Search NASA⌕ Search

DOE OSTI · 1205282

Materials Data on Cd2(TeO3)3 by Materials Project

Abstract

Cd2Te3O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Cd–O bond distances ranging from 2.32–2.54 Å. In the second Cd2+ site, Cd2+ is bonded to seven O2- atoms to form distorted CdO7 pentagonal bipyramids that share corners with two equivalent TeO6 octahedra and an edgeedge with one CdO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 52–54°. There are a spread of Cd–O bond distances ranging from 2.32–2.59 Å. There are three inequivalent Te+4.67+ sites. In the first Te+4.67+ site, Te+4.67+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra and corners with two equivalent CdO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of Te–O bond distances ranging from 1.89–2.03 Å. In the second Te+4.67+ site, Te+4.67+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.63 Å. In the third Te+4.67+ site, Te+4.67+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.91–1.94 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Cd2+ and two Te+4.67+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cd2+ and one Te+4.67+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Te+4.67+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te+4.67+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te+4.67+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Cd2+ and two Te+4.67+ atoms. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cd2+ and one Te+4.67+ atom. In the eighth O2- site, O2- is bonded to three Cd2+ and one Te+4.67+ atom to form a mixture of distorted edge and corner-sharing OCd3Te tetrahedra. In the ninth O2- site, O2- is bonded to three Cd2+ and one Te+4.67+ atom to form a mixture of distorted edge and corner-sharing OCd3Te tetrahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-30. Materials Data on Cd2(TeO3)3 by Materials Project. https://doi.org/10.17188/1205282

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↗