Search NASA⌕ Search

DOE OSTI · 1685101

Materials Data on KNaAl6Si6(HO6)4 by Materials Project

Abstract

KNaAl6Si6(HO6)4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with two AlO4 tetrahedra and corners with ten SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.68–2.87 Å. In the second K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with four AlO4 tetrahedra and corners with eight SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.76–2.88 Å. In the third K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with four AlO4 tetrahedra and corners with eight SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.74–2.91 Å. In the fourth K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with four AlO4 tetrahedra and corners with eight SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.76–2.88 Å. There are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two AlO4 tetrahedra and corners with ten SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.46–2.99 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.57–3.09 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two AlO4 tetrahedra and corners with ten SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.46–3.04 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two AlO4 tetrahedra and corners with ten SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.46–2.99 Å. There are twenty-four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–71°. There is three shorter (1.75 Å) and one longer (1.77 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–71°. There is one shorter (1.75 Å) and three longer (1.76 Å) Al–O bond length. In the fifth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–72°. There is two shorter (1.75 Å) and two longer (1.76 Å) Al–O bond length. In the seventh Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–1.98 Å. In the eighth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–71°. There is two shorter (1.75 Å) and two longer (1.76 Å) Al–O bond length. In the ninth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the tenth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the eleventh Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the twelfth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the thirteenth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the fourteenth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one KO6 octahedra, a cornercorner with one NaO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–69°. There is one shorter (1.75 Å) and three longer (1.76 Å) Al–O bond length. In the fifteenth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–1.99 Å. In the sixteenth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one KO6 octahedra, a cornercorner with one NaO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–70°. There are a spread of Al–O bond distances ranging from 1.74–1.77 Å. In the seventeenth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the eighteenth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–71°. There is two shorter (1.75 Å) and two longer (1.76 Å) Al–O bond length. In the nineteenth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–2.00 Å. In the twentieth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–72°. There is two shorter (1.75 Å) and two longer (1.76 Å) Al–O bond length. In the twenty-first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.98 Å. In the twenty-second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. In the twenty-third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.98 Å. In the twenty-fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–1.99 Å. There are twenty-four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two KO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–72°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two KO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–72°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–72°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–72°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with two AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–65°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two KO6 octahedra, corners with two AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–72°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one KO6 octahedra, a cornercorner with one NaO6 octahedra, corners with two AlO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with tw

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-29. Materials Data on KNaAl6Si6(HO6)4 by Materials Project. https://doi.org/10.17188/1685101

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↗