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DOE OSTI2020

Materials Data on RbNaB4H4O13 by Materials Project

RbNaB4H4O13 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Rb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Rb–O bond distances ranging from 2.90–3.24 Å. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.28–2.56 Å. There are four inequivalent B sites. In the first B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.37–1.39 Å. In the second B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.37–1.39 Å. In the third B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.51 Å. In the fourth B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.44–1.51 Å. There are four inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. In the second H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. In the third H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.97 Å. In the fourth H site, H is bonded in a linear geometry to two O atoms. There is one shorter (1.01 Å) and one longer (1.61 Å) H–O bond length. There are thirteen inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to two B and one H atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to two B atoms. In the third O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to two B atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the sixth O site, O is bonded in a distorted water-like geometry to one Rb, one B, and one H atom. In the seventh O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent Rb, one B, and one H atom. In the eighth O site, O is bonded in a water-like geometry to one Rb, one B, and one H atom. In the ninth O site, O is bonded in a 2-coordinate geometry to one Rb, one Na, one B, and one H atom. In the tenth O site, O is bonded in a distorted single-bond geometry to one Rb and one Na atom. In the eleventh O site, O is bonded in a single-bond geometry to one Na atom. In the twelfth O site, O is bonded in a single-bond geometry to one Na atom. In the thirteenth O site, O is bonded in an L-shaped geometry to two equivalent Na atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaMg30SiO32 by Materials Project

NaMg30SiO32 is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Na is bonded to six O atoms to form NaO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.25 Å) and four longer (2.28 Å) Na–O bond lengths. There are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent SiO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.00–2.40 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SiO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.10 Å) and two longer (2.36 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.11–2.18 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.03 Å) and four longer (2.17 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one NaO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. There are a spread of Mg–O bond distances ranging from 2.11–2.19 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–3°. There are two shorter (2.13 Å) and four longer (2.15 Å) Mg–O bond lengths. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–15°. There are a spread of Mg–O bond distances ranging from 2.12–2.17 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one NaO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Mg–O bond distances ranging from 2.12–2.16 Å. Si is bonded to six O atoms to form SiO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is four shorter (1.87 Å) and two longer (1.91 Å) Si–O bond length. There are seventeen inequivalent O sites. In the first O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. In the second O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. In the third O site, O is bonded to one Na and five Mg atoms to form a mixture of corner and edge-sharing ONaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 2–3°. In the fifth O site, O is bonded to five Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–12°. In the sixth O site, O is bonded to one Na and five Mg atoms to form ONaMg5 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. The O–Mg bond length is 2.00 Å. In the seventh O site, O is bonded to one Na and five Mg atoms to form ONaMg5 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of O–Mg bond distances ranging from 2.00–2.14 Å. In the eighth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are two shorter (2.13 Å) and two longer (2.15 Å) O–Mg bond lengths. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six ONaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. The O–Mg bond length is 2.11 Å. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six ONaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are two shorter (2.13 Å) and two longer (2.14 Å) O–Mg bond lengths. In the twelfth O site, O is bonded to five Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are two shorter (2.17 Å) and one longer (2.40 Å) O–Mg bond lengths. In the thirteenth O site, O is bonded to one Na and five Mg atoms to form ONaMg5 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. Both O–Mg bond lengths are 2.14 Å. In the fourteenth O site, O is bonded to one Na and five Mg atoms to form ONaMg5 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are two shorter (2.11 Å) and two longer (2.14 Å) O–Mg bond lengths. In the fifteenth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are two shorter (2.13 Å) and one longer (2.18 Å) O–Mg bond lengths. In the sixteenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six ONaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. Both O–Mg bond lengths are 2.14 Å. In the seventeenth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of O–Mg bond distances ranging from 2.13–2.18 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na3Al3Ge3O16 by Materials Project

