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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 721 records · Page 40
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on NpH3 by Materials Project

NpH3 crystallizes in the trigonal P-3c1 space group. The structure is three-dimensional. Np3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Np–H bond distances ranging from 2.14–2.43 Å. There are three inequivalent H1- sites. In the first H1- site, H1- is bonded in a trigonal non-coplanar geometry to three equivalent Np3+ atoms. In the second H1- site, H1- is bonded to four equivalent Np3+ atoms to form a mixture of distorted corner, edge, and face-sharing HNp4 tetrahedra. In the third H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Np3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpPt3 by Materials Project

NpPt3 is beta Cu3Ti-like structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Np6+ is bonded to twelve Pt2- atoms to form a mixture of face and corner-sharing NpPt12 cuboctahedra. There are a spread of Np–Pt bond distances ranging from 2.87–3.01 Å. There are two inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a distorted see-saw-like geometry to four equivalent Np6+ atoms. In the second Pt2- site, Pt2- is bonded in a distorted see-saw-like geometry to four equivalent Np6+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpRuO3 by Materials Project

NpRuO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Np3+ is bonded to twelve equivalent O2- atoms to form NpO12 cuboctahedra that share corners with twelve equivalent NpO12 cuboctahedra, faces with six equivalent NpO12 cuboctahedra, and faces with eight equivalent RuO6 octahedra. All Np–O bond lengths are 2.80 Å. Ru3+ is bonded to six equivalent O2- atoms to form RuO6 octahedra that share corners with six equivalent RuO6 octahedra and faces with eight equivalent NpO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ru–O bond lengths are 1.98 Å. O2- is bonded in a distorted linear geometry to four equivalent Np3+ and two equivalent Ru3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na3Np6FeF30 by Materials Project

Na3Np6FeF30 crystallizes in the trigonal P-3c1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted octahedral geometry to six F1- atoms. There are three shorter (2.28 Å) and three longer (2.34 Å) Na–F bond lengths. In the second Na1+ site, Na1+ is bonded to twelve F1- atoms to form NaF12 cuboctahedra that share faces with two equivalent FeF6 octahedra. There are six shorter (2.61 Å) and six longer (2.71 Å) Na–F bond lengths. Np4+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Np–F bond distances ranging from 2.28–2.44 Å. Fe3+ is bonded to six equivalent F1- atoms to form FeF6 octahedra that share faces with two equivalent NaF12 cuboctahedra. All Fe–F bond lengths are 1.94 Å. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to one Na1+ and two equivalent Np4+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to one Na1+ and two equivalent Np4+ atoms. In the third F1- site, F1- is bonded in a 3-coordinate geometry to one Na1+ and two equivalent Np4+ atoms. In the fourth F1- site, F1- is bonded in a 3-coordinate geometry to one Na1+, one Np4+, and one Fe3+ atom. In the fifth F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Np4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Np2C3 by Materials Project

Np2C3 is Plutonium carbide structured and crystallizes in the cubic I-43d space group. The structure is three-dimensional. Np3+ is bonded in a 6-coordinate geometry to six equivalent C2- atoms. There are three shorter (2.44 Å) and three longer (2.53 Å) Np–C bond lengths. C2- is bonded to four equivalent Np3+ and one C2- atom to form a mixture of distorted corner and edge-sharing CNp4C trigonal bipyramids. The C–C bond length is 1.42 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KNpO3 by Materials Project

KNpO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. K1+ is bonded to twelve equivalent O2- atoms to form KO12 cuboctahedra that share corners with twelve equivalent KO12 cuboctahedra, faces with six equivalent KO12 cuboctahedra, and faces with eight equivalent NpO6 octahedra. All K–O bond lengths are 3.04 Å. Np5+ is bonded to six equivalent O2- atoms to form NpO6 octahedra that share corners with six equivalent NpO6 octahedra and faces with eight equivalent KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Np–O bond lengths are 2.15 Å. O2- is bonded in a distorted linear geometry to four equivalent K1+ and two equivalent Np5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Np2CoH8F10 by Materials Project

