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At least 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on NdH5(SeO4)2 by Materials Project

NdH3Se2O7H2O crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional and consists of four water molecules and one NdH3Se2O7 framework. In the NdH3Se2O7 framework, Nd3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Nd–O bond distances ranging from 2.35–2.57 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.75 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are two inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.70 Å) and two longer (1.75 Å) Se–O bond length. In the second Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.81 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Nd3+ and one Se4+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Nd3+ and one Se4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Nd3+ and one Se4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nd3+, one H1+, and one Se4+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Nd3+ and one Se4+ atom. In the sixth O2- site, O2- is bonded in a water-like geometry to one H1+ and one Se4+ atom. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to one Nd3+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2H18Se2O17 by Materials Project

(MgH8SeO8)2H2O crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of four water molecules and one MgH8SeO8 framework. In the MgH8SeO8 framework, there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two SeO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.15 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two SeO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.13 Å. There are sixteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.68 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.69 Å) H–O bond length. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (0.99 Å) and one longer (1.73 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.69 Å) H–O bond length. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are two inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with two MgO6 octahedra. The corner-sharing octahedra tilt angles range from 38–53°. There are a spread of Se–O bond distances ranging from 1.67–1.69 Å. In the second Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with two MgO6 octahedra. The corner-sharing octahedra tilt angles range from 31–52°. There are a spread of Se–O bond distances ranging from 1.66–1.69 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one Se6+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two H1+ and one Se6+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one Se6+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one Se6+ atom. In the tenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one Se6+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to one Se6+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two H1+ and one Se6+ atom. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one Se6+ atom. In the fifteenth O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and two H1+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn6P4H14O23 by Materials Project

Zn6P4H10O21(H2O)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of four water molecules and one Zn6P4H10O21 framework. In the Zn6P4H10O21 framework, there are six inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share a cornercorner with one ZnO6 octahedra, corners with four PO4 tetrahedra, and edges with two ZnO6 octahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Zn–O bond distances ranging from 2.04–2.36 Å. In the second Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with four PO4 tetrahedra, a cornercorner with one ZnO5 trigonal bipyramid, and edges with two ZnO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.04–2.21 Å. In the third Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share a cornercorner with one ZnO6 octahedra, a cornercorner with one ZnO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one ZnO6 octahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Zn–O bond distances ranging from 2.06–2.19 Å. In the fourth Zn2+ site, Zn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Zn–O bond distances ranging from 2.01–2.56 Å. In the fifth Zn2+ site, Zn2+ is bonded to four O2- atoms to form distorted ZnO4 tetrahedra that share a cornercorner with one ZnO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one ZnO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 75°. There are a spread of Zn–O bond distances ranging from 1.96–2.02 Å. In the sixth Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share a cornercorner with one ZnO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 71°. There are a spread of Zn–O bond distances ranging from 1.98–2.22 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four ZnO6 octahedra and a cornercorner with one ZnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 45–58°. There is three shorter (1.56 Å) and one longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three ZnO6 octahedra, a cornercorner with one ZnO4 tetrahedra, and a cornercorner with one ZnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 41–57°. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three ZnO6 octahedra, corners with two equivalent ZnO4 tetrahedra, and a cornercorner with one ZnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 50–57°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent ZnO6 octahedra, a cornercorner with one ZnO4 tetrahedra, and a cornercorner with one ZnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 46–57°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are ten inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.04 Å) and one longer (1.55 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.64 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.70 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the seventh H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.03 Å) and one longer (1.57 Å) H–O bond length. In the eighth H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.64 Å) H–O bond length. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are twenty-one inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Zn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a trigonal non-coplanar geometry to one P5+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Zn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Zn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Zn2+, one P5+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a water-like geometry to one Zn2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Zn2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two Zn2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one P5+ and two H1+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Zn2+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Zn2+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Zn2+ and two H1+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted water-like geometry to two Zn2+ and two H1+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted water-like geometry to two Zn2+ and two H1+ atoms. In the twentieth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Zn2+ and two H1+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted water-like geometry to one Zn2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Improving Rare-Earth Mineral Separation with Insights from Molecular Recognition: Functionalized Hydroxamic Acid Adsorption onto Bastnäsite and Calcite

