Search NASA⌕ Search

DOE OSTI · 1673030

Materials Data on SrU3(SeO9)2 by Materials Project

Abstract

SrU3(SeO7)2(O2)2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional and consists of four hydrogen peroxide molecules and one SrU3(SeO7)2 framework. In the SrU3(SeO7)2 framework, Sr is bonded to six O atoms to form distorted SrO6 pentagonal pyramids that share corners with four equivalent UO7 pentagonal bipyramids. There are a spread of Sr–O bond distances ranging from 2.61–2.76 Å. There are two inequivalent U sites. In the first U site, U is bonded to seven O atoms to form distorted UO7 pentagonal bipyramids that share corners with two equivalent SrO6 pentagonal pyramids and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of U–O bond distances ranging from 1.86–2.39 Å. In the second U site, U is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of U–O bond distances ranging from 1.84–2.64 Å. Se is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Se–O bond distances ranging from 1.71–1.74 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to three U atoms. In the second O site, O is bonded in a trigonal planar geometry to three U atoms. In the third O site, O is bonded in a distorted single-bond geometry to one Sr and one U atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one Sr and one U atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and one U atom. In the sixth O site, O is bonded in a 3-coordinate geometry to two U and one Se atom. In the seventh O site, O is bonded in a 3-coordinate geometry to two U and one Se atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to one U and one Se atom.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-05-02. Materials Data on SrU3(SeO9)2 by Materials Project. https://doi.org/10.17188/1673030

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↗