(NpF5)2CoH6H2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four hydrogen molecules; two CoH6 clusters; and one NpF5 sheet oriented in the (0, 0, 1) direction. In each CoH6 cluster, Co2+ is bonded in an octahedral geometry to six H+0.25+ atoms. There is two shorter (1.53 Å) and four longer (1.57 Å) Co–H bond length. There are three inequivalent H+0.25+ sites. In the first H+0.25+ site, H+0.25+ is bonded in a 2-coordinate geometry to one Co2+ and one H+0.25+ atom. The H–H bond length is 0.90 Å. In the second H+0.25+ site, H+0.25+ is bonded in a single-bond geometry to one Co2+ atom. In the third H+0.25+ site, H+0.25+ is bonded in a 2-coordinate geometry to one Co2+ and one H+0.25+ atom. In the NpF5 sheet, Np3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Np–F bond distances ranging from 2.05–2.56 Å. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Np3+ atom. In the second F1- site, F1- is bonded in a 1-coordinate geometry to two equivalent Np3+ atoms. In the third F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two equivalent Np3+ atoms. In the fourth F1- site, F1- is bonded in a bent 120 degrees geometry to two equivalent Np3+ atoms. In the fifth F1- site, F1- is bonded in a bent 120 degrees geometry to two equivalent Np3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpH3 by Materials Project

NpH3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Np3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Np–H bond distances ranging from 2.14–2.38 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Np3+ atoms. In the second H1- site, H1- is bonded to four equivalent Np3+ atoms to form a mixture of corner, edge, and face-sharing HNp4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpTe3 by Materials Project

NpTe3 crystallizes in the orthorhombic Cmcm space group. The structure is two-dimensional and consists of two NpTe3 sheets oriented in the (0, 1, 0) direction. Np6+ is bonded in a 9-coordinate geometry to nine Te2- atoms. There are a spread of Np–Te bond distances ranging from 3.19–3.24 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 5-coordinate geometry to five equivalent Np6+ atoms. In the second Te2- site, Te2- is bonded in a 2-coordinate geometry to two equivalent Np6+ and four equivalent Te2- atoms. All Te–Te bond lengths are 3.07 Å. In the third Te2- site, Te2- is bonded in a 2-coordinate geometry to two equivalent Np6+ and four equivalent Te2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpB4 by Materials Project

NpB4 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Np6+ is bonded in a 12-coordinate geometry to eighteen B+1.50- atoms. There are a spread of Np–B bond distances ranging from 2.70–3.00 Å. There are three inequivalent B+1.50- sites. In the first B+1.50- site, B+1.50- is bonded in a distorted trigonal planar geometry to six equivalent Np6+ and three B+1.50- atoms. There is two shorter (1.69 Å) and one longer (1.74 Å) B–B bond length. In the second B+1.50- site, B+1.50- is bonded in a 1-coordinate geometry to four equivalent Np6+ and five B+1.50- atoms. There is one shorter (1.60 Å) and four longer (1.76 Å) B–B bond length. In the third B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Np6+ and five B+1.50- atoms. Both B–B bond lengths are 1.82 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Np2O3 by Materials Project

Np2O3 is Corundum structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Np3+ is bonded to six equivalent O2- atoms to form a mixture of distorted face, edge, and corner-sharing NpO6 pentagonal pyramids. There are three shorter (2.32 Å) and three longer (2.39 Å) Np–O bond lengths. O2- is bonded to four equivalent Np3+ atoms to form a mixture of distorted edge and corner-sharing ONp4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KNp(CO3)2 by Materials Project

KNp(CO3)2 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of two KNp(CO3)2 sheets oriented in the (1, 0, 0) direction. K1+ is bonded to six O2- atoms to form edge-sharing KO6 octahedra. There are four shorter (2.88 Å) and two longer (2.90 Å) K–O bond lengths. Np3+ is bonded in a distorted linear geometry to two equivalent O2- atoms. Both Np–O bond lengths are 1.84 Å. C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.25 Å) and one longer (1.27 Å) C–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one Np3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one C4+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one C4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpHgO3 by Materials Project

NpHgO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Np4+ is bonded to six equivalent O2- atoms to form NpO6 octahedra that share corners with six equivalent NpO6 octahedra and faces with eight equivalent HgO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Np–O bond lengths are 2.13 Å. Hg2+ is bonded to twelve equivalent O2- atoms to form HgO12 cuboctahedra that share corners with twelve equivalent HgO12 cuboctahedra, faces with six equivalent HgO12 cuboctahedra, and faces with eight equivalent NpO6 octahedra. All Hg–O bond lengths are 3.02 Å. O2- is bonded in a linear geometry to two equivalent Np4+ and four equivalent Hg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsNpO3 by Materials Project

CsNpO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Cs1+ is bonded to twelve equivalent O2- atoms to form CsO12 cuboctahedra that share corners with twelve equivalent CsO12 cuboctahedra, faces with six equivalent CsO12 cuboctahedra, and faces with eight equivalent NpO6 octahedra. All Cs–O bond lengths are 3.10 Å. Np5+ is bonded to six equivalent O2- atoms to form NpO6 octahedra that share corners with six equivalent NpO6 octahedra and faces with eight equivalent CsO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Np–O bond lengths are 2.20 Å. O2- is bonded in a distorted linear geometry to four equivalent Cs1+ and two equivalent Np5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NpUP4H4(CO8)2 by Materials Project