Enhancing the separation of rare-earth elements (REEs) from gangue materials in mined ores requires an understanding of the fundamental interactions driving the adsorption of collector ligands onto mineral interfaces. In this work, we examine five functionalized hydroxamic acid ligands as potential collectors for the REE-containing bastnäsite mineral in froth flotation using density functional theory calculations and a suite of surface-sensitive analytical spectroscopies. These include vibrational sum frequency generation, attenuated total reflectance Fourier transform infrared, Raman, and X-ray photoelectron spectroscopies. Differences in the chemical makeup of these ligands on well-defined bastnäsite and calcite surfaces allow for a systematic relationship connecting the structure to adsorption activity to be framed in the context of interfacial molecular recognition. Here we show how the intramolecular hydrogen bonding of adsorbed ligands requires the inclusion of explicit water solvent molecules to correctly map energetic and structural trends measured by experiments. We anticipate that the results and insights from this work will motivate and inform the design of improved flotation collectors for REE ores.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Water desalination through the dewpoint evaporative system

This paper presents the first numerical analysis of a novel Dew Point Desalination unit (DPD), which utilizes the phenomenon of the evaporative cooling process to minimize energy consumption. The proposed solution is based on a modular structure, which allows it to obtain any required water production capacity. The analyses for various operational parameters and various climatic conditions are based on the numerical simulations conducted using a validated mathematical model. The system performance was described with different factors, including specific energy consumption (SEC) and daily water production rate respected to 1 m^3*s^-1 of passing air stream (DWP). It is shown that the DPD system can operate in almost every climate zone, and the desalinated water production consumes less than 1.5 kWh*m^-3 of electric energy It is noted the best performance of the DPD system is achieved in the semi-arid, desert and subtropical climate zones. In these climate zones, the 2-stage DPD system allows the production of desalinated water with an electric energy consumption SEC lower than 0.5 kWh*m^-3. The additional benefit of the DPD system is its modularity. The presented DPD system stands as a module, that can be multiplied as needed to achieve the desired size of the desalination plant.

Desalination↗
DOE OSTI2020

Materials Data on H8N2O by Materials Project

NH2H2NH3OH crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four ammonia molecules, four hydrogen molecules, and four water nitrogen molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Influence of Air and Ethanol Dehydration on Structure, Behavior, and Function of Type I Collagen Scaffolds

Ethanol dehydration is a common step in both scaffold manufacturing and tissue processing, yet the influence of ethanol on collagen is not well understood. This study examined the effects of dehydration, via ethanol treatment and air drying, on collagen structure, behavior, mechanics, and rehydration capacity. Multiple material characterization methods were used including Fourier Transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy, thermogravimetric analysis, small/medium angle x‐ray scattering, volumetric swelling analysis, and tensile testing. Ethanol dehydration removed bulk water from scaffolds, making them stronger and stiffer, but also showed loss of molecular water. This molecular water appears to act as a collagen stabilizer, resulting in less thermally stable scaffolds. The loss of molecular water is also evident in the molecular d‐spacing. Secondary structure of scaffolds was also altered by ethanol, resulting in significantly enhanced rehydration capacity. Bulk water, both before and after rehydration, largely determined mechanical properties, which did not correlate with other structural measures such as FTIR. While rehydration largely returned collagen spacing to pre‐ethanol treated state, structural alterations seen in FTIR cannot be recovered. These results have implications for not only collagen scaffolds, but in many tissue engineering and processing applications.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2020

Understanding water management in platinum group metal-free electrodes using neutron imaging

Platinum group metal-free (PGM-free) catalysts are a low-cost alternative to expensive PGM catalysts for polymer electrolyte fuel cells. However, due to the low volumetric activity of PGM-free catalysts, the catalyst layer thickness of the PGM-free catalyst electrode is an order of magnitude higher than PGM based electrodes. The thick PGM-free electrodes suffer from increased transport resistance and poor water management, which ultimately limits the fuel cell performance. This manuscript presents the study of water management in the PGM-free electrodes to understand the transport limitations and improve fuel cell performance. Here, in-operando neutron imaging is performed to estimate the water content in different components across the fuel cell thickness. Water saturation in thick PGM electrodes, with similar catalyst layer thickness to PGM-free electrodes, is lower than in the PGM-free electrodes irrespective of the operating conditions, due to high water retention by PGM-free catalysts. Improvements in fuel cell performance are accomplished by enhancing water removal from the flooded PGM-free electrode in three ways: (i) enhanced water removal with a novel microporous layer with hydrophilic pathways incorporated through hydrophilic additives, (ii) water removal through anode via novel GDL in the anode, and (iii) lower water saturation in PGM-free electrode structures with increased catalyst porosity.