Na3Al3Ge3O16 crystallizes in the trigonal R3c space group. The structure is three-dimensional. Na is bonded in a 3-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.30–2.81 Å. Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four equivalent GeO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.78 Å. Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with four equivalent AlO4 tetrahedra. There is one shorter (1.74 Å) and three longer (1.77 Å) Ge–O bond length. There are six inequivalent O sites. In the first O site, O is bonded in a distorted hexagonal planar geometry to three equivalent Na and three equivalent O atoms. All O–O bond lengths are 1.70 Å. In the second O site, O is bonded in a 3-coordinate geometry to two equivalent Na and one O atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one Al and one Ge atom. In the fourth O site, O is bonded in a trigonal planar geometry to one Na, one Al, and one Ge atom. In the fifth O site, O is bonded in a trigonal planar geometry to one Na, one Al, and one Ge atom. In the sixth O site, O is bonded in a trigonal planar geometry to one Na, one Al, and one Ge atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsNaMg6 by Materials Project

CsNaMg6 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Cs is bonded to two equivalent Na and ten Mg atoms to form CsNa2Mg10 cuboctahedra that share corners with four equivalent NaCs2Mg10 cuboctahedra, corners with six equivalent CsNa2Mg10 cuboctahedra, edges with two equivalent NaCs2Mg10 cuboctahedra, faces with two equivalent CsNa2Mg10 cuboctahedra, and faces with two equivalent NaCs2Mg10 cuboctahedra. Both Cs–Na bond lengths are 3.40 Å. There are a spread of Cs–Mg bond distances ranging from 3.49–3.60 Å. Na is bonded to two equivalent Cs and ten Mg atoms to form NaCs2Mg10 cuboctahedra that share corners with four equivalent CsNa2Mg10 cuboctahedra, corners with six equivalent NaCs2Mg10 cuboctahedra, edges with two equivalent CsNa2Mg10 cuboctahedra, faces with two equivalent CsNa2Mg10 cuboctahedra, and faces with two equivalent NaCs2Mg10 cuboctahedra. There are a spread of Na–Mg bond distances ranging from 3.47–3.55 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Cs, two equivalent Na, and eight Mg atoms. There are a spread of Mg–Mg bond distances ranging from 3.36–3.52 Å. In the second Mg site, Mg is bonded in a 11-coordinate geometry to two equivalent Cs, two equivalent Na, and three Mg atoms. The Mg–Mg bond length is 3.29 Å. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Na and six Mg atoms. Both Mg–Mg bond lengths are 3.40 Å. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Cs and eight Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsNa5(FeO3)2 by Materials Project

CsNa5(FeO3)2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. Cs1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Cs–O bond distances ranging from 3.01–3.14 Å. There are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.68 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.67 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.75 Å. In the fourth Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share corners with two FeO4 tetrahedra, an edgeedge with one NaO4 tetrahedra, and edges with two FeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.34–2.61 Å. In the fifth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.96 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with four FeO4 tetrahedra and edges with two equivalent NaO5 trigonal bipyramids. There are two shorter (2.35 Å) and two longer (2.38 Å) Na–O bond lengths. In the seventh 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 2.42–2.77 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share a cornercorner with one NaO4 tetrahedra, corners with two FeO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 1.86–1.96 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share a cornercorner with one NaO4 tetrahedra, corners with two FeO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 1.87–1.95 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to four Na1+ and two equivalent Fe3+ atoms to form ONa4Fe2 octahedra that share corners with three equivalent ONa4Fe2 octahedra and edges with two equivalent OCsNa3Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–32°. In the second O2- site, O2- is bonded to four Na1+ and two equivalent Fe3+ atoms to form ONa4Fe2 octahedra that share corners with three equivalent ONa4Fe2 octahedra and edges with two equivalent OCsNa3Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–32°. In the third O2- site, O2- is bonded to one Cs1+, three Na1+, and two Fe3+ atoms to form distorted edge-sharing OCsNa3Fe2 octahedra. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Cs1+, four Na1+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to one Cs1+, four Na1+, and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to one Cs1+, four Na1+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Fe3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaCdP2NO10 by Materials Project

