Search NASA⌕ Search

DOE OSTI · 1757085

Materials Data on Ba5Lu8Ni4O21 by Materials Project

Abstract

Ba5Lu8Ni4O21 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.69–3.23 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are two shorter (2.83 Å) and eight longer (2.88 Å) Ba–O bond lengths. There are two inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with three LuO7 pentagonal bipyramids, corners with two equivalent NiO5 trigonal bipyramids, edges with three equivalent LuO7 pentagonal bipyramids, edges with two equivalent NiO5 trigonal bipyramids, and faces with two equivalent LuO7 pentagonal bipyramids. There are a spread of Lu–O bond distances ranging from 2.25–2.39 Å. In the second Lu3+ site, Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent LuO7 pentagonal bipyramids, corners with two equivalent NiO5 trigonal bipyramids, edges with five LuO7 pentagonal bipyramids, an edgeedge with one NiO5 trigonal bipyramid, and a faceface with one NiO5 trigonal bipyramid. There are a spread of Lu–O bond distances ranging from 2.23–2.37 Å. Ni2+ is bonded to five O2- atoms to form NiO5 trigonal bipyramids that share corners with four LuO7 pentagonal bipyramids, edges with three LuO7 pentagonal bipyramids, and a faceface with one LuO7 pentagonal bipyramid. There are a spread of Ni–O bond distances ranging from 2.01–2.08 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, three Lu3+, and one Ni2+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Lu3+, and one Ni2+ atom. In the third O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Lu3+ atoms to form distorted corner-sharing OBa2Lu4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to four equivalent Ba2+, one Lu3+, and one Ni2+ atom to form a mixture of distorted edge and corner-sharing OBa4LuNi octahedra. The corner-sharing octahedral tilt angles are 4°.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-09-03. Materials Data on Ba5Lu8Ni4O21 by Materials Project. https://doi.org/10.17188/1757085

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↗