Search NASA⌕ Search

DOE OSTI · 1688202

Materials Data on Ce2AlGaNi2 by Materials Project

Abstract

Ce2Ni2GaAl crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are six inequivalent Ce sites. In the first Ce site, Ce is bonded in a 5-coordinate geometry to five Ni, two equivalent Ga, and four Al atoms. There are a spread of Ce–Ni bond distances ranging from 2.87–2.94 Å. Both Ce–Ga bond lengths are 3.10 Å. There are two shorter (3.26 Å) and two longer (3.27 Å) Ce–Al bond lengths. In the second Ce site, Ce is bonded in a 11-coordinate geometry to five Ni, four Ga, and two equivalent Al atoms. There are four shorter (2.89 Å) and one longer (2.94 Å) Ce–Ni bond lengths. There are two shorter (3.10 Å) and two longer (3.24 Å) Ce–Ga bond lengths. Both Ce–Al bond lengths are 3.26 Å. In the third Ce site, Ce is bonded in a 11-coordinate geometry to five Ni, four Ga, and two equivalent Al atoms. There are a spread of Ce–Ni bond distances ranging from 2.87–2.96 Å. There are two shorter (3.10 Å) and two longer (3.24 Å) Ce–Ga bond lengths. Both Ce–Al bond lengths are 3.26 Å. In the fourth Ce site, Ce is bonded in a 5-coordinate geometry to five Ni, two equivalent Ga, and four Al atoms. There are a spread of Ce–Ni bond distances ranging from 2.87–2.92 Å. Both Ce–Ga bond lengths are 3.23 Å. There are two shorter (3.13 Å) and two longer (3.25 Å) Ce–Al bond lengths. In the fifth Ce site, Ce is bonded in a 5-coordinate geometry to five Ni, four Ga, and two equivalent Al atoms. There are four shorter (2.89 Å) and one longer (2.93 Å) Ce–Ni bond lengths. All Ce–Ga bond lengths are 3.23 Å. Both Ce–Al bond lengths are 3.13 Å. In the sixth Ce site, Ce is bonded in a 5-coordinate geometry to five Ni, two equivalent Ga, and four Al atoms. There are a spread of Ce–Ni bond distances ranging from 2.88–2.94 Å. Both Ce–Ga bond lengths are 3.24 Å. There are two shorter (3.13 Å) and two longer (3.24 Å) Ce–Al bond lengths. There are six inequivalent Ni sites. In the first Ni site, Ni is bonded in a 9-coordinate geometry to six Ce, two Ga, and one Al atom. There are one shorter (2.72 Å) and one longer (2.73 Å) Ni–Ga bond lengths. The Ni–Al bond length is 2.71 Å. In the second Ni site, Ni is bonded in a 9-coordinate geometry to six Ce, one Ga, and two Al atoms. The Ni–Ga bond length is 2.74 Å. Both Ni–Al bond lengths are 2.73 Å. In the third Ni site, Ni is bonded in a 9-coordinate geometry to six Ce, two Ga, and one Al atom. There are one shorter (2.72 Å) and one longer (2.73 Å) Ni–Ga bond lengths. The Ni–Al bond length is 2.72 Å. In the fourth Ni site, Ni is bonded in a 9-coordinate geometry to six Ce, one Ga, and two Al atoms. The Ni–Ga bond length is 2.74 Å. There are one shorter (2.72 Å) and one longer (2.73 Å) Ni–Al bond lengths. In the fifth Ni site, Ni is bonded in a 9-coordinate geometry to three Ce, two equivalent Ga, and four Al atoms. Both Ni–Ga bond lengths are 2.60 Å. All Ni–Al bond lengths are 2.56 Å. In the sixth Ni site, Ni is bonded in a 9-coordinate geometry to three Ce, four Ga, and two equivalent Al atoms. All Ni–Ga bond lengths are 2.59 Å. Both Ni–Al bond lengths are 2.55 Å. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded to six Ce, four Ni, one Ga, and one Al atom to form distorted GaCe6AlGaNi4 cuboctahedra that share corners with two equivalent GaCe6AlGaNi4 cuboctahedra, corners with two equivalent AlCe6Ga2Ni4 cuboctahedra, edges with two equivalent GaCe6AlGaNi4 cuboctahedra, edges with two equivalent AlCe6Ga2Ni4 cuboctahedra, faces with two equivalent AlCe6Ga2Ni4 cuboctahedra, and faces with four GaCe6AlGaNi4 cuboctahedra. The Ga–Ga bond length is 2.82 Å. The Ga–Al bond length is 2.78 Å. In the second Ga site, Ga is bonded to six Ce, four Ni, and two Al atoms to form GaCe6Al2Ni4 cuboctahedra that share corners with two equivalent GaCe6AlGaNi4 cuboctahedra, corners with two equivalent AlCe6Ga2Ni4 cuboctahedra, a faceface with one AlCe6Ga2Ni4 cuboctahedra, and faces with three GaCe6Al2Ni4 cuboctahedra. There are one shorter (2.78 Å) and one longer (2.79 Å) Ga–Al bond lengths. In the third Ga site, Ga is bonded to six Ce, four Ni, one Ga, and one Al atom to form distorted GaCe6AlGaNi4 cuboctahedra that share corners with four GaCe6AlGaNi4 cuboctahedra, edges with two equivalent GaCe6AlGaNi4 cuboctahedra, edges with two equivalent AlCe6Ga2Ni4 cuboctahedra, a faceface with one AlCe6Ga2Ni4 cuboctahedra, and faces with five GaCe6AlGaNi4 cuboctahedra. The Ga–Al bond length is 2.77 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to six Ce, four Ni, one Ga, and one Al atom. The Al–Al bond length is 2.77 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to six Ce, four Ni, one Ga, and one Al atom. In the third Al site, Al is bonded to six Ce, four Ni, and two Ga atoms to form distorted AlCe6Ga2Ni4 cuboctahedra that share corners with four GaCe6AlGaNi4 cuboctahedra, edges with four GaCe6AlGaNi4 cuboctahedra, faces with two equivalent AlCe6Ga2Ni4 cuboctahedra, and faces with four GaCe6AlGaNi4 cuboctahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-03. Materials Data on Ce2AlGaNi2 by Materials Project. https://doi.org/10.17188/1688202

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↗