NaCdP2NO10 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.33–2.94 Å. Cd is bonded to six O atoms to form distorted CdO6 octahedra that share corners with five PO4 tetrahedra. There are a spread of Cd–O bond distances ranging from 2.19–2.46 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three equivalent CdO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–58°. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent CdO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–58°. There are a spread of P–O bond distances ranging from 1.51–1.65 Å. N is bonded in a single-bond geometry to one O atom. The N–O bond length is 1.20 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two equivalent Na and one P atom. In the second O site, O is bonded in a distorted single-bond geometry to one N and one O atom. The O–O bond length is 1.40 Å. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one Na and one O atom. In the fourth O site, O is bonded in a water-like geometry to one Na and one Cd atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Na and two P atoms. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to one Cd and one P atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Cd and one P atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Cd and one P atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Cd, and one P atom. In the tenth O site, O is bonded in a distorted bent 120 degrees geometry to one Cd and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na3Zn4P3O19 by Materials Project

Na3Zn4P3O19 crystallizes in the trigonal R3c space group. The structure is three-dimensional. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.34–2.96 Å. There are two inequivalent Zn sites. In the first Zn site, Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with three ZnO4 tetrahedra and corners with three equivalent PO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.95–1.97 Å. In the second Zn site, Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with three equivalent ZnO4 tetrahedra and corners with three equivalent PO4 tetrahedra. There is one shorter (1.97 Å) and three longer (1.99 Å) Zn–O bond length. P is bonded to four O atoms to form PO4 tetrahedra that share corners with four ZnO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Zn and one P atom. In the second O site, O is bonded in a trigonal planar geometry to one Na, one Zn, and one P atom. In the third O site, O is bonded in a bent 120 degrees geometry to one Na and one O atom. The O–O bond length is 1.24 Å. In the fourth O site, O is bonded in a 2-coordinate geometry to one Na, one Zn, and one P atom. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to two equivalent Na and one O atom. In the sixth O site, O is bonded in a tetrahedral geometry to four Zn atoms. In the seventh O site, O is bonded in a trigonal planar geometry to one Na, one Zn, and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na3TaS4 by Materials Project

Na3TaS4 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. there are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six S2- atoms to form distorted NaS6 octahedra that share corners with two equivalent TaS4 tetrahedra, edges with six NaS6 octahedra, and edges with two equivalent TaS4 tetrahedra. There are a spread of Na–S bond distances ranging from 2.89–3.28 Å. In the second Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with two equivalent TaS4 tetrahedra, edges with six NaS6 octahedra, and edges with two equivalent TaS4 tetrahedra. There are a spread of Na–S bond distances ranging from 2.91–3.30 Å. In the third Na1+ site, Na1+ is bonded to six S2- atoms to form distorted NaS6 octahedra that share corners with two equivalent NaS6 octahedra, corners with four TaS4 tetrahedra, edges with four NaS6 octahedra, an edgeedge with one TaS4 tetrahedra, and a faceface with one NaS6 octahedra. The corner-sharing octahedra tilt angles range from 30–59°. There are a spread of Na–S bond distances ranging from 2.83–3.23 Å. In the fourth Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with six NaS6 octahedra, corners with four TaS4 tetrahedra, edges with two NaS6 octahedra, an edgeedge with one TaS4 tetrahedra, and a faceface with one NaS6 octahedra. The corner-sharing octahedra tilt angles range from 30–59°. There are a spread of Na–S bond distances ranging from 2.85–3.01 Å. In the fifth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Na–S bond distances ranging from 2.93–3.44 Å. In the sixth Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with four equivalent NaS6 octahedra, corners with four TaS4 tetrahedra, edges with four NaS6 octahedra, and an edgeedge with one TaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–39°. There are a spread of Na–S bond distances ranging from 2.87–3.02 Å. In the seventh Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Na–S bond distances ranging from 2.96–3.50 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to four S2- atoms to form TaS4 tetrahedra that share corners with seven NaS6 octahedra and edges with three NaS6 octahedra. The corner-sharing octahedra tilt angles range from 9–77°. There are one shorter (2.28 Å) and three longer (2.29 Å) Ta–S bond lengths. In the second Ta5+ site, Ta5+ is bonded to four S2- atoms to form TaS4 tetrahedra that share corners with seven NaS6 octahedra and edges with two NaS6 octahedra. The corner-sharing octahedra tilt angles range from 10–75°. There are a spread of Ta–S bond distances ranging from 2.28–2.30 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to five Na1+ and one Ta5+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to five Na1+ and one Ta5+ atom. In the third S2- site, S2- is bonded in a 5-coordinate geometry to four Na1+ and one Ta5+ atom. In the fourth S2- site, S2- is bonded to four Na1+ and one Ta5+ atom to form a mixture of distorted corner and edge-sharing SNa4Ta square pyramids. In the fifth S2- site, S2- is bonded to four Na1+ and one Ta5+ atom to form a mixture of distorted corner and edge-sharing SNa4Ta trigonal bipyramids. In the sixth S2- site, S2- is bonded in a 6-coordinate geometry to five Na1+ and one Ta5+ atom. In the seventh S2- site, S2- is bonded in a 6-coordinate geometry to five Na1+ and one Ta5+ atom. In the eighth S2- site, S2- is bonded to four Na1+ and one Ta5+ atom to form a mixture of distorted corner and edge-sharing SNa4Ta square pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na4Ga4Si19 by Materials Project

