Search NASA⌕ Search

DOE OSTI · 1271592

Materials Data on Ba12Cl5F19 by Materials Project

Abstract

Ba12F19Cl5 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to four equivalent Cl1- and five F1- atoms. All Ba–Cl bond lengths are 3.40 Å. There are a spread of Ba–F bond distances ranging from 2.54–2.73 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to two equivalent Cl1- and seven F1- atoms. Both Ba–Cl bond lengths are 3.37 Å. There are a spread of Ba–F bond distances ranging from 2.62–3.07 Å. In the third Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to two equivalent Cl1- and seven F1- atoms. Both Ba–Cl bond lengths are 3.43 Å. There are a spread of Ba–F bond distances ranging from 2.67–2.77 Å. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 12-coordinate geometry to six Ba2+ and eight F1- atoms. There are a spread of Cl–F bond distances ranging from 3.45–3.53 Å. In the second Cl1- site, Cl1- is bonded in a 6-coordinate geometry to six equivalent Ba2+ atoms. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Ba2+ and six equivalent Cl1- atoms. In the second F1- site, F1- is bonded to four Ba2+ and two equivalent Cl1- atoms to form a mixture of edge, face, and corner-sharing FBa4Cl2 tetrahedra. In the third F1- site, F1- is bonded to four Ba2+ atoms to form a mixture of edge and corner-sharing FBa4 tetrahedra. In the fourth F1- site, F1- is bonded in a 5-coordinate geometry to five Ba2+ atoms. In the fifth F1- site, F1- is bonded to four Ba2+ and two equivalent Cl1- atoms to form a mixture of face and corner-sharing FBa4Cl2 tetrahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-02. Materials Data on Ba12Cl5F19 by Materials Project. https://doi.org/10.17188/1271592

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↗