Search NASA⌕ Search

DOE OSTI · 1745267

Materials Data on GdAlNi4 by Materials Project

Abstract

GdNi4Al crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Gd is bonded in a 6-coordinate geometry to fifteen Ni and three equivalent Al atoms. There are a spread of Gd–Ni bond distances ranging from 2.88–3.14 Å. There are one shorter (2.88 Å) and two longer (2.89 Å) Gd–Al bond lengths. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Gd, six Ni, and three equivalent Al atoms to form NiGd3Al3Ni6 cuboctahedra that share corners with nine equivalent AlGd3Ni9 cuboctahedra, corners with twelve NiGd4Al2Ni6 cuboctahedra, edges with six equivalent NiGd3Al3Ni6 cuboctahedra, faces with three equivalent AlGd3Ni9 cuboctahedra, and faces with twenty NiGd3Al3Ni6 cuboctahedra. All Ni–Ni bond lengths are 2.37 Å. There are one shorter (2.88 Å) and two longer (2.89 Å) Ni–Al bond lengths. In the second Ni site, Ni is bonded to four equivalent Gd, six Ni, and two equivalent Al atoms to form distorted NiGd4Al2Ni6 cuboctahedra that share corners with four equivalent AlGd3Ni9 cuboctahedra, corners with twenty NiGd3Al3Ni6 cuboctahedra, edges with ten NiGd4Al2Ni6 cuboctahedra, faces with six equivalent AlGd3Ni9 cuboctahedra, and faces with sixteen NiGd3Al3Ni6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.47–2.54 Å. Both Ni–Al bond lengths are 2.39 Å. In the third Ni site, Ni is bonded to four equivalent Gd, six Ni, and two equivalent Al atoms to form distorted NiGd4Al2Ni6 cuboctahedra that share corners with four equivalent AlGd3Ni9 cuboctahedra, corners with twenty NiGd3Al3Ni6 cuboctahedra, edges with ten NiGd4Al2Ni6 cuboctahedra, faces with six equivalent AlGd3Ni9 cuboctahedra, and faces with sixteen NiGd3Al3Ni6 cuboctahedra. Both Ni–Al bond lengths are 2.39 Å. Al is bonded to three equivalent Gd and nine Ni atoms to form distorted AlGd3Ni9 cuboctahedra that share corners with twenty-one NiGd3Al3Ni6 cuboctahedra, edges with six equivalent AlGd3Ni9 cuboctahedra, faces with two equivalent AlGd3Ni9 cuboctahedra, and faces with twenty-one NiGd3Al3Ni6 cuboctahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-03. Materials Data on GdAlNi4 by Materials Project. https://doi.org/10.17188/1745267

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↗