NaNa7(Ga4Si19)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional and consists of one sodium molecule and one Na7(Ga4Si19)2 framework. In the Na7(Ga4Si19)2 framework, there are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to seventeen Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.29–3.43 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.50–3.54 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.49–3.52 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.51–3.53 Å. In the fifth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.51–3.53 Å. In the sixth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.50–3.52 Å. In the seventh Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eighteen Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.30–3.42 Å. There are eight inequivalent Ga2+ sites. In the first Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share a cornercorner with one GaSi4 tetrahedra and corners with three SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.43–2.47 Å. In the second Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with two SiNa2Si4 tetrahedra. There are two shorter (2.44 Å) and two longer (2.47 Å) Ga–Si bond lengths. In the third Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with two SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.48 Å. In the fourth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with five SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.47 Å. In the fifth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with three SiNa2Si4 tetrahedra and corners with four GaSi4 tetrahedra. There are three shorter (2.45 Å) and one longer (2.46 Å) Ga–Si bond lengths. In the sixth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two SiNa3Si4 tetrahedra and corners with three GaSi4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.47 Å. In the seventh Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with three SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.46 Å. In the eighth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with five SiNa2Si4 tetrahedra. There are two shorter (2.45 Å) and two longer (2.46 Å) Ga–Si bond lengths. There are thirty-eight inequivalent Si+0.63- sites. In the first Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to one Ga2+ and three Si+0.63- atoms. There are two shorter (2.41 Å) and one longer (2.42 Å) Si–Si bond lengths. In the second Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to two Ga2+ and two Si+0.63- atoms. Both Si–Si bond lengths are 2.40 Å. In the third Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to two Ga2+ and two Si+0.63- atoms. There are one shorter (2.40 Å) and one longer (2.41 Å) Si–Si bond lengths. In the fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.35–2.39 Å. In the fifth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, two Ga2+, and two Si+0.63- atoms. There are one shorter (2.35 Å) and one longer (2.36 Å) Si–Si bond lengths. In the sixth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.36–2.41 Å. In the seventh Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.38–2.40 Å. In the eighth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are one shorter (2.39 Å) and two longer (2.40 Å) Si–Si bond lengths. In the ninth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.38 Å) and one longer (2.40 Å) Si–Si bond lengths. In the tenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.37 Å) and one longer (2.39 Å) Si–Si bond lengths. In the eleventh Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are two shorter (2.38 Å) and one longer (2.40 Å) Si–Si bond lengths. In the twelfth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.36 Å) and two longer (2.37 Å) Si–Si bond lengths. In the thirteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. All Si–Si bond lengths are 2.39 Å. In the fourteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.38–2.40 Å. In the fifteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, two Ga2+, and two Si+0.63- atoms. There are one shorter (2.33 Å) and one longer (2.36 Å) Si–Si bond lengths. In the sixteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.37–2.40 Å. In the seventeenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. Both Si–Si bond lengths are 2.38 Å. In the eighteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are two shorter (2.38 Å) and one longer (2.39 Å) Si–Si bond lengths. In the nineteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.38 Å) and one longer (2.39 Å) Si–Si bond lengths. In the twentieth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-first Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with two GaSi4 tetrahedra, corners with five SiNa2Si4 tetrahedra, and an edgeedge with one SiNa3Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the twenty-second Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. In the twenty-third Si+0.63- site, Si+0.63- is bonded to two Na1+ and four Si+0.63- atoms to form distorted SiNa2Si4 tetrahedra that share corners with four GaSi4 tetrahedra and corners with four SiNa3Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the twenty-fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, one Ga2+, and three Si+0.63- atoms. In the twenty-fifth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-sixth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.43 Å. In the twenty-seventh Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with five GaSi4 tetrahedra, corners with six SiNa2Si4 tetrahedra, and an edgeedge with one SiNa3Si4 tetrahedra. In the twenty-eighth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-ninth Si+0.63- site, Si+0.63- is bonded to two Na1+ and four Si+0.63- atoms to form distorted SiNa2Si4 tetrahedra that share corners with three SiNa2Si4 tetrahedra, corners with four GaSi4 tetrahedra, and edges with two SiNa3Si4 tetrahedra. The Si–Si bond length is 2.44 Å. In the thirtieth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, one Ga2+, and three Si+0.63- atoms. In the thirty-first Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, two Ga2+, and two Si+0.63- atoms. In the thirty-second Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with three GaSi4 tetrahedra, corners with five SiNa3Si4 tetrahedra, and an edgeedge with one SiNa2Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the thirty-third Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. In the thirty-fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the thirty-fifth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.42 Å. In the thirty-sixth Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with four GaSi4 tetrahedra, corners with five SiNa3Si4 tetrahedra, an edgeedge with one SiNa2Si4 tetrahedra, and a faceface with one SiNa3Si4 tetrahedra. In the thirty-seventh Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.42 Å. In the thirty-eighth Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with three GaSi4 tetrahedra, corners with six SiNa3Si4 tetrahedra, and a faceface with one SiNa3Si4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na2TiSi4H2O13 by Materials Project

