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8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on NaTm(SO4)2 by Materials Project

NaTm(SO4)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.84 Å. Tm3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Tm–O bond distances ranging from 2.24–2.34 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. In the second S6+ site, S6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.46–1.50 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Tm3+, and one S6+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Tm3+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Tm3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Tm3+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Tm3+, and one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaTm by Materials Project

NaTm is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Na is bonded to six equivalent Na and six equivalent Tm atoms to form NaNa6Tm6 cuboctahedra that share corners with eighteen equivalent NaNa6Tm6 cuboctahedra, edges with six equivalent NaNa6Tm6 cuboctahedra, edges with twelve equivalent TmNa6Tm6 cuboctahedra, faces with eight equivalent NaNa6Tm6 cuboctahedra, and faces with twelve equivalent TmNa6Tm6 cuboctahedra. All Na–Na bond lengths are 3.43 Å. All Na–Tm bond lengths are 3.69 Å. Tm is bonded to six equivalent Na and six equivalent Tm atoms to form TmNa6Tm6 cuboctahedra that share corners with eighteen equivalent TmNa6Tm6 cuboctahedra, edges with six equivalent TmNa6Tm6 cuboctahedra, edges with twelve equivalent NaNa6Tm6 cuboctahedra, faces with eight equivalent TmNa6Tm6 cuboctahedra, and faces with twelve equivalent NaNa6Tm6 cuboctahedra. All Tm–Tm bond lengths are 3.43 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaTm(Pd3O4)2 by Materials Project

NaTm(Pd3O4)2 crystallizes in the cubic Pm-3 space group. The structure is three-dimensional. Na1+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Na–O bond lengths are 2.63 Å. Tm3+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Tm–O bond lengths are 2.40 Å. Pd2+ is bonded in a square co-planar geometry to four O2- atoms. All Pd–O bond lengths are 2.06 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+, one Tm3+, and three equivalent Pd2+ atoms to form a mixture of corner and edge-sharing ONaTmPd3 trigonal bipyramids. In the second O2- site, O2- is bonded to one Na1+, one Tm3+, and three equivalent Pd2+ atoms to form a mixture of corner and edge-sharing ONaTmPd3 trigonal bipyramids. All O–Pd bond lengths are 2.06 Å. In the third O2- site, O2- is bonded to one Na1+, one Tm3+, and three equivalent Pd2+ atoms to form a mixture of corner and edge-sharing ONaTmPd3 trigonal bipyramids. In the fourth O2- site, O2- is bonded to one Na1+, one Tm3+, and three equivalent Pd2+ atoms to form a mixture of corner and edge-sharing ONaTmPd3 trigonal bipyramids. In the fifth O2- site, O2- is bonded to one Na1+, one Tm3+, and three equivalent Pd2+ atoms to form a mixture of corner and edge-sharing ONaTmPd3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Scalable synthesis of nanoporous atomically thin graphene membranes for dialysis and molecular separations via facile isopropanol-assisted hot lamination

Scalable graphene synthesis and facile large-area membrane fabrication are imperative to advance nanoporous atomically thin membranes (NATMs) for molecular separations. Although chemical vapor deposition (CVD) allows for roll-to-roll high-quality monolayer graphene synthesis, facile transfer with atomically clean interfaces to porous supports for large-area NATM fabrication remains extremely challenging. Sacrificial polymer scaffolds commonly used for graphene transfer typically leave polymer residues detrimental to membrane performance and transfers without polymer scaffolds suffer from low yield resulting in high non-selective leakage through NATMs. In this study, we systematically study the factors influencing graphene NATM fabrication and report on a novel roll-to-roll manufacturing compatible isopropanol-assisted hot lamination (IHL) process that enables scalable, facile and clean transfer of CVD graphene on to polycarbonate track etched (PCTE) supports with coverage ≥99.2%, while preserving support integrity/porosity. We demonstrate fully functional centimeter-scale graphene NATMs that show record high permeances (~2–3 orders of magnitude higher) and better selectivity than commercially available state-of-the-art polymeric dialysis membranes, specifically in the 0–1000 Da range. Our work highlights a scalable approach to fabricate graphene NATMs for practical applications and is fully compatible with roll-to-roll manufacturing processes.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2021

A Cobalt– and Manganese–Free High–Nickel Layered Oxide Cathode for Long–Life, Safer Lithium–Ion Batteries

High-nickel LiNi 1–x–y Mn x Co y O 2 and LiNi 1–x–y Co x Al y O 2 cathodes are receiving growing attention due to the burgeoning demands on high-energy-density lithium-ion batteries. The presence of both cobalt and manganese in them, however, triggers multiple issues, including high cost, high toxicity, rapid surface deterioration, and severe transition-metal dissolution. Herein, a Co- and Mn-free ultrahigh-nickel LiNi 0.93 Al 0.05 Ti 0.01 Mg 0.01 O 2 (NATM) cathode that exhibits 82% capacity retention over 800 deep cycles in full cells, outperforming two representative high-Ni cathodes LiNi 0.94 Co 0.06 O 2 (NC, 52%) and LiNi 0.90 Mn 0.05 Co 0.05 O 2 (NMC, 60%) is presented. It is demonstrated that a titanium-enriched surface along with aluminum and magnesium as the stabilizing ions in NATM not only ameliorates unwanted side reactions with the electrolyte and structural disintegrity, but also mitigates transition-metal dissolution and active lithium loss on the graphite anode. As a result, the graphite anode paired with NATM displays an ultrathin (≈8 nm), monolayer anode-electrolyte interphase architecture after extensive cycling. Furthermore, NATM displays considerably enhanced thermal stability with an elevated exothermic temperature (213 °C for NATM vs 180 and 190 °C for NC and NMC, respectively) and remarkably reduced heat release. This work sheds light on rational compositional design to adopt ultrahigh-Ni cathodes in lithium-based batteries with low cost, long service life, and improved thermal stability.

