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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 757 records · Page 42
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Conference Support for CU*IP at UCONN

This award supported six students to attend the national Conference for Undergraduate Women and Gender Minorities in Physics (CU*IP) held at the University of Connecticut on January 24-26, 2025. The CU*IP conference series provides opportunities for under-represented undergraduate students to obtain real conference experience, hear from role models in the field of physics, and to network with their peers. The funds will support travel, lodging, and meal expenses for students otherwise not able to attend the meeting.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2021

In Situ Recrystallization of Co-Evaporated Cu(In,Ga)Se2 Thin Films by Copper Chloride Vapor Treatment towards Solar Cell Applications

Cu(In,Ga)Se2 (or CIGS) thin films and devices were fabricated using a modified three-stage process. Using high deposition rates and a low temperature during the process, a copper chloride vapor treatment was introduced in between the second and third stages to enhance the films properties. X-ray diffraction and scanning electron microscopy demonstrate that drastic changes occur after this recrystallization process, yielding films with much larger grains. Secondary ion mass spectrometry shows that the depth profile of many elements is not modified (such as Cu, In and Se) while others change dramatically (such as Ga and Na). Because of the competing effects of these changes, not all parameters of the solar cells are enhanced, yielding an increase of 15% in the device efficiency at the most.

14 SOLAR ENERGY↗
DOE OSTI2022

Reduction of Chlorinated Ethenes by Ag- and Cu-Amended Green Rust

Chlorinated ethenes have been used extensively as solvents, degreasers, and dry-cleaning agents in a range of commercial and industrial applications. This has created a legacy of contaminated soils and groundwater, particularly with respect to perchloroethylene (PCE; a.k.a. tetrachloroethene—C 2 Cl 4 ), and trichloroethylene (TCE; a.k.a. trichloroethene—C 2 HCl 3 ), prompting the development of a wide array of treatment technologies for remediation of chlorinated ethene-contaminated environments. Green rusts are highly redox-active layered Fe(II)-Fe(III) hydroxides that have been shown to be facile reductants for a wide range of organic and inorganic pollutants. The reduction of chlorinated ethenes [vinyl chloride (VC); 1,1-dichloroethene(11DCE), cis-1,2-dichloroethene (c12DCE), trans-1,2-dichloroethene (t12DCE), TCE, and PCE] was examined in aqueous suspensions of green rust, alone as well as with the addition of Ag(I) (AgGR) or Cu(II) (CuGR). Green rust alone was ineffective as a reductant for the reductive dechlorination for all of the chlorinated ethenes. Near-complete removal of PCE was observed in the presence of AgGR, but all other chlorinated ethenes were essentially non-reactive. Partial removal of chlorinated ethenes was observed in the presence of CuGR, particularly 11DCE (34%), t12DCE (51%), and VC (66%). Significant differences were observed in the product distributions of chlorinated ethene reduction by AgGR and CuGR. The effectiveness of Ag(I)- and Cu(II)-amended green rusts for removal of chlorinated ethenes may be improved under different conditions (e.g., pH and interlayer anion) and warrants further investigation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Combinatorial Cu-Ni Alloy Thin-Film Catalysts for Layer Number Control in Chemical Vapor-Deposited Graphene

We synthesized a combinatorial library of CuxNi1−x alloy thin films via co-sputtering from Cu and Ni targets to catalyze graphene chemical vapor deposition. The alloy morphology, composition, and microstructure were characterized via scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and X-ray diffraction (XRD), respectively. Subsequently, the CuxNi1−x alloy thin films were used to grow graphene in a CH4-Ar-H2 ambient at atmospheric pressure. The underlying rationale is to adjust the CuxNi1−x composition to control the graphene. Energy dispersive x-ray spectroscopy (EDS) analysis revealed that a continuous gradient of CuxNi1−x (25 at. % < x < 83 at.%) was initially achieved across the 100 mm diameter substrate (~0.9%/mm composition gradient). The XRD spectra confirmed a solid solution was realized and the face-centered cubic lattice parameter varied from ~3.52 to 3.58 A˙, consistent with the measured composition gradient, assuming Vegard’s law. Optical microscopy and Raman analysis of the graphene layers suggest single layer growth occurs with x > 69 at.%, bilayer growth dominates from 48 at.% < x < 69 at.%, and multilayer (≥3) growth occurs for x < 48 at.%, where x is the Cu concentration. Finally, a large area of bi-layer graphene was grown via a CuxNi1−x catalyst with optimized catalyst composition and growth temperature.

