Search NASA⌕ Search

DOE OSTI · 1289059

Materials Data on Ce3Th2O9 by Materials Project

Abstract

Th2Ce3O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Th4+ sites. In the first Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.37–2.53 Å. In the second Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.36–2.55 Å. There are three inequivalent Ce+3.33+ sites. In the first Ce+3.33+ site, Ce+3.33+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ce–O bond distances ranging from 2.33–2.51 Å. In the second Ce+3.33+ site, Ce+3.33+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.31–2.37 Å. In the third Ce+3.33+ site, Ce+3.33+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ce–O bond distances ranging from 2.33–2.50 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of distorted edge and corner-sharing OCe3Th tetrahedra. In the second O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the third O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCe3Th tetrahedra and edges with six OCeTh3 tetrahedra. In the fourth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCe3Th tetrahedra and edges with four OCeTh3 tetrahedra. In the fifth O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the sixth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the seventh O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCe3Th tetrahedra and edges with six OCeTh3 tetrahedra. In the eighth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the ninth O2- site, O2- is bonded to four Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-07-18. Materials Data on Ce3Th2O9 by Materials Project. https://doi.org/10.17188/1289059

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↗