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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

THD-C Sheet: A Novel Nonbenzenoid Carbon Allotrope with Tetra-, Hexa-, and Dodeca-Membered Rings

Here, we propose a novel two-dimensional carbon-based structure with tetra-, hexa-, and dodeca-membered rings, which we refer to by the abbreviated name, THD-C. The structure presents a mixture of sp–sp 2 hybridization and can potentially be synthesized by the topological assembly of 4-ethynyldiphenylacetylene molecules. By employing first-principles calculations, the stability and ease of synthesis of the sheet are investigated and compared with various C-allotropes. We predict its metallic behavior and excellent kinetic and dynamic stability. Due to the crystal structure of the sheet, a strong mechanical anisotropy is observed. The effects of functionalization on the electronic properties of the material are also studied, and different semiconducting systems are obtained. The potential of THD-C for energy storage in metal-based batteries, hydrogen storage, and catalysis is also investigated, and we find a superior performance in comparison to graphite and other allotropes. The quantum confinement effect is investigated by constructing nanoribbons and nanotubes of various sizes. For ribbons, we find that tailor-made electronic and magnetic properties can be obtained and explored in potential spintronic devices. Additionally, we observe that nanotubes are conducting irrespective of their chirality and can potentially be used for capture, storage, and separation of industrially relevant small gas molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Advanced nanoscale characterization of aluminum nanoparticles with modified surface morphology via atmospheric helium and carbon monoxide plasmas

Aluminum nanoparticles (nAl) have the potential as energetic additives in explosive/propellant formulations. Scalable methodologies must be pursued to mitigate the inactive amorphous alumina shell surrounding the active aluminum (Al) core with modified surface morphology and chemistry for increased combustion effects. This work explores the feasibility of making reactive core/shell nAl with thinned oxide shells and modified surface coatings via a two-step atmospheric plasma surface treatment process in a custom dielectric barrier discharge plasma reactor. The commercial nAl of nominal average size similar to 40-60nm was first treated with helium (He) followed by He/carbon monoxide (CO) plasmas for different durations. The resultant samples were characterized via high-resolution transmission electron microscopy (HRTEM) and Fourier transform IR (FTIR) spectra. HRTEM images revealed sporadic patchy gamma -alumina deposits on particle surfaces and in gaps among particles for all samples, suggesting the non-uniform plasma effects of the He/CO glow. Nanoscale chemical analyses via scanning transmission electron microscopy elemental mapping and x-ray energy dispersive spectroscopy were further performed. Although no carbon-associated structure appeared in electron energy loss spectroscopy (EELS) spectra, the presence of carbonaceous materials was confirmed as a thin dispersive layer evenly distributed on the nAl surface suggesting either its amorphous nature or is present at a level insufficient to generate satisfactory EELS spectra. The trend of intensity profiles for key elements acquired by drawing lines across a single particle on the elemental maps confirmed that carbonaceous materials only existed on the surface and they were most likely carboxylates that increased with increased He/CO treatment duration, as evident by FTIR results. Finally, this work demonstrated the success of atmospheric plasma-treated reactive nAl with comprehensively characterized surface features via advanced microscopy and spectroscopy.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Windthrow characteristics and their regional association with rainfall, soil, and surface elevation in the Amazon

Abstract Windthrows (trees uprooted and broken by winds) are common across the Amazon. They range in size from single trees to large gaps that lead to changes in forest dynamics, composition, structure, and carbon balance. Yet, the current understanding of the spatial variability of windthrows is limited. By integrating remote sensing data and geospatial analysis, we present the first study to examine the occurrence, area, and direction of windthrows and the control that environmental variables exert on them across the whole Amazon. Windthrows are more frequent and larger in the northwestern Amazon (Peru and Colombia), with the central Amazon (Brazil) being another hot spot of windthrows. The predominant direction of windthrows is westward. Rainfall, surface elevation, and soil characteristics explain the variability (20%–50%) of windthrows but their effects vary regionally. A better understanding of the spatial dynamics of windthrows will improve understanding of the functioning of Amazon forests.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Spatially structured bacterial interactions alter algal carbon flow to bacteria

Phytoplankton account for nearly half of global photosynthetic carbon fixation, and the fate of that carbon is regulated in large part by microbial food web processing. We currently lack a mechanistic understanding of how interactions among heterotrophic bacteria impact the fate of photosynthetically fixed carbon. Here, we used a set of bacterial isolates capable of growing on exudates from the diatom Phaeodactylum tricornutum to investigate how bacteria-bacteria interactions affect the balance between exudate remineralization and incorporation into biomass. With exometabolomics and genome-scale metabolic modeling, we estimated the degree of resource competition between bacterial pairs. In a sequential spent media experiment, we found that pairwise interactions were more beneficial than predicted based on resource competition alone, and 30% exhibited facilitative interactions. To link this to carbon fate, we used single-cell isotope tracing in a custom cultivation system to compare the impact of different "primary" bacterial strains in close proximity to live P. tricornutum on a distal "secondary" strain. We found that a primary strain with a high degree of competition decreased secondary strain carbon drawdown by 51% at the single-cell level, providing a quantitative metric for the "cost" of competition on algal carbon fate. Additionally, a primary strain classified as facilitative based on sequential interactions increased total algal-derived carbon assimilation by 7.6 times, integrated over all members, compared to the competitive primary strain. Our findings suggest that the degree of interaction between bacteria along a spectrum from competitive to facilitative is directly linked to algal carbon drawdown.