2D materials↗
DOE OSTI2023

Thermal and Radiation Stability in Nanocrystalline Cu

Nanocrystalline metals have presented intriguing possibilities for use in radiation environments due to their high grain boundary volume, serving as enhanced irradiation-induced defect sinks. Their promise has been lessened due to the propensity for nanocrystalline metals to suffer deleterious grain growth from combinations of irradiation and/or elevated homologous temperature. While approaches for stabilizing such materials against grain growth are the subject of current research, there is still a lack of central knowledge on the irradiation–grain boundary interactions in pure metals despite many studies on the same. Due to the breadth of available reports, we have critically reviewed studies on irradiation and thermal stability in pure, nanocrystalline copper (Cu) as a model FCC material, and on a few dilute Cu-based alloys. Our study has shown that, viewed collectively, there are large differences in interpretation of irradiation–grain boundary interactions, primarily due to a wide range of irradiation environments and variability in materials processing. We discuss the sources of these differences and analyses herein. Then, with the goal of gaining a more overarching mechanistic understanding of grain size stability in pure materials under irradiation, we provide several key recommendations for making meaningful evaluations across materials with different processing and under variable irradiation conditions.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Applications of LIF to Document Natural Variability of Chlorophyll Content and Cu Uptake in Moss

Chlorophyll has long been used as a natural indicator of plant health and photosynthetic efficiency. Laser-induced fluorescence (LIF) is an emerging technique for understanding broad spectrum organic processes and has more recently been used to monitor chlorophyll response in plants. Previous work has focused on developing a LIF technique for imaging moss mats to identify metal contamination with the current focus shifting toward application to moss fronds and aiding sample collection for chemical analysis. Two laser systems (CoCoBi a Nd:YGa pulsed laser system and Chl-SL with two blue continuous semiconductor diodes) were used to collect images of moss fronds exposed to increasing levels of Cu (1, 10, and 100 nmol/cm 2 ) using a CMOS camera. The best methods for the preprocessing of images were conducted before the analysis of fluorescence signatures were compared to a control. The Chl-SL system performed better than the CoCoBi, with dynamic time warping (DTW) proving the most effective for image analysis. Manual thresholding to remove lower decimal code values improved the data distributions and proved whether using one or two fronds in an image was more advantageous. A higher DTW difference from the control correlated to lower chlorophyll a/b ratios and a higher metal content, indicating that LIF, with the aid of image processing, can be an effective technique for identifying Cu contamination shortly after an event.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

Development and Reliability of Screen-Printable Fire-Through Cu Paste for Passivated Contact Solar Cells

We present the development of copper (Cu) paste which has been screen printed on Selective Emitter-Passivated Emitter Rear Contact (SE-PERC) solar cells. This paste can also be applied to Tunnel Oxide Passivated Contact (TOPCON) solar cells due to its fire-through nature. Champion PERC cells have achieved ....efficiency with ...parameters . Accelerated testing to investigate reliability performance of the SE- PERC mini-modules were carried out in damp heat chamber with 85oC and 85% humidity. The devices were found to be operational even after 1,500 hours. Devices with screen printed Ag contacts on the front side have been studied in parallel to the Cu contacts for comparison.

copper paste↗
DOE OSTI2024

Preparation and Characterization of YBa 2 Cu 4 O 8 Superconductor

Solid-state reaction of appropriate amounts of Y 2 O 3 , BaCOs, and CuO for 2 h at 800°C in flowing oxygen with a total pressure of 2.7 x 10 2 Pa (2 mm Hg), followed by cooling and annealing at 750°C for 10 h in oxygen at ambient pressure, has produced orthorhombic YBa 2 Cu 4 O 8 (124) as the main phase with YBa 2 Cu 3 O x (123) as an impurity phase. After the as-calcined powder was annealed in oxygen at 800°C for 24 h under ambient pressure, the phase purity improved considerably. Calcined 124 powder was pressed into pellets and rapidly annealed at temperatures from 870°C to 935°C. At these temperatures, the 124 decomposed into 123. The superconducting transition temperature, T c , of the annealed samples depended upon the annealing temperature and atmosphere. The decomposed samples have been characterized by low field RF SQUID magnetometer and high resolution transmission electron microscopy.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(IrS2)2 by Materials Project

CuIr2S4 is Spinel structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Ir+3.50+ is bonded to six equivalent S2- atoms to form IrS6 octahedra that share corners with six equivalent CuS4 tetrahedra and edges with six equivalent IrS6 octahedra. All Ir–S bond lengths are 2.38 Å. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with twelve equivalent IrS6 octahedra. The corner-sharing octahedra tilt angles range from 57–59°. All Cu–S bond lengths are 2.33 Å. S2- is bonded to three equivalent Ir+3.50+ and one Cu1+ atom to form a mixture of distorted edge and corner-sharing SCuIr3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(RhS2)2 by Materials Project

