Engineering Papers⌕ Search

DOE OSTI · 1758673

Materials Data on Ce2Co7 by Materials Project

Abstract

Ce2Co7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Ce sites. In the first Ce site, Ce is bonded in a 12-coordinate geometry to twelve Co atoms. There are a spread of Ce–Co bond distances ranging from 2.83–3.18 Å. In the second Ce site, Ce is bonded in a 6-coordinate geometry to eighteen Co atoms. There are a spread of Ce–Co bond distances ranging from 2.82–3.25 Å. There are seven inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to three equivalent Ce and nine Co atoms. There are a spread of Co–Co bond distances ranging from 2.44–2.85 Å. In the second Co site, Co is bonded in a 12-coordinate geometry to three equivalent Ce and nine Co atoms. There are a spread of Co–Co bond distances ranging from 2.41–2.51 Å. In the third Co site, Co is bonded to six equivalent Ce and six Co atoms to form CoCe6Co6 cuboctahedra that share corners with twelve CoCe5Co7 cuboctahedra, edges with six equivalent CoCe6Co6 cuboctahedra, and faces with eighteen CoCe5Co7 cuboctahedra. There are two shorter (2.55 Å) and four longer (2.56 Å) Co–Co bond lengths. In the fourth Co site, Co is bonded to four equivalent Ce and eight Co atoms to form CoCe4Co8 cuboctahedra that share corners with sixteen CoCe4Co8 cuboctahedra, edges with ten CoCe5Co7 cuboctahedra, and faces with ten CoCe4Co8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.43–2.46 Å. In the fifth Co site, Co is bonded to four equivalent Ce and eight Co atoms to form CoCe4Co8 cuboctahedra that share corners with sixteen CoCe4Co8 cuboctahedra, edges with ten CoCe5Co7 cuboctahedra, and faces with ten CoCe4Co8 cuboctahedra. In the sixth Co site, Co is bonded to five Ce and seven Co atoms to form distorted CoCe5Co7 cuboctahedra that share corners with seventeen CoCe6Co6 cuboctahedra, edges with eight CoCe5Co7 cuboctahedra, and faces with fourteen CoCe6Co6 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.43–2.47 Å. In the seventh Co site, Co is bonded to five Ce and seven Co atoms to form distorted CoCe5Co7 cuboctahedra that share corners with seventeen CoCe6Co6 cuboctahedra, edges with eight CoCe5Co7 cuboctahedra, and faces with fourteen CoCe6Co6 cuboctahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-09-03. Materials Data on Ce2Co7 by Materials Project. https://doi.org/10.17188/1758673

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↗