NpUP4H4(CO8)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Np4+ is bonded in a 1-coordinate geometry to eight O2- atoms. There are a spread of Np–O bond distances ranging from 1.81–2.46 Å. U4+ is bonded to six O2- atoms to form UO6 octahedra that share corners with four PCO3 tetrahedra. There are a spread of U–O bond distances ranging from 1.81–2.37 Å. C is bonded in a distorted tetrahedral geometry to two P5+ and two H1+ atoms. There is one shorter (1.79 Å) and one longer (1.81 Å) C–P bond length. Both C–H bond lengths are 1.10 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one C and three O2- atoms to form PCO3 tetrahedra that share a cornercorner with one UO6 octahedra and a cornercorner with one PCO3 tetrahedra. The corner-sharing octahedral tilt angles are 33°. There are a spread of P–O bond distances ranging from 1.52–1.56 Å. In the second P5+ site, P5+ is bonded to one C and three O2- atoms to form distorted PCO3 tetrahedra that share a cornercorner with one UO6 octahedra and a cornercorner with one PCO3 tetrahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C atom. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Np4+ and one P5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to one U4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Np4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one U4+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Np4+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one Np4+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Np4+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U4+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Reconstructing Oxygen-Deficient Zirconia with Ruthenium Catalyst on Atomic-Scale Interfaces toward Hydrogen Production

Downsizing a catalyst nanoparticle (NP) to a single atom (SA) has proven to be highly effective in increasing catalytic activity and decreasing the amount of catalyst required for various electrochemical reactions. However, insufficient stability of the single-atom site catalysts (SACs) is still a significant challenge for their practical application. Here, SACs firmly bound to stable metal oxide NPs are proposed to dramatically increase the electrochemical activity and stability of SA-based catalysts for hydrogen evolution reaction (HER). Starting from a Ru-infiltrated, Zr-based metal-organic framework (MOF), the tetragonal zirconium oxide (ZrO 2-x ) NPs-embedded carbon matrix is fabricated as support through facile pyrolysis. Simultaneously, Ru SAs as active sites are well dispersed on the surface of ZrO 2-x NPs due to the generation of oxygen vacancies in the tetragonal ZrO 2-x . Finally, the Ru-ZrO 2-x SAC exhibits a 4–5 times higher mass activity than commercial Pt and Ru catalysts and superior durability due to strong metal-support interaction (SMSI) between Ru atoms and ZrO 2-x substrate.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Low Thermal Conductivity and Diffusivity at High Temperatures Using Stable High–Entropy Spinel Oxide Nanoparticles

The realization of low thermal conductivity at high temperatures (0.11 W m –1 K –1 800 °C) in ambient air in a porous solid thermal insulation material, using stable packed nanoparticles of high-entropy spinel oxide with 8 cations (HESO-8 NPs) with a relatively high packing density of ≈50%, is reported. The high-density HESO-8 NP pellets possess around 1000-fold lower thermal diffusivity than that of air, resulting in much slower heat propagation when subjected to a transient heat flux. The low thermal conductivity and diffusivity are realized by suppressing all three modes of heat transfer, namely solid conduction, gas conduction, and thermal radiation, via stable nanoconstriction and infrared-absorbing nature of the HESO-8 NPs, which are enabled by remarkable microstructural stability against coarsening at high temperatures due to the high entropy. Furthermore, this work can elucidate the design of the next-generation high-temperature thermal insulation materials using high-entropy ceramic nanostructures.

thermal insulation↗
DOE OSTI2024

Engineering Ultrathin Alloy Shell in Au@AuPd Core-Shell Nanoparticles for Efficient Plasmon-Driven Photocatalysis

Bimetallic core-shell nanoparticles (NPs) possessing a synergetic coupling of plasmonic and catalytic metals have emerged as promising prototypes for efficient plasmon-driven photocatalysis. Here, Au@AuPd core-shell NPs composed of Au core NP and ultrathin AuPd shell are introduced to acquire improved light utilization efficiency in photocatalytic selective oxidation. With systematical control of the composition of the ultrathin alloy shell, it reveals that the Au@AuPd core-shell NPs with 10 at% Pd (in the single-atom alloy regime) is an effective nanostructure capable of maximizing the quantum yield of plasmon-induced light absorption and optimizing the surface electronic structure for catalytic reactions. This controlled system provides new insights into shell engineering for enhancing photocatalytic performance via the regulation of energy funneling processes in core-shell nanocatalysts.

36 MATERIALS SCIENCE↗