Search NASA⌕ Search

DOE OSTI · 1272036

Materials Data on Ag2Te4O11 by Materials Project

Abstract

Ag2Te4O11 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ag–O bond distances ranging from 2.47–3.17 Å. In the second Ag1+ site, Ag1+ is bonded to eight O2- atoms to form distorted AgO8 hexagonal bipyramids that share a cornercorner with one TeO6 octahedra, a cornercorner with one TeO5 square pyramid, edges with two equivalent AgO8 hexagonal bipyramids, edges with two TeO6 octahedra, and edges with five TeO5 square pyramids. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ag–O bond distances ranging from 2.56–2.81 Å. There are four inequivalent Te5+ sites. In the first Te5+ site, Te5+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with three equivalent TeO6 octahedra, corners with three TeO5 square pyramids, and an edgeedge with one AgO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 39–43°. There are a spread of Te–O bond distances ranging from 1.92–2.00 Å. In the second Te5+ site, Te5+ is bonded to five O2- atoms to form distorted TeO5 square pyramids that share a cornercorner with one AgO8 hexagonal bipyramid, corners with two TeO6 octahedra, a cornercorner with one TeO5 square pyramid, edges with three equivalent AgO8 hexagonal bipyramids, and an edgeedge with one TeO5 square pyramid. The corner-sharing octahedra tilt angles range from 41–60°. There are a spread of Te–O bond distances ranging from 1.92–2.31 Å. In the third Te5+ site, Te5+ is bonded to six O2- atoms to form TeO6 octahedra that share a cornercorner with one AgO8 hexagonal bipyramid, corners with three equivalent TeO6 octahedra, corners with three TeO5 square pyramids, and an edgeedge with one AgO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 39–43°. There are a spread of Te–O bond distances ranging from 1.93–2.02 Å. In the fourth Te5+ site, Te5+ is bonded to five O2- atoms to form TeO5 square pyramids that share corners with four TeO6 octahedra, a cornercorner with one TeO5 square pyramid, and edges with two equivalent AgO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 42–52°. There are a spread of Te–O bond distances ranging from 1.92–2.14 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ag1+ and two Te5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ag1+ and two Te5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ag1+ and two Te5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Ag1+ and two Te5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ag1+ and two Te5+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ag1+ and two equivalent Te5+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Ag1+ and two Te5+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ag1+ and two Te5+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Ag1+ and two Te5+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te5+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Ag1+ and two Te5+ atoms.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-07-20. Materials Data on Ag2Te4O11 by Materials Project. https://doi.org/10.17188/1272036

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↗