Na2TiSi4H2O13 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.34–2.46 Å. Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Ti–O bond distances ranging from 1.94–2.00 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent TiO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–41°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one TiO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the second O site, O is bonded in a distorted trigonal planar geometry to one Na, one Ti, and one Si atom. In the third O site, O is bonded in a 3-coordinate geometry to one Na, one Ti, and one Si atom. In the fourth O site, O is bonded in a 3-coordinate geometry to one Na and two Si atoms. In the fifth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the sixth O site, O is bonded in a distorted single-bond geometry to two equivalent Na and one H atom. In the seventh O site, O is bonded in a 3-coordinate geometry to one Na, one Ti, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaCa2Al2As2O11F4 by Materials Project

NaCa2Al2As2O11F4 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na is bonded in a 4-coordinate geometry to three O and two equivalent F atoms. There are a spread of Na–O bond distances ranging from 2.46–2.72 Å. Both Na–F bond lengths are 2.19 Å. Ca is bonded in a 8-coordinate geometry to five O and three F atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.83 Å. There are a spread of Ca–F bond distances ranging from 2.38–2.41 Å. Al is bonded to four O and two F atoms to form AlO4F2 octahedra that share a cornercorner with one AlO4F2 octahedra and corners with two AsO4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are a spread of Al–O bond distances ranging from 1.87–1.96 Å. There is one shorter (1.80 Å) and one longer (1.92 Å) Al–F bond length. There are two inequivalent As sites. In the first As site, As is bonded to four O atoms to form AsO4 tetrahedra that share corners with two equivalent AlO4F2 octahedra. The corner-sharing octahedral tilt angles are 52°. There is three shorter (1.71 Å) and one longer (1.76 Å) As–O bond length. In the second As site, As is bonded to four O atoms to form AsO4 tetrahedra that share corners with two equivalent AlO4F2 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of As–O bond distances ranging from 1.69–1.74 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a water-like geometry to one Na and one As atom. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Al atoms. In the third O site, O is bonded in a distorted single-bond geometry to one Ca and one Al atom. In the fourth O site, O is bonded in a 4-coordinate geometry to one Na, two equivalent Ca, and one As atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Al and one As atom. In the sixth O site, O is bonded in a 4-coordinate geometry to one Na, two equivalent Ca, and one As atom. In the seventh O site, O is bonded in a 1-coordinate geometry to two equivalent Ca and one As atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one As atom. There are two inequivalent F sites. In the first F site, F is bonded in a 3-coordinate geometry to one Na, one Ca, and one Al atom. In the second F site, F is bonded in a distorted trigonal planar geometry to two equivalent Ca and one Al atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Chemo‐Mechanics Interplay Dictates Interface Instability and Asymmetry in Plating and Stripping of Sodium Metal Electrodes

