Search NASA⌕ Search

DOE OSTI · 1672689

Materials Data on LuGaNi2 by Materials Project

Abstract

LuNi2Ga is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are three inequivalent Lu sites. In the first Lu site, Lu is bonded in a 12-coordinate geometry to three equivalent Ni and nine equivalent Ga atoms. All Lu–Ni bond lengths are 2.99 Å. There are six shorter (2.98 Å) and three longer (3.02 Å) Lu–Ga bond lengths. In the second Lu site, Lu is bonded in a 12-coordinate geometry to twelve Ni atoms. There are six shorter (2.89 Å) and six longer (3.01 Å) Lu–Ni bond lengths. In the third Lu site, Lu is bonded in a 6-coordinate geometry to twelve Ni and six equivalent Ga atoms. There are six shorter (2.94 Å) and six longer (3.18 Å) Lu–Ni bond lengths. All Lu–Ga bond lengths are 3.27 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Lu, three equivalent Ni, and three equivalent Ga atoms. All Ni–Ni bond lengths are 2.44 Å. All Ni–Ga bond lengths are 2.47 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Lu, three equivalent Ni, and three equivalent Ga atoms. All Ni–Ni bond lengths are 2.47 Å. All Ni–Ga bond lengths are 2.46 Å. In the third Ni site, Ni is bonded to six equivalent Lu and six equivalent Ni atoms to form NiLu6Ni6 cuboctahedra that share corners with twelve equivalent NiLu5Ni7 cuboctahedra, edges with six equivalent NiLu6Ni6 cuboctahedra, and faces with eighteen equivalent NiLu5Ni7 cuboctahedra. All Ni–Ni bond lengths are 2.48 Å. In the fourth Ni site, Ni is bonded to six equivalent Lu and six equivalent Ga atoms to form NiLu6Ga6 cuboctahedra that share corners with twelve equivalent GaLu5Ga4Ni3 cuboctahedra, edges with six equivalent NiLu6Ga6 cuboctahedra, and faces with eighteen equivalent GaLu5Ga4Ni3 cuboctahedra. All Ni–Ga bond lengths are 2.57 Å. In the fifth Ni site, Ni is bonded to five Lu and seven Ni atoms to form NiLu5Ni7 cuboctahedra that share corners with six equivalent GaLu5Ga4Ni3 cuboctahedra, corners with eleven NiLu6Ni6 cuboctahedra, edges with four equivalent NiLu5Ni7 cuboctahedra, edges with four equivalent GaLu5Ga4Ni3 cuboctahedra, a faceface with one GaLu5Ga4Ni3 cuboctahedra, and faces with thirteen NiLu6Ni6 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.56 Å) Ni–Ni bond lengths. Ga is bonded to five Lu, three Ni, and four equivalent Ga atoms to form distorted GaLu5Ga4Ni3 cuboctahedra that share corners with eight NiLu6Ga6 cuboctahedra, corners with nine equivalent GaLu5Ga4Ni3 cuboctahedra, edges with four equivalent NiLu5Ni7 cuboctahedra, edges with four equivalent GaLu5Ga4Ni3 cuboctahedra, faces with four NiLu6Ga6 cuboctahedra, and faces with ten equivalent GaLu5Ga4Ni3 cuboctahedra. There are two shorter (2.54 Å) and two longer (2.56 Å) Ga–Ga bond lengths.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-29. Materials Data on LuGaNi2 by Materials Project. https://doi.org/10.17188/1672689

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↗