Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Bi-Ni”

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.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Superconducting phase diagram in Bi x Ni 1 – x thin films: The effects of Bi stoichiometry on superconductivity

The Bi-Ni binary system has been of interest due to possible unconventional superconductivity aroused therein, such as time-reversal symmetry breaking in Bi/Ni bilayers or the coexistence of superconductivity and ferromagnetism in Bi 3 ⁢Ni crystals. While Ni acts as a ferromagnetic element in such systems, the role of the strong spin-orbit coupling element Bi in superconductivity has remained unexplored. In this work, we systematically studied the effects of Bi stoichiometry on the superconductivity of Bi x ⁢Ni 1–x thin films (x ≈ 0.5–0.9) fabricated via a composition-spread approach. Here, the superconducting phase map of Bi x ⁢Ni 1–x thin films exhibited a superconducting composition region attributable to the intermetallic Bi 3 ⁢Ni phase with different amounts of excess Bi, revealed by synchrotron x-ray diffraction analysis. Interestingly, the mixed-phase region with Bi 3 ⁢Ni and Bi showed unusual increases in the superconducting transition temperature and residual resistance ratio as more Bi impurities were included, with the maximum T c (=4.2K) observed at x ≈ 0.79. A correlation analysis of structural, electrical, and magneto-transport characteristics across the composition variation revealed that the unusual superconducting “dome” is due to two competing roles of Bi: impurity scattering and carrier doping. We found that the carrier doping effect is dominant in the mild doping regime (0.74 ≤ x ≤ 0.79), while impurity scattering becomes more pronounced at larger Bi stoichiometry.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on NiBi by Materials Project

NiBi is Tungsten Carbide-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ni is bonded to six equivalent Bi atoms to form a mixture of distorted corner and edge-sharing NiBi6 pentagonal pyramids. All Ni–Bi bond lengths are 2.75 Å. Bi is bonded to six equivalent Ni atoms to form a mixture of corner, edge, and face-sharing BiNi6 octahedra. The corner-sharing octahedral tilt angles are 44°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiBi3 by Materials Project

NiBi3 crystallizes in the orthorhombic Pnma space group. The structure is one-dimensional and consists of two NiBi3 ribbons oriented in the (1, 0, 0) direction. Ni is bonded in a 9-coordinate geometry to two equivalent Ni and seven Bi atoms. Both Ni–Ni bond lengths are 2.65 Å. There are a spread of Ni–Bi bond distances ranging from 2.73–2.79 Å. There are three inequivalent Bi sites. In the first Bi site, Bi is bonded in a single-bond geometry to one Ni atom. In the second Bi site, Bi is bonded in a 3-coordinate geometry to three equivalent Ni atoms. In the third Bi site, Bi is bonded in a 3-coordinate geometry to three equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ni3Bi by Materials Project

Ni3Bi is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Ni is bonded to eight equivalent Ni and four equivalent Bi atoms to form NiNi8Bi4 cuboctahedra that share corners with twelve equivalent NiNi8Bi4 cuboctahedra, edges with eight equivalent BiNi12 cuboctahedra, edges with sixteen equivalent NiNi8Bi4 cuboctahedra, faces with four equivalent BiNi12 cuboctahedra, and faces with fourteen equivalent NiNi8Bi4 cuboctahedra. All Ni–Ni bond lengths are 2.70 Å. All Ni–Bi bond lengths are 2.70 Å. Bi is bonded to twelve equivalent Ni atoms to form BiNi12 cuboctahedra that share corners with twelve equivalent BiNi12 cuboctahedra, edges with twenty-four equivalent NiNi8Bi4 cuboctahedra, faces with six equivalent BiNi12 cuboctahedra, and faces with twelve equivalent NiNi8Bi4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiBi by Materials Project

NiBi crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ni is bonded in a distorted body-centered cubic geometry to two equivalent Ni and six equivalent Bi atoms. Both Ni–Ni bond lengths are 2.65 Å. All Ni–Bi bond lengths are 2.75 Å. Bi is bonded in a 6-coordinate geometry to six equivalent Ni atoms.

36 MATERIALS SCIENCE↗