Abstract The development of practical sodium (Na) metal batteries is hindered by key challenges including dendrite growth, dead metal formation, and unstable solid electrolyte interphase (SEI) growth. A fundamental understanding of the chemo‐mechanical interactions at the Na/SEI interface is critical for designing stable Na metal electrodes. In this work, the coupled electrochemical‐mechanical processes governing the morphological evolution and stability of Na metal during plating and stripping are investigated. The heterogeneous nature of transport and morphological interactions at the Na/SEI interface is revealed to result in nonuniform mechanical overpotentials and reaction fronts, eventually leading to Na filaments or pits. The spatio‐temporal evolution of stress heterogeneities during Na plating and stripping is shown to be asymmetric, manifesting in varying morphological nonuniformities and instability modes. The crucial role of external pressure in modulating the electrochemical‐transport interactions, the mechanical response of Na, and the localized reaction currents and stresses at the Na/SEI interface is demonstrated. At different external pressure conditions, the correlation between transport heterogeneities in the SEI and the onset and propagation of interface instability has been delineated. This work highlights the need for synergistic tailoring of external pressure and SEI heterogeneity toward achieving stable electrodeposition and dissolution in Na metal electrodes.

Singla, Aditya [School of Mechanical Engineering P↗
DOE OSTI2021

A Sodium–Antimony–Telluride Intermetallic Allows Sodium-Metal Cycling at 100% Depth of Discharge and as an Anode-Free Metal Battery

In this work, repeated cold rolling and folding is employed to fabricate a metallurgical composite of sodium–antimony–telluride Na 2 (Sb 2/6 Te 3/6 Vac 1/6 ) dispersed in electrochemically active sodium metal, termed “NST-Na.” This new intermetallic has a vacancy-rich thermodynamically stable face-centered-cubic structure and enables state-of-the-art electrochemical performance in widely employed carbonate and ether electrolytes. NST-Na achieves 100% depth-of-discharge (DOD) in 1 m NaPF 6 in G2, with 15 mAh cm –2 at 1 mA cm –2 and Coulombic efficiency (CE) of 99.4%, for 1000 h of plating/stripping. Sodium-metal batteries (SMBs) with NST-Na and Na 3 V 2 (PO 4 ) 3 (NVP) or sulfur cathodes give significantly improved energy, cycling, and CE (>99%). An anode-free battery with NST collector and NVP obtains 0.23% capacity decay per cycle. Imaging and tomography using conventional and cryogenic microscopy (Cryo-EM) indicate that the sodium metal fills the open space inside the self-supporting sodiophilic NST skeleton, resulting in dense (pore-free and solid electrolyte interphase (SEI)-free) metal deposits with flat surfaces. The baseline Na deposit consists of filament-like dendrites and “dead metal”, intermixed with pores and SEI. Density functional theory calculations show that the uniqueness of NST lies in the thermodynamic stability of the Na atoms (rather than clusters) on its surface that leads to planar wetting, and in its own stability that prevents decomposition during cycling.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Vacancy‐Enabled O3 Phase Stabilization for Manganese‐Rich Layered Sodium Cathodes