25 ENERGY STORAGE↗
DOE OSTI2023

Ion solvation as a predictor of lanthanide adsorption structures and energetics in alumina nanopores

Adsorption reactions at solid-water interfaces define elemental fate and transport and enable contaminant clean-up, water purification, and chemical separations. For nanoparticles and nanopores, nanoconfinement may lead to unexpected and hard-to-predict products and energetics of adsorption, compared to analogous unconfined surfaces. Here we use X-ray absorption fine structure spectroscopy and operando flow microcalorimetry to determine nanoconfinement effects on the energetics and local coordination environment of trivalent lanthanides adsorbed on Al 2 O 3 surfaces. We show that the nanoconfinement effects on adsorption become more pronounced as the hydration free energy, ΔG hydr , of a lanthanide decreases. Neodymium (Nd 3+ ) has the least exothermic ΔG hydr (-3336 kJ·mol -1 ) and forms mostly outer-sphere complexes on unconfined Al 2 O 3 surfaces but shifts to inner-sphere complexes within the 4 nm Al 2 O 3 pores. Lutetium (Lu 3+ ) has the most exothermic ΔG hydr (-3589 kJ·mol -1 ) and forms inner-sphere adsorption complexes regardless of whether Al 2 O 3 surfaces are nanoconfined. Importantly, the energetics of adsorption is exothermic in nanopores only, and becomes endothermic with increasing surface coverage. Changes to the energetics and products of adsorption in nanopores are ion-specific, even within chemically similar trivalent lanthanide series, and can be predicted by considering the hydration energies of adsorbing ions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Water-Pillared Sodium Vanadium Bronze Nanowires for Enhanced Rechargeable Magnesium Ion Storage

Owing to the advantages of high safety, low cost, high theoretical volumetric capacities, and environmental friendliness, magnesium-ion batteries (MIBs) have more feasibility for large-scale energy storage compared to lithium-ion batteries. However, lack of suitable cathode materials due to sluggish kinetics of magnesium ion is one of the biggest challenges. Herein, water-pillared sodium vanadium bronze nanowires (Na 2 V 6 O 16 ·1.63H 2 O) are reported as cathode material for MIBs, which display high performance in magnesium storage. The hydrated sodium ions provide excellent structural stability. The charge shielding effect of lattice water enables fast Mg 2+ diffusion. It exhibits high specific capacity of 175 mAh g -1 , long cycle life (450 cycles), and high coulombic efficiency (≈100%). At high current density of 200 mA g -1 , the capacity retention is up to 71% even after 450 cycles (compared to the highest capacity), demonstrating excellent long-term cycling performance. The nature of charge storage kinetics is explored. Furthermore, a highly reversible structure change during the electrochemical process is proved by comprehensive electrochemical analysis. The remarkable electrochemical performance makes Na 2 V 6 O 16 ·1.63H 2 O a promising cathode material for low-cost and safe MIBs.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Structure of an Atmospheric River over Australia and the Southern Ocean. Part I: Tropical and Midlatitude Water Vapor Fluxes

An atmospheric river (AR) impacting Australia-Tasmania and the Southern Ocean during the Austral summer on 28-29 January 2018 during the SOCRATES campaign is analyzed using both a modeling and observational approach. Gulfstream-V dropsonde measurements and GPM radar analyses were used in conjunction with Weather Research and Forecasting model simulations with water vapor tracers to investigate the relative contributions of tropical and mid-latitude moisture sources to the AR. Moisture associated with a monsoonal tropical depression became entrained into a mid-latitude frontal system that extended to 60°S over the Southern Ocean reaching the associated low pressure system 850 km off the east coast of Antarctica – effectively connecting the tropics and the polar region. Tropical moisture contributed to about 50% of the precipitable water within the AR. The tropical contribution to precipitation decreased with latitude, from > 70% over the Australian continent, to ~50% off the Australian coast, to less than 10% poleward of 60°S. Precipitation in the AR conformed to a seeder-feeder model, the seeder precipitation forming primarily from tropical sourced moisture above the altitude of the 0°C isotherm, and the feeder precipitation sourced from mid-latitude sourced moisture below the altitude of the 0°C isotherm. The integrated vapor transport (IVT) through the core of the AR reached above 500 kg m-1s-1 during 1200 UTC 28 January to 0600 UTC 29 January 29, 1.29 times the average amount of water carried by the world’s largest river, the Amazon. The high IVT strength might be attributed to the higher water vapor content associated with the warmer temperatures in Austral summer.