CuRh2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Rh+3.50+ is bonded to six equivalent S2- atoms to form RhS6 octahedra that share corners with six equivalent CuS4 tetrahedra and edges with six equivalent RhS6 octahedra. All Rh–S bond lengths are 2.38 Å. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with twelve equivalent RhS6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Cu–S bond lengths are 2.30 Å. S2- is bonded to three equivalent Rh+3.50+ and one Cu1+ atom to form a mixture of distorted edge and corner-sharing SCuRh3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(RhSe2)2 by Materials Project

CuRh2Se4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Rh+3.50+ is bonded to six equivalent Se2- atoms to form RhSe6 octahedra that share corners with six equivalent CuSe4 tetrahedra and edges with six equivalent RhSe6 octahedra. All Rh–Se bond lengths are 2.51 Å. Cu1+ is bonded to four equivalent Se2- atoms to form CuSe4 tetrahedra that share corners with twelve equivalent RhSe6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Cu–Se bond lengths are 2.42 Å. Se2- is bonded to three equivalent Rh+3.50+ and one Cu1+ atom to form a mixture of distorted edge and corner-sharing SeCuRh3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(AsO2)2 by Materials Project

CuAs2O4 crystallizes in the tetragonal P4_2/mbc space group. The structure is three-dimensional. Cu1+ is bonded to six O2- atoms to form distorted edge-sharing CuO6 octahedra. There are four shorter (1.96 Å) and two longer (2.61 Å) Cu–O bond lengths. As+3.50+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is one shorter (1.81 Å) and two longer (1.85 Å) As–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu1+ and two equivalent As+3.50+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cu1+ and one As+3.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(RhO2)2 by Materials Project

CuRh2O4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Rh+3.50+ is bonded to six equivalent O2- atoms to form RhO6 octahedra that share corners with six equivalent CuO4 tetrahedra and edges with six equivalent RhO6 octahedra. All Rh–O bond lengths are 2.07 Å. Cu1+ is bonded to four equivalent O2- atoms to form CuO4 tetrahedra that share corners with twelve equivalent RhO6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Cu–O bond lengths are 2.03 Å. O2- is bonded to three equivalent Rh+3.50+ and one Cu1+ atom to form a mixture of distorted corner and edge-sharing OCuRh3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(BiO2)2 by Materials Project

CuBi2O4 crystallizes in the tetragonal P4/ncc space group. The structure is three-dimensional. Cu2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.96 Å. Bi3+ is bonded to six equivalent O2- atoms to form a mixture of distorted corner and edge-sharing BiO6 pentagonal pyramids. There are a spread of Bi–O bond distances ranging from 2.21–2.69 Å. O2- is bonded in a 4-coordinate geometry to one Cu2+ and three equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(BiO2)2 by Materials Project

CuBi2O4 crystallizes in the tetragonal I4cm space group. The structure is three-dimensional. Cu2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.95 Å. Bi3+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. There are a spread of Bi–O bond distances ranging from 2.25–2.91 Å. O2- is bonded in a 3-coordinate geometry to one Cu2+ and three equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(SbO3)2 by Materials Project

CuSb2O6 is Hydrophilite-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with eight equivalent SbO6 octahedra and edges with two equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 51–52°. There are two shorter (2.07 Å) and four longer (2.08 Å) Cu–O bond lengths. Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four equivalent CuO6 octahedra, corners with four equivalent SbO6 octahedra, an edgeedge with one CuO6 octahedra, and an edgeedge with one SbO6 octahedra. The corner-sharing octahedra tilt angles range from 48–52°. There are two shorter (2.01 Å) and four longer (2.03 Å) Sb–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Cu2+ and two equivalent Sb5+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two equivalent Sb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(SbO2)2 by Materials Project

CuSb2O4 crystallizes in the tetragonal P4_2/mbc space group. The structure is three-dimensional. Cu2+ is bonded to six O2- atoms to form edge-sharing CuO6 octahedra. There are four shorter (1.99 Å) and two longer (2.48 Å) Cu–O bond lengths. Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is one shorter (1.98 Å) and two longer (2.00 Å) Sb–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cu2+ and one Sb3+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to one Cu2+ and two equivalent Sb3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(NF2)2 by Materials Project

CuF4N2 crystallizes in the orthorhombic Cmce space group. The structure is two-dimensional and consists of eight ammonia molecules and two CuF4 sheets oriented in the (0, 1, 0) direction. In each CuF4 sheet, Cu2+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Cu–F bond distances ranging from 1.80–2.24 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to two equivalent Cu2+ atoms. In the second F1- site, F1- is bonded in a single-bond geometry to one Cu2+ atom.

36 MATERIALS SCIENCE↗