Abstract Manganese‐rich layered oxide materials hold great potential as low‐cost and high‐capacity cathodes for Na‐ion batteries. However, they usually form a P2 phase and suffer from fast capacity fade. In this work, an O3 phase sodium cathode has been developed out of a Li and Mn‐rich layered material by leveraging the creation of transition metal (TM) and oxygen vacancies and the electrochemical exchange of Na and Li. The Mn‐rich layered cathode material remains primarily O3 phase during sodiation/desodiation and can have a full sodiation capacity of ca. 220 mAh g −1 . It delivers ca. 160 mAh g −1 specific capacity between 2–3.8 V with >86 % retention over 250 cycles. The TM and oxygen vacancies pre‐formed in the sodiated material enables a reversible migration of TMs from the TM layer to the tetrahedral sites in the Na layer upon de‐sodiation and sodiation. The migration creates metastable states, leading to increased kinetic barrier that prohibits a complete O3‐P3 phase transition.

Xiao, Biwei↗
DOE OSTI2025

Lithium‐Containing Hybrid SEI Layer Enabling High Mass Loading and Anode‐Less Sodium Metal Batteries

Abstract The continuous rupturing and rebuilding of unstable solid electrolyte interphase (SEI) layer during cycling would block Na + diffusion and induce Na dendrite formation, ultimately limiting the practical application of high‐energy‐density sodium metal batteries. Herein, a hybrid SEI layer containing Li‐species is dexterously constructed on the surface of sodium metal anode. Li‐containing inorganic components (Li 3 N, LiF, and Li 2 CO 3 ) are introduced to stabilize the Na/electrolyte interface and enhance the mechanical and diffusion kinetic properties of the SEI layer, which can reduce the side reactions and gas generation, regulate Na + flux during cycling and promote rapid Na + migration for uniform dendrite‐free Na deposition. As a result, the constructed Na symmetric cells achieve low overpotential and long cycle life of 5900, 1800, and 500 h at current densities of 3, 10, and 30 mA cm −2 , respectively. Furthermore, the full cells paired with the Na₃V₂(PO₄)₃ cathode demonstrate high specific capacity and excellent cycle stability, even at an ultra‐high cathode loading of 39.3 mg cm −2 and a low N/P ratio (negative/positive electrode capacity ratio of 1.21).

Xia, Li [State Key Laboratory of Physical Chemistr↗
DOE OSTI2025

Lithium‐Containing Hybrid SEI Layer Enabling High Mass Loading and Anode‐Less Sodium Metal Batteries

The continuous rupturing and rebuilding of unstable solid electrolyte interphase (SEI) layer during cycling would block Na + diffusion and induce Na dendrite formation, ultimately limiting the practical application of high-energy-density sodium metal batteries. Herein, a hybrid SEI layer containing Li-species is dexterously constructed on the surface of sodium metal anode. Li-containing inorganic components (Li 3 N, LiF, and Li 2 CO 3 ) are introduced to stabilize the Na/electrolyte interface and enhance the mechanical and diffusion kinetic properties of the SEI layer, which can reduce the side reactions and gas generation, regulate Na + flux during cycling and promote rapid Na + migration for uniform dendrite-free Na deposition. As a result, the constructed Na symmetric cells achieve low overpotential and long cycle life of 5900, 1800, and 500 h at current densities of 3, 10, and 30 mA cm −2 , respectively. Furthermore, the full cells paired with the Na₃V₂(PO₄)₃ cathode demonstrate high specific capacity and excellent cycle stability, even at an ultra-high cathode loading of 39.3 mg cm −2 and a low N/P ratio (negative/positive electrode capacity ratio of 1.21).

