Search NASA⌕ Search

DOE OSTI · 1197571

Materials Data on Er2S3 by Materials Project

Abstract

Er2S3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are six inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share corners with five ErS6 octahedra, edges with four ErS6 octahedra, edges with four equivalent ErS7 pentagonal bipyramids, and a faceface with one ErS6 octahedra. The corner-sharing octahedra tilt angles range from 32–49°. There are a spread of Er–S bond distances ranging from 2.67–2.91 Å. In the second Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share corners with three ErS6 octahedra, corners with two equivalent ErS7 pentagonal bipyramids, edges with two equivalent ErS6 octahedra, edges with six ErS7 pentagonal bipyramids, and a faceface with one ErS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 49–51°. There are a spread of Er–S bond distances ranging from 2.70–2.94 Å. In the third Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share corners with two ErS6 octahedra, corners with two equivalent ErS7 pentagonal bipyramids, edges with two equivalent ErS6 octahedra, edges with six ErS7 pentagonal bipyramids, and a faceface with one ErS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–34°. There are a spread of Er–S bond distances ranging from 2.71–2.93 Å. In the fourth Er3+ site, Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with four ErS6 octahedra, corners with five ErS7 pentagonal bipyramids, edges with four equivalent ErS6 octahedra, and a faceface with one ErS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 63–67°. There are a spread of Er–S bond distances ranging from 2.67–2.82 Å. In the fifth Er3+ site, Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with four ErS6 octahedra, corners with three ErS7 pentagonal bipyramids, edges with three ErS6 octahedra, and edges with four ErS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 14–67°. There are a spread of Er–S bond distances ranging from 2.62–2.81 Å. In the sixth Er3+ site, Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with four ErS6 octahedra, corners with two ErS7 pentagonal bipyramids, edges with three ErS6 octahedra, and edges with four ErS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 14–63°. There are a spread of Er–S bond distances ranging from 2.67–2.84 Å. There are nine inequivalent S2- sites. In the first S2- site, S2- is bonded to five Er3+ atoms to form distorted SEr5 trigonal bipyramids that share corners with seven SEr4 trigonal pyramids, edges with four equivalent SEr5 trigonal bipyramids, and edges with six SEr4 trigonal pyramids. In the second S2- site, S2- is bonded to five Er3+ atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent SEr4 tetrahedra, corners with five SEr4 trigonal pyramids, edges with two equivalent SEr5 square pyramids, an edgeedge with one SEr4 tetrahedra, edges with two equivalent SEr5 trigonal bipyramids, and edges with three equivalent SEr4 trigonal pyramids. In the third S2- site, S2- is bonded to five Er3+ atoms to form SEr5 square pyramids that share a cornercorner with one SEr4 tetrahedra, corners with seven SEr4 trigonal pyramids, edges with two equivalent SEr5 square pyramids, edges with two equivalent SEr4 tetrahedra, edges with two equivalent SEr5 trigonal bipyramids, and an edgeedge with one SEr4 trigonal pyramid. In the fourth S2- site, S2- is bonded to four Er3+ atoms to form SEr4 trigonal pyramids that share a cornercorner with one SEr5 square pyramid, corners with three equivalent SEr4 tetrahedra, corners with two equivalent SEr5 trigonal bipyramids, corners with two equivalent SEr4 trigonal pyramids, edges with three equivalent SEr5 trigonal bipyramids, and edges with two equivalent SEr4 trigonal pyramids. In the fifth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to four Er3+ atoms. In the sixth S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with two equivalent SEr5 square pyramids, a cornercorner with one SEr4 tetrahedra, corners with two equivalent SEr5 trigonal bipyramids, corners with eight SEr4 trigonal pyramids, and edges with three equivalent SEr5 trigonal bipyramids. In the seventh S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with two equivalent SEr5 square pyramids, corners with five SEr5 trigonal bipyramids, corners with six SEr4 trigonal pyramids, an edgeedge with one SEr5 trigonal bipyramid, and edges with four SEr4 trigonal pyramids. In the eighth S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 tetrahedra that share a cornercorner with one SEr5 square pyramid, corners with two equivalent SEr4 tetrahedra, corners with four equivalent SEr5 trigonal bipyramids, corners with four SEr4 trigonal pyramids, edges with two equivalent SEr5 square pyramids, edges with two equivalent SEr4 tetrahedra, and an edgeedge with one SEr5 trigonal bipyramid. In the ninth S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with two equivalent SEr5 square pyramids, corners with three SEr5 trigonal bipyramids, corners with six SEr4 trigonal pyramids, an edgeedge with one SEr5 square pyramid, edges with two equivalent SEr5 trigonal bipyramids, and edges with two equivalent SEr4 trigonal pyramids.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-07-22. Materials Data on Er2S3 by Materials Project. https://doi.org/10.17188/1197571

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↗