Search NASA⌕ Search

DOE OSTI · 1687570

Materials Data on La4Ti5(S6O)2 by Materials Project

Abstract

La4Ti5(S6O)2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 1-coordinate geometry to eight S2- and one O2- atom. There are a spread of La–S bond distances ranging from 2.93–3.17 Å. The La–O bond length is 2.48 Å. In the second La3+ site, La3+ is bonded in a 1-coordinate geometry to eight S2- and one O2- atom. There are a spread of La–S bond distances ranging from 2.91–3.20 Å. The La–O bond length is 2.50 Å. In the third La3+ site, La3+ is bonded in a 1-coordinate geometry to eight S2- and one O2- atom. There are a spread of La–S bond distances ranging from 2.90–3.14 Å. The La–O bond length is 2.47 Å. In the fourth La3+ site, La3+ is bonded in a 1-coordinate geometry to eight S2- and one O2- atom. There are a spread of La–S bond distances ranging from 2.91–3.20 Å. The La–O bond length is 2.50 Å. There are ten inequivalent Ti+3.20+ sites. In the first Ti+3.20+ site, Ti+3.20+ is bonded to four S2- and two O2- atoms to form distorted TiS4O2 octahedra that share corners with two equivalent TiS6 octahedra, an edgeedge with one TiS6 octahedra, and a faceface with one TiS4O2 octahedra. The corner-sharing octahedral tilt angles are 52°. There are two shorter (2.39 Å) and two longer (2.59 Å) Ti–S bond lengths. Both Ti–O bond lengths are 1.98 Å. In the second Ti+3.20+ site, Ti+3.20+ is bonded in a 6-coordinate geometry to four S2- and two O2- atoms. There are two shorter (2.34 Å) and two longer (2.68 Å) Ti–S bond lengths. Both Ti–O bond lengths are 1.97 Å. In the third Ti+3.20+ site, Ti+3.20+ is bonded to four S2- and two O2- atoms to form distorted TiS4O2 octahedra that share corners with four TiS6 octahedra, an edgeedge with one TiS6 octahedra, and a faceface with one TiS4O2 octahedra. The corner-sharing octahedra tilt angles range from 36–52°. There are two shorter (2.37 Å) and two longer (2.60 Å) Ti–S bond lengths. There is one shorter (1.97 Å) and one longer (1.99 Å) Ti–O bond length. In the fourth Ti+3.20+ site, Ti+3.20+ is bonded in a 6-coordinate geometry to four S2- and two O2- atoms. There are two shorter (2.34 Å) and two longer (2.67 Å) Ti–S bond lengths. Both Ti–O bond lengths are 1.97 Å. In the fifth Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form edge-sharing TiS6 octahedra. There are a spread of Ti–S bond distances ranging from 2.44–2.50 Å. In the sixth Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with two equivalent TiS6 octahedra and an edgeedge with one TiS4O2 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of Ti–S bond distances ranging from 2.43–2.48 Å. In the seventh Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form corner-sharing TiS6 octahedra. The corner-sharing octahedra tilt angles range from 30–32°. There are a spread of Ti–S bond distances ranging from 2.32–2.87 Å. In the eighth Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with four TiS4O2 octahedra and an edgeedge with one TiS6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–S bond distances ranging from 2.26–2.68 Å. In the ninth Ti+3.20+ site, Ti+3.20+ is bonded in a 5-coordinate geometry to five S2- atoms. There are a spread of Ti–S bond distances ranging from 2.45–2.85 Å. In the tenth Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with six TiS4O2 octahedra and an edgeedge with one TiS6 octahedra. The corner-sharing octahedra tilt angles range from 30–45°. There are a spread of Ti–S bond distances ranging from 2.41–2.87 Å. There are eighteen inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to two La3+ and three Ti+3.20+ atoms. In the second S2- site, S2- is bonded in a 4-coordinate geometry to two La3+ and two Ti+3.20+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to two La3+ and three Ti+3.20+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to two La3+ and two Ti+3.20+ atoms. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to five Ti+3.20+ atoms. In the sixth S2- site, S2- is bonded in a 1-coordinate geometry to four La3+ and one Ti+3.20+ atom. In the seventh S2- site, S2- is bonded in a 5-coordinate geometry to four La3+ and one Ti+3.20+ atom. In the eighth S2- site, S2- is bonded in a 5-coordinate geometry to four La3+ and one Ti+3.20+ atom. In the ninth S2- site, S2- is bonded in a 1-coordinate geometry to four La3+ and one Ti+3.20+ atom. In the tenth S2- site, S2- is bonded in a 6-coordinate geometry to four La3+ and two Ti+3.20+ atoms. In the eleventh S2- site, S2- is bonded in a 6-coordinate geometry to four La3+ and two Ti+3.20+ atoms. In the twelfth S2- site, S2- is bonded to four La3+ and two Ti+3.20+ atoms to form distorted SLa4Ti2 pentagonal pyramids that share corners with four OLa2Ti2 tetrahedra, a cornercorner with one SLa2Ti2 trigonal pyramid, faces with two equivalent SLa4Ti square pyramids, and a faceface with one SLa2Ti2 trigonal pyramid. In the thirteenth S2- site, S2- is bonded in a 6-coordinate geometry to four La3+ and two Ti+3.20+ atoms. In the fourteenth S2- site, S2- is bonded to four La3+ and one Ti+3.20+ atom to form distorted SLa4Ti square pyramids that share a cornercorner with one SLa4Ti square pyramid, corners with four OLa2Ti2 tetrahedra, corners with two SLa2Ti2 trigonal pyramids, and a faceface with one SLa4Ti2 pentagonal pyramid. In the fifteenth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent La3+ and two Ti+3.20+ atoms. In the sixteenth S2- site, S2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form SLa2Ti2 trigonal pyramids that share a cornercorner with one SLa4Ti2 pentagonal pyramid, corners with two equivalent SLa4Ti square pyramids, corners with two equivalent OLa2Ti2 tetrahedra, and an edgeedge with one SLa2Ti2 trigonal pyramid. In the seventeenth S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent La3+ and one Ti+3.20+ atom. In the eighteenth S2- site, S2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form distorted SLa2Ti2 trigonal pyramids that share corners with two equivalent SLa4Ti square pyramids, corners with two equivalent OLa2Ti2 tetrahedra, an edgeedge with one SLa2Ti2 trigonal pyramid, and a faceface with one SLa4Ti2 pentagonal pyramid. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form distorted OLa2Ti2 tetrahedra that share corners with two equivalent SLa4Ti square pyramids and corners with two OLa2Ti2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form distorted OLa2Ti2 tetrahedra that share corners with two equivalent SLa4Ti2 pentagonal pyramids, corners with two equivalent SLa4Ti square pyramids, corners with two OLa2Ti2 tetrahedra, and corners with two equivalent SLa2Ti2 trigonal pyramids. In the third O2- site, O2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form distorted OLa2Ti2 tetrahedra that share corners with two equivalent SLa4Ti square pyramids, corners with two OLa2Ti2 tetrahedra, and corners with two equivalent SLa2Ti2 trigonal pyramids. In the fourth O2- site, O2- is bonded to two equivalent La3+ and two Ti+3.20+ atoms to form distorted OLa2Ti2 tetrahedra that share corners with two equivalent SLa4Ti2 pentagonal pyramids, corners with two equivalent SLa4Ti square pyramids, and corners with two OLa2Ti2 tetrahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-30. Materials Data on La4Ti5(S6O)2 by Materials Project. https://doi.org/10.17188/1687570

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↗