Search NASA⌕ Search

SEARCH · Search NASA

Results for “NaNbO3”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Na1+ is bonded to twelve equivalent O2- atoms to form NaO12 cuboctahedra that share corners with twelve equivalent NaO12 cuboctahedra, faces with six equivalent NaO12 cuboctahedra, and faces with eight equivalent NbO6 octahedra. All Na–O bond lengths are 2.84 Å. Nb5+ is bonded to six equivalent O2- atoms to form NbO6 octahedra that share corners with six equivalent NbO6 octahedra and faces with eight equivalent NaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Nb–O bond lengths are 2.00 Å. O2- is bonded in a distorted linear geometry to four equivalent Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is Orthorhombic Perovskite-like structured and crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 3-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.91 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.47–2.69 Å. Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 18–30°. There are a spread of Nb–O bond distances ranging from 1.90–2.19 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.55 Å) and four longer (2.79 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.55 Å) and four longer (2.79 Å) Na–O bond lengths. Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–23°. All Nb–O bond lengths are 2.01 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is Ilmenite-like structured and crystallizes in the trigonal R3c space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. There are three shorter (2.44 Å) and three longer (2.55 Å) Na–O bond lengths. Nb5+ is bonded to six equivalent O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 25°. There are three shorter (1.91 Å) and three longer (2.16 Å) Nb–O bond lengths. O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.46–2.68 Å. In the second Na1+ site, Na1+ is bonded in a 3-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.84 Å. Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 17–29°. There are a spread of Nb–O bond distances ranging from 1.89–2.21 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 12-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.42–2.78 Å. In the second Na1+ site, Na1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Na–O bond distances ranging from 2.57–2.97 Å. Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 18–26°. All Nb–O bond lengths are 2.01 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is Orthorhombic Perovskite-like structured and crystallizes in the orthorhombic Pca2_1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.43–2.86 Å. In the second Na1+ site, Na1+ is bonded in a 3-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.72 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 23–26°. There are a spread of Nb–O bond distances ranging from 1.91–2.16 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 12–31°. There are a spread of Nb–O bond distances ranging from 1.91–2.16 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to one Na1+ and two Nb5+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbO3 by Materials Project

NaNbO3 is (Cubic) Perovskite-like structured and crystallizes in the orthorhombic P222_1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.75–2.93 Å. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.79–2.88 Å. In the third Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.72–2.96 Å. In the fourth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.75–2.95 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with eight NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Nb–O bond distances ranging from 1.90–2.13 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with eight NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–12°. There are a spread of Nb–O bond distances ranging from 1.92–2.11 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Tunable phase structure in NaNbO 3 ceramics by grain-size effect, electric field and heat treatment

Large polarization and strain change during antiferroelectric - ferroelectric phase transition under electric field is the foundation for realizing excellent electrical properties in antiferroelectric ceramics, therefore, the adjustment of antiferroelectricity and clarification of the corresponding mechanism is the foundation for controlling electrical properties. NaNbO3 is the most complex perovskite system showing multiple antiferroelectric phases in a wide temperature range, in which the antiferroelectricity shows obvious instability with changing external and internal conditions, namely the antiferroelectric phase can be adjusted by grain-size effect, electric field and heat treatment. According to the systematical study in terms of the Rietveld refinement of synchrotron XRD and Raman, NaNbO3 exhibits a ferrielectric P21ma structure at room temperature, the ferroelectric component of which increases with decreasing grain size. Two antiferroelectric tetragonal phases exist around Curie temperature TC before the entrance of antiferroelectric R phase zone, while an antiferroelectric monoclinic phase, which can be maintained to room temperature by annealing treatment, acts as the bridge for the depolarization of the poled NaNbO3 with ferroelectric Q phase. A detailed phase diagram mainly focused on the antiferroelectric phase zones of NaNbO3 is plotted, which gives a clear understanding about the polymorphic phase transitions under different conditions. Finally, the results concluded in this work would give a clear guidance for designing high-performance NaNbO3-based lead-free ceramics from the point of structure.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Deterministic Fabrication of Large-Area, High-Crystallinity Oxide Moiré Superlattices

Oxide twistronics extends moiré engineering beyond van der Waals materials, offering a promising platform for accessing emergent interfacial phenomena arising from the strong coupling of lattice, charge, and orbital degrees of freedom in complex oxides. However, deterministic fabrication of high-crystallinity oxide moiré superlattices over large lateral dimensions remains challenging due to the three-dimensional bonding network of oxides. Here, we demonstrate a scalable, generalized fabrication strategy that enables the formation of high-crystallinity oxide moiré superlattices with clean, chemically bonded interfaces and precisely controlled twist angles down to nominal values of 0.1°, achieving subdegree twist-angle accuracy across large contiguous lateral dimensions approaching the millimeter scale. Using NaNbO3 as a model system, we show that the resulting interlayer coupling drives pronounced structural reconstruction that modifies both the phase structure and ferroelectric domain configuration. Synchrotron-based X-ray 3D reciprocal space mapping reveals the emergence of a single-phase state in twisted bilayers, in contrast to the mixed-phase structure observed in single-layer membranes prior to twist assembly. The structural signatures are further consistent with gradual lattice rotation distributed along the thickness direction that may accommodate interfacial shear strain, distinct from reconstruction observed in van der Waals moiré systems which primarily occurs through in-plane stacking rearrangement. This collective lattice response is correlated with twist-dependent nanoscale electromechanical modulations observed by piezoresponse force microscopy. These results establish a scalable materials platform for oxide twistronics and support the implementation of twist-engineered functionalities in practical, macroscale device architectures.

Ghanbari, Reza [North Carolina State University (N↗
NASA NTRS1974

Alkali oxide-tantalum oxide and alkali oxide-niobium oxide ionic conductors

A search was made for new cationic conducting phases in alkali-tantalate and niobate systems. The phase equilibrium diagrams were constructed for the six binary systems Nb2O5-LiNbO3, Nb2O5-NaNbO3, Nb2O5-KNbO3, Ta2O5-NaTaO3, Ta2O5-LiTaO3, and Ta2O5-KTaO3. Various other binary and ternary systems were also examined. Pellets of nineteen phases were evaluated (by the sponsoring agency) by dielectric loss measurements. Attempts were made to grow large crystals of eight different phases. The system Ta2O5-KTaO3 contains at least three phases which showed peaks in dielectric loss vs. temperature. All three contain structures related to the tungsten bronzes with alkali ions in non-stoichiometric crystallographic positions.

Roth, R. S.↗