Rauber, Robert M.↗
DOE OSTI2025

Molecular Origin of Nanoscale Anion Ordering of LiTFSI Electrolytes Revealed through SAXS/WAXS and Molecular Dynamics Simulations

Recent developments in “water-in-salt” electrolytes have precipitated a renewed effort to study imide-based electrolytes. While previous small-/wide-angle X-ray scattering (SAXS/WAXS) studies have attributed the emergence of a low-Q peak in the SAXS profile of aqueous LiTFSI electrolytes to nanometer-scale anion clustering, a molecular-level understanding of the root of these clusters remains unclear. Here, in this study, we combined molecular dynamics simulations and SAXS/WAXS to study the solvation structures of LiTFSI in acetonitrile, methanol, and water. We concluded that hydrogen bonding in water and MeOH stabilizes anion clusters, while nonpolar methyl groups on methanol and acetonitrile interrupt the nanoscale ordering of TFSI anions. This causes LiTFSI in water and MeOH electrolytes to exhibit two low-Q SAXS profile peaks while LiTFSI in acetonitrile exhibits only a single peak below Q = 1 Å –1 . These findings shed light on the underlying molecular origins of nanoscale anion clusters, which may help in the design of the next generation of electrolyte chemistries.

Trojanowski, Lucas [Univ. of Michigan, Ann Arbor, ↗
DOE OSTI2020

Centimeter-Scale Pillared-Layer Metal–Organic Framework Thin Films Mediated by Hydroxy Double Salt Intermediates for CO 2 Sensor Applications

Fabrication of metal–organic framework (MOF) thin films over macroscopic surface areas is a subject of great interest for gas sensor application platforms such as optics and microelectronics. However, a direct synthesis of MOF films at ambient conditions, in particular pillared-layer MOF films due to their anisotropic structures, remains a significant challenge. Herein, we demonstrate for the first time a facile construction of dense and continuous pillared-layer MOF thin films on a centimeter scale via an aluminum-doped zinc oxide template and hydroxy double salt (HDS) intermediates at room temperature. A series of Cu(II)-based pillared MOFs with different 1,4-benzenedicarboxylic acid (bdc) ligands were explored for optimizing MOF film formation for CO 2 sensor applications. Nonpolar ligands with lower water solubility preferentially formed crystalline pillared MOF structures from HDS intermediates. A Cu 2 (ndc) 2 (dabco) (ndc = 1,4-naphthalene-bdc; dabco = 1,4-diazabicyclo[2.2.2]octane) MOF demonstrated the most dense and uniform film growth with micrometer thickness over one square centimeter area. This synthetic approach for growing Cu 2 (ndc) 2 (dabco) MOF thin films was successfully translated toward two sensing platforms: a quartz crystal microbalance and an optical fiber sensor. These Cu 2 (ndc) 2 (dabco) MOF-coated sensors displayed sensitivity toward CO 2 and response/recovery time on the scale of seconds, even at moderate humidity levels. Finally, this work provides a road map for producing continuous and anisotropic crystalline MOF thin films over a centimeter scale area on various substrates, which will greatly facilitate their utilization in MOF-based sensor devices, among other applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on KH9O5 by Materials Project

(K(H2O)3)2(H2O)2H2O2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four water molecules; four water molecules; and one K(H2O)3 sheet oriented in the (1, 0, 0) direction. In the K(H2O)3 sheet, K1+ is bonded in a 3-coordinate geometry to two H1+ and six O2- atoms. There are one shorter (2.79 Å) and one longer (2.81 Å) K–H bond lengths. There are a spread of K–O bond distances ranging from 2.73–3.03 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.00 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to two equivalent K1+ and two H1+ atoms. In the second O2- site, O2- is bonded in a water-like geometry to two equivalent K1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a water-like geometry to two equivalent K1+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaH9O5 by Materials Project

NaH7O4H2O crystallizes in the orthorhombic P2_12_12_1 space group. The structure is one-dimensional and consists of four water molecules and two NaH7O4 ribbons oriented in the (0, 1, 0) direction. In each NaH7O4 ribbon, Na1+ is bonded to six O2- atoms to form face-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.36–2.48 Å. There are seven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the sixth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.64 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaH9O5 by Materials Project