Diffusion kinetic↗
DOE OSTI2024

Self‐Templated 3D Sulfide‐Based Solid Composite Electrolyte for Solid‐State Sodium Metal Batteries

Abstract Rechargeable solid‐state sodium metal batteries (SSMBs) experience growing attention owing to the increased energy density (vs Na‐ion batteries) and cost‐effective materials. Inorganic sulfide‐based Na‐ion conductors also possess significant potential as promising solid electrolytes (SEs) in SSMBs. Nevertheless, due to the highly reactive Na metal, poor interface compatibility is the biggest obstacle for inorganic sulfide solid electrolytes such as Na 3 SbS 4 to achieve high performance in SSMBs. To address such electrochemical instability at the interface, new design of sulfide SE nanostructures and interface engineering are highly essential. In this work, a facile and straightforward approach is reported to prepare 3D sulfide‐based solid composite electrolytes (SCEs), which utilize porous Na 3 SbS 4 (NSS) as a self‐templated framework and fill with a phase transition polymer. The 3D structured SCEs display obviously improved interface stability toward Na metal than pristine sulfide. The assembled SSMBs (with TiS 2 or FeS 2 as cathodes) deliver outstanding electrochemical cycling performance. Moreover, the cycling of high‐voltage oxide cathode Na 0.67 Ni 0.33 Mn 0.67 O 2 (NNMO) is also demonstrated in SSMBs using 3D sulfide‐based SCEs. This study presents a novel design on the self‐templated nanostructure of SCEs, paving the way for the advancement of high‐energy sodium metal batteries.

Guo, Xiaolin↗
DOE OSTI2020

Long-range transported North American wildfire aerosols observed in marine boundary layer of eastern North Atlantic

Wildfire is a major source of biomass burning aerosols, which greatly impact Earth climate. Tree species in North America (NA) boreal forests can support high-intensity crown fires, resulting in elevated injection height and longer lifetime (on the order of months) of the wildfire aerosols. Given the long lifetime, the properties of aged NA wildfire aerosols are required to understand and quantify their effects on radiation and climate. Here we present comprehensive characterization of climatically relevant properties, including optical properties and cloud condensation nuclei (CCN) activities of aged NA wildfire aerosols, emitted from the record-breaking Canadian wildfires in August 2017. Despite the extreme injection height of ~12 km, some of the wildfire plumes descended into the marine boundary layer in the eastern North Atlantic over a period of ~2 weeks, owing to the dry intrusions behind mid-latitude cyclones. The aged wildfire aerosols have high single scattering albedos at 529 nm (ω 529 ; 0.92–0.95) while low absorption Ångström exponents (Å abs ) at 464 nm/648 nm (0.7–0.9). In comparison, Å abs of fresh/slightly aged ones are typically 1.4–3.5. This low Å abs 529 and low Å abs ~110 nm diameter) with thick non-absorbing coatings. The accelerated descent of the wildfire plume also led to strong increase of CCN concentration at the supersaturation levels representative of marine low clouds. The hygroscopicity parameter, κ CCN , of the aged wildfire aerosols varies from 0.2 to 0.4, substantially lower than that of background marine boundary layer aerosols. However, the high fraction of particles with large diameter (i.e., within accumulation size ranges, ~100–250 nm) compensates for the low values of κ, and as a result, the aged NA wildfire aerosols contribute more efficiently to CCN population. These results provide direct evidence that the long-range transported NA wildfires can strongly influence CCN concentration in remote marine boundary layer, therefore the radiative properties of marine low clouds. Given the expected increases of NA wildfire intensity and frequency and regular occurrence of dry intrusion following mid-latitude cyclones, the influence of NA wildfire aerosols on CCN and clouds in remote marine environment need to be further examined.

54 ENVIRONMENTAL SCIENCES↗