Search NASA⌕ Search

DOE OSTI · 1717783

Materials Data on K3Sb7(SeO4)3 by Materials Project

Abstract

K3Sb7(SeO4)3 crystallizes in the monoclinic P2_1 space group. The structure is one-dimensional and consists of one K3Sb7(SeO4)3 ribbon oriented in the (0, 1, 0) direction. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to one Se2- and nine O2- atoms. The K–Se bond length is 3.60 Å. There are a spread of K–O bond distances ranging from 2.71–3.12 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.90–3.18 Å. In the third K1+ site, K1+ is bonded in a 6-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.68–3.16 Å. There are seven inequivalent Sb+3.86+ sites. In the first Sb+3.86+ site, Sb+3.86+ is bonded in a 3-coordinate geometry to three O2- atoms. There are one shorter (2.00 Å) and two longer (2.02 Å) Sb–O bond lengths. In the second Sb+3.86+ site, Sb+3.86+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.01 Å) and one longer (2.03 Å) Sb–O bond lengths. In the third Sb+3.86+ site, Sb+3.86+ is bonded in a 3-coordinate geometry to three O2- atoms. There are one shorter (2.01 Å) and two longer (2.02 Å) Sb–O bond lengths. In the fourth Sb+3.86+ site, Sb+3.86+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.99–2.01 Å. In the fifth Sb+3.86+ site, Sb+3.86+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is two shorter (1.99 Å) and one longer (2.00 Å) Sb–O bond length. In the sixth Sb+3.86+ site, Sb+3.86+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.99–2.01 Å. In the seventh Sb+3.86+ site, Sb+3.86+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are two shorter (2.56 Å) and one longer (2.57 Å) Sb–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted single-bond geometry to one K1+ and one Sb+3.86+ atom. In the second Se2- site, Se2- is bonded in a distorted single-bond geometry to one Sb+3.86+ atom. In the third Se2- site, Se2- is bonded in a distorted single-bond geometry to one Sb+3.86+ atom. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Sb+3.86+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Sb+3.86+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+ and two Sb+3.86+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and two O2- atoms. There is one shorter (1.34 Å) and one longer (1.35 Å) O–O bond length. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to three K1+ and one O2- atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+ and one O2- atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Sb+3.86+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Sb+3.86+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Sb+3.86+ atoms. In the tenth O2- site, O2- is bonded to two K1+ and two Sb+3.86+ atoms to form distorted corner-sharing OK2Sb2 tetrahedra. In the eleventh O2- site, O2- is bonded to two K1+ and two Sb+3.86+ atoms to form distorted corner-sharing OK2Sb2 tetrahedra. In the twelfth O2- site, O2- is bonded to two K1+ and two Sb+3.86+ atoms to form distorted corner-sharing OK2Sb2 tetrahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-30. Materials Data on K3Sb7(SeO4)3 by Materials Project. https://doi.org/10.17188/1717783

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↗