(Na(H2O)3)2H2O2(H2O)2 crystallizes in the monoclinic C2 space group. The structure is one-dimensional and consists of four water molecules; four water molecules; and two Na(H2O)3 ribbons oriented in the (0, 1, 0) direction. In each Na(H2O)3 ribbon, Na1+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing NaO5 trigonal bipyramids. There are a spread of Na–O bond distances ranging from 2.37–2.41 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KH5O3 by Materials Project

(K2H9O5)2H2O2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional and consists of four water molecules and one K2H9O5 framework. In the K2H9O5 framework, there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to two H1+ and eight O2- atoms. There are one shorter (2.95 Å) and one longer (2.96 Å) K–H bond lengths. There are a spread of K–O bond distances ranging from 2.87–3.10 Å. In the second K1+ site, K1+ is bonded in a 9-coordinate geometry to two H1+ and seven O2- atoms. There are one shorter (2.88 Å) and one longer (2.97 Å) K–H bond lengths. There are a spread of K–O bond distances ranging from 2.83–3.14 Å. There are nine inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to one K1+ and two O2- atoms. There is one shorter (1.01 Å) and one longer (1.63 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fifth H1+ site, H1+ is bonded in a distorted single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.01 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.02 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the eighth H1+ site, H1+ is bonded in a distorted single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.01 Å. In the ninth H1+ site, H1+ is bonded in a distorted single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.01 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to four K1+ and two equivalent H1+ atoms. In the second O2- site, O2- is bonded in a water-like geometry to three K1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two H1+ atoms. In the fourth O2- site, O2- is bonded in a water-like geometry to four K1+ and two equivalent H1+ atoms. In the fifth O2- site, O2- is bonded in a water-like geometry to four K1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a water-like geometry to four K1+ and two equivalent H1+ atoms. In the seventh O2- site, O2- is bonded in a water-like geometry to four K1+ and two equivalent H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na4Sn2H26Se6O13 by Materials Project

(Na2SnH12(SeO2)3)2H2O crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of two water molecules and one Na2SnH12(SeO2)3 framework. In the Na2SnH12(SeO2)3 framework, there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form edge-sharing NaO5 square pyramids. There are a spread of Na–O bond distances ranging from 2.40–2.48 Å. In the second Na1+ site, Na1+ is bonded to one Se2- and five O2- atoms to form distorted NaSeO5 square pyramids that share a cornercorner with one NaSeO5 square pyramid, a cornercorner with one SnSe4 tetrahedra, an edgeedge with one NaO6 octahedra, and an edgeedge with one NaO5 square pyramid. The Na–Se bond length is 3.22 Å. There are a spread of Na–O bond distances ranging from 2.37–2.50 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.41–2.51 Å. In the fourth Na1+ site, Na1+ is bonded to one Se2- and five O2- atoms to form distorted NaSeO5 square pyramids that share corners with two equivalent NaO6 octahedra, a cornercorner with one NaSeO5 square pyramid, a cornercorner with one SnSe4 tetrahedra, and an edgeedge with one NaSeO5 square pyramid. The corner-sharing octahedra tilt angles range from 51–59°. The Na–Se bond length is 3.23 Å. There are a spread of Na–O bond distances ranging from 2.42–2.54 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share a cornercorner with one NaSeO5 square pyramid and an edgeedge with one SnSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.51–2.64 Å. In the second Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share a cornercorner with one NaSeO5 square pyramid and an edgeedge with one SnSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.50–2.64 Å. There are twenty-four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the seventeenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the nineteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twentieth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in an L-shaped geometry to two equivalent Sn4+ atoms. In the second Se2- site, Se2- is bonded in a single-bond geometry to one Sn4+ atom. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to one Na1+ and one Sn4+ atom. In the fourth Se2- site, Se2- is bonded in an L-shaped geometry to two equivalent Sn4+ atoms. In the fifth Se2- site, Se2- is bonded in a single-bond geometry to one Sn4+ atom. In the sixth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Na1+ and one Sn4+ atom. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the ninth O2- site, O2- is bonded in a water-like geometry to one Na1+ and two H1+ atoms. In the tenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eleventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the twelfth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.

36 MATERIALS SCIENCE↗