25 ENERGY STORAGE↗
DOE OSTI2025

Size-Selective Nanoporous Atomically Thin Graphene Separators for Lithium–Sulfur Batteries

Lithium–sulfur batteries (LSBs) are extensively researched for their high energy densities but are hindered by the lithium polysulfide (LiPS) shuttling effect, which results in poor cyclability. A popular mitigation strategy is separator modification, where a LiPS trapping material is slurry-coated onto a conventional microporous polypropylene (PP) separator. This additional mass and volume unfortunately compromise the overall energy density of the LSB. This study aims to take a separator modification approach that avoids this issue. Nanoporous atomically thin membranes (NATMs) made of graphene are gaining attention for their scalable synthesis, tunable pore size, and negligible pore length. Herein, we apply a well-characterized graphene NATM for reasons similar to those of a size-selective interlayer in LSBs. The tailored pore size of ∼0.7–1.0 nm and atomic thinness facilitate the passage of Li + (solvated ionic diameters ∼0.54–1.26 nm) and blockage of larger LiPS (solvated ionic diameters ∼0.81–1.69 nm) without adding significant impedances or mass. The sulfur confinement is confirmed through scanning electron microscopy and energy-dispersive X-ray spectroscopy elemental analysis of the Li anode. An LSB with a NATM@PP separator shows virtually no capacity loss over 150 cycles, demonstrating efficacy of size-selective molecular sieving using NATMs in LSBs.

battery separator↗
DOE OSTI2020

Facile Size-Selective Defect Sealing in Large-Area Atomically Thin Graphene Membranes for Sub-Nanometer Scale Separations

Atomically thin graphene with a high-density of precise subnanometer pores represents the ideal membrane for ionic and molecular separations. However, a single large-nanopore can severely compromise membrane performance and differential etching between pre-existing defects/grain boundaries in graphene and pristine regions presents fundamental limitations. Here, we show for the first time that size-selective interfacial polymerization after high-density nanopore formation in graphene not only seals larger defects (>0.5 nm) and macroscopic tears but also successfully preserves the smaller subnanometer pores. Low-temperature growth followed by mild UV/ozone oxidation allows for facile and scalable formation of high-density (4–5.5 $\times$ 10 12 cm –2 ) useful subnanometer pores in the graphene lattice. We demonstrate scalable synthesis of fully functional centimeter-scale nanoporous atomically thin membranes (NATMs) with water (~0.28 nm) permeance ~23$\times$ higher than commercially available membranes and excellent rejection to salt ions (~0.66 nm, >97% rejection) as well as small organic molecules (~0.7–1.5 nm, ~100% rejection) under forward osmosis. $\times$

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

Protein-Enabled Size-Selective Defect-Sealing of Atomically Thin 2D Membranes for Dialysis and Nanoscale Separations

Atomically thin 2D materials present the potential for advancing membrane separations via a combination of high selectivity (from molecular sieving) and high permeance (due to atomic thinness). However, the creation of a high density of precise nanopores (narrow-size-distribution) over large areas in 2D materials remains challenging, and nonselective leakage from nanopore heterogeneity adversely impacts performance. Here, we demonstrate protein-enabled size-selective defect sealing (PDS) for atomically thin graphene membranes over centimeter scale areas by leveraging the size and reactivity of permeating proteins to preferentially seal larger nanopores (≥4 nm) while preserving a significant amount of smaller nanopores (via steric hindrance). Our defect-sealed nanoporous atomically thin membranes (NATMs) show stability up to ~35 days during size-selective diffusive separations with a model dialysis biomolecule fluorescein isothiocyanate (FITC)-Ficoll 70 in phosphate buffer saline (PBS) solution as well as outperform state-of-the-art commercially available dialysis membranes (molecular-weight-cutoff ~3.5–5 kDa and ~8–10 kDa) with significantly higher permeance for smaller solutes KCl (~0.66 nm) ~5.1–6 × 10 –5 ms –1 and vitamin B12 (B12, ~1.5 nm) ~2.8–4 × 10 –6 ms –1 compared to small protein lysozyme (Lz, ~4 nm) ~4–6.4 × 10 –8 m s –1 , thereby allowing unprecedented selectivity for B12/Lz ~70 and KCl/Lz ~1280. Our work introduces proteins as nanoscale tools for size-selective defect sealing in atomically thin membranes to overcome persistent issues and advance separations for dialysis, protein desalting, small molecule separations/purification, and other bioprocesses.

77 NANOSCIENCE AND NANOTECHNOLOGY↗