genome-scale metabolic model↗
DOE OSTI2020

Materials Data on CO by Materials Project

CO is alpha carbon monoxide structured and crystallizes in the cubic P2_13 space group. The structure is zero-dimensional and consists of four formaldehyde molecules. C2+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.14 Å. O2- is bonded in a single-bond geometry to one C2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HBr by Materials Project

HBr is alpha carbon monoxide structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules. H1+ is bonded in a single-bond geometry to one Br1- atom. The H–Br bond length is 1.44 Å. Br1- is bonded in a single-bond geometry to one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Se2NCl3 by Materials Project

N2(Se2Cl3)2 is alpha carbon monoxide structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four ammonia molecules and four Se2Cl3 clusters. In each Se2Cl3 cluster, there are two inequivalent Se1+ sites. In the first Se1+ site, Se1+ is bonded in a distorted linear geometry to two Cl1- atoms. There are one shorter (2.22 Å) and one longer (2.70 Å) Se–Cl bond lengths. In the second Se1+ site, Se1+ is bonded in a distorted linear geometry to two Cl1- atoms. There are one shorter (2.25 Å) and one longer (2.64 Å) Se–Cl bond lengths. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Se1+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Se1+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Se1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsN9 by Materials Project

AsN9 is Theoretical Carbon Structure-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four AsN9 clusters. As5+ is bonded in a distorted T-shaped geometry to three N+0.56- atoms. There are a spread of As–N bond distances ranging from 1.94–1.96 Å. There are nine inequivalent N+0.56- sites. In the first N+0.56- site, N+0.56- is bonded in a bent 120 degrees geometry to one As5+ and one N+0.56- atom. The N–N bond length is 1.23 Å. In the second N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. The N–N bond length is 1.15 Å. In the third N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms. The N–N bond length is 1.15 Å. In the fourth N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. The N–N bond length is 1.15 Å. In the fifth N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. In the sixth N+0.56- site, N+0.56- is bonded in a distorted bent 120 degrees geometry to one As5+ and one N+0.56- atom. The N–N bond length is 1.23 Å. In the seventh N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms. The N–N bond length is 1.23 Å. In the eighth N+0.56- site, N+0.56- is bonded in a distorted bent 120 degrees geometry to one As5+ and one N+0.56- atom. In the ninth N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H8C2S3(NO3)2 by Materials Project

C2H8S3(NO3)2 is Theoretical Carbon Structure-like structured and crystallizes in the monoclinic P2/c space group. The structure is zero-dimensional and consists of four ~{n}-(methylsulfonylsulfamoyl)methanesulfonamide molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2AlCoO4 by Materials Project

Li2CoAlO4 is Theoretical Carbon Structure-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent CoO4 tetrahedra, corners with four equivalent LiO4 tetrahedra, corners with four equivalent AlO4 tetrahedra, and an edgeedge with one CoO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.96–2.13 Å. Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with four equivalent LiO4 tetrahedra, corners with four equivalent AlO4 tetrahedra, and edges with two equivalent LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.86–1.90 Å. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four equivalent CoO4 tetrahedra and corners with eight equivalent LiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.79 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLi2AlCo tetrahedra. In the second O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form corner-sharing OLi2AlCo tetrahedra. In the third O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form a mixture of edge and corner-sharing OLi2AlCo trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si by Materials Project

Si is Theoretical Carbon Structure-like structured and crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are four inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.35–2.42 Å. In the second Si site, Si is bonded to four equivalent Si atoms to form distorted corner-sharing SiSi4 tetrahedra. In the third Si site, Si is bonded to four equivalent Si atoms to form corner-sharing SiSi4 tetrahedra. All Si–Si bond lengths are 2.37 Å. In the fourth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2MgGeO4 by Materials Project

Li2MgGeO4 is Theoretical Carbon Structure-derived structured and crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with two equivalent MgO4 tetrahedra, corners with four equivalent GeO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one MgO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.07 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with four equivalent MgO4 tetrahedra, corners with four equivalent GeO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.98–2.04 Å. Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with four equivalent GeO4 tetrahedra, corners with six LiO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.96–2.01 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four equivalent MgO4 tetrahedra and corners with eight LiO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.77–1.79 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Li1+, one Mg2+, and one Ge4+ atom to form corner-sharing OLi2MgGe tetrahedra. In the second O2- site, O2- is bonded to two Li1+, one Mg2+, and one Ge4+ atom to form a mixture of corner and edge-sharing OLi2MgGe tetrahedra. In the third O2- site, O2- is bonded to two Li1+, one Mg2+, and one Ge4+ atom to form a mixture of corner and edge-sharing OLi2MgGe tetrahedra. In the fourth O2- site, O2- is bonded to two Li1+, one Mg2+, and one Ge4+ atom to form a mixture of corner and edge-sharing OLi2MgGe trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IrWN5ClO4 by Materials Project

WIrN5O4Cl is Theoretical Carbon Structure-like structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four WIrN5O4Cl clusters. W6+ is bonded in a 5-coordinate geometry to four O2- and one Cl1- atom. There are two shorter (1.75 Å) and two longer (2.38 Å) W–O bond lengths. The W–Cl bond length is 2.54 Å. Ir4+ is bonded in a distorted trigonal non-coplanar geometry to three N+0.20- and one Cl1- atom. There is two shorter (1.75 Å) and one longer (1.76 Å) Ir–N bond length. The Ir–Cl bond length is 2.53 Å. There are three inequivalent N+0.20- sites. In the first N+0.20- site, N+0.20- is bonded in a single-bond geometry to one Ir4+ atom. In the second N+0.20- site, N+0.20- is bonded in a single-bond geometry to one O2- atom. The N–O bond length is 1.19 Å. In the third N+0.20- site, N+0.20- is bonded in a distorted single-bond geometry to one Ir4+ atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one W6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one W6+ and one N+0.20- atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one W6+ atom. Cl1- is bonded in a bent 120 degrees geometry to one W6+ and one Ir4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li3PS4 by Materials Project

Li3PS4 is Theoretical Carbon Structure-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share corners with four equivalent LiS4 tetrahedra, corners with four equivalent PS4 tetrahedra, corners with two equivalent LiS4 trigonal pyramids, and an edgeedge with one LiS4 trigonal pyramid. There are a spread of Li–S bond distances ranging from 2.38–2.50 Å. In the second Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 trigonal pyramids that share corners with four equivalent LiS4 tetrahedra, corners with four equivalent PS4 tetrahedra, and edges with two equivalent LiS4 tetrahedra. There are a spread of Li–S bond distances ranging from 2.41–2.60 Å. P5+ is bonded to four S2- atoms to form PS4 tetrahedra that share corners with eight equivalent LiS4 tetrahedra and corners with four equivalent LiS4 trigonal pyramids. There are a spread of P–S bond distances ranging from 2.05–2.07 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to three Li1+ and one P5+ atom to form corner-sharing SLi3P tetrahedra. In the second S2- site, S2- is bonded to three Li1+ and one P5+ atom to form a mixture of edge and corner-sharing SLi3P tetrahedra. In the third S2- site, S2- is bonded to three Li1+ and one P5+ atom to form a mixture of edge and corner-sharing SLi3P trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C by Materials Project

C is Theoretical Carbon Structure-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent C sites. In the first C site, C is bonded to four C atoms to form corner-sharing CC4 tetrahedra. There is two shorter (1.54 Å) and two longer (1.57 Å) C–C bond length. In the second C site, C is bonded to four C atoms to form corner-sharing CC4 tetrahedra. There is one shorter (1.56 Å) and one longer (1.63 Å) C–C bond length. In the third C site, C is bonded to four C atoms to form corner-sharing CC4 tetrahedra. There is one shorter (1.50 Å) and two longer (1.53 Å) C–C bond length. In the fourth C site, C is bonded to four C atoms to form corner-sharing CC4 tetrahedra. Both C–C bond lengths are 1.52 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si by Materials Project

Si is Theoretical Carbon Structure-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.35–2.39 Å. In the second Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.40 Å) and one longer (2.42 Å) Si–Si bond lengths. In the third Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.32 Å) and two longer (2.35 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. Both Si–Si bond lengths are 2.35 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si by Materials Project

Si is Theoretical Carbon Structure-like structured and crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are four inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. There are one shorter (2.34 Å) and three longer (2.38 Å) Si–Si bond lengths. In the second Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.35 Å) and three longer (2.39 Å) Si–Si bond lengths. In the third Si site, Si is bonded to four equivalent Si atoms to form corner-sharing SiSi4 tetrahedra. In the fourth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li3AsO4 by Materials Project

Li3AsO4 is Theoretical Carbon Structure-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four equivalent AsO4 tetrahedra, corners with six LiO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.04 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four equivalent LiO4 tetrahedra, corners with four equivalent AsO4 tetrahedra, and edges with two equivalent LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.98–2.04 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with twelve LiO4 tetrahedra. There is three shorter (1.72 Å) and one longer (1.73 Å) As–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and one As5+ atom to form a mixture of edge and corner-sharing OLi3As trigonal pyramids. In the second O2- site, O2- is bonded to three Li1+ and one As5+ atom to form a mixture of edge and corner-sharing OLi3As tetrahedra. In the third O2- site, O2- is bonded to three Li1+ and one As5+ atom to form corner-sharing OLi3As tetrahedra.

36 MATERIALS SCIENCE↗