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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Total metal, carbon, anion, iron speciation, and sulfide concentrations; Slate River, East River, and Trail Creek surface water and floodplains, Crested Butte, CO; May 2023–August 2023

This data package comprises analytical results and metadata from stream and groundwater samples collected from the Slate River, East River, Trail Creek, and their respective floodplains. This dataset contains five files: (1) a samples file (2023_SFA_Field_samples.csv) that contains site information; (2) a chemical analysis data file (2023_FieldWaterSampleData_IC__ICPOES__ICPMS__TOC__Fe__S_chem_data.csv) that contains sample analysis values; (3) a file-level metadata file (flmd.csv) that lists each file contained in the dataset with associated metadata; (4) a data dictionary file (dd.csv) that contains column/row headers used throughout the files along with definitions, units, and data types; and (5) a methods file (methods.csv) that contains ID, type, description, instrument, and lab information for each method.The samples’ anion concentrations were measured using ion chromatography (IC), total metal concentrations using inductively coupled plasma emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS), non-purgeable organic carbon using total organic carbon (TOC) analysis, dissolved sulfide concentration using methylene blue spectrophotometry, and iron speciation using the ferrozine assay. To support bulk chemical analyses and colloid characterization, samples were collected from multiple depths ranging from the surface to 3.5 meters below ground.Update on 2024-10-18: Updates were made to the 2023_FieldWaterSampleData_IC__ICPOES__ICPMS__TOC__Fe__S_chem_data.csv and dd.csv files to correct units (ppb instead of ppm).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

On the length scale and rate-dependent mechanical behavior of monolithic (oxy)sulfidic glassy solid-state electrolytes

In the controlled atmosphere of a dedicated glove box, nanoindentation performed with a diamond Berkovich indenter tip has been used to examine the mechanical behavior of three (oxy)sulfide solid-state electrolytes (SSEs), 70Li 2 S·(30–x)P 2 S 5 ·xP 2 O 5 (x = 0, 2, and 5). At a drive frequency of 120 Hz, the elastic modulus is found to be predominantly depth independent over the range of 100 nm to 1 μm and generally insensitive to the varying mol fraction of oxygen (0, 2, and 5%) as well as the imposed strain rates of 0.025, 0.05, and 0.1 1/s. All three SSEs exhibit significant room-temperature creep. Strain burst activity observed during loading (potentially representative of pