octahedra, corners with two equivalent OMg5 square pyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–84°. In the second O site, O is bonded to one Li and five Mg atoms to form OLiMg5 octahedra that share corners with four OLiMg5 octahedra and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 12–13°. In the third O site, O is bonded to five Mg and one B atom to form distorted OMg5B octahedra that share corners with four OLiMg5 octahedra, a cornercorner with one OMg5 square pyramid, and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 8–13°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra, edges with six OLi2Mg4 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–8°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with ten OLiMg5 octahedra. The corner-sharing octahedra tilt angles range from 2–7°. In the sixth O site, O is bonded to two equivalent Li and four Mg atoms to form a mixture of corner and edge-sharing OLi2Mg4 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra, edges with ten OMg5B octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–4°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with six OLiMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the ninth O site, O is bonded to four Mg and two equivalent B atoms to form distorted OMg4B2 octahedra that share corners with six OMg6 octahedra, corners with two equivalent OMg5 square pyramids, and edges with six OMg5B octahedra. The corner-sharing octahedra tilt angles range from 0–21°. In the tenth O site, O is bonded to one Li and five Mg atoms to form OLiMg5 octahedra that share corners with four equivalent OLiMg5 octahedra, edges with ten OLiMg5 octahedra, and an edgeedge with one OMg5 square pyramid. The corner-sharing octahedra tilt angles range from 2–5°. In the eleventh O site, O is bonded in a 1-coordinate geometry to four Mg and one B atom.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-01. Materials Data on LiMg14BO15 by Materials Project. https://doi.org/10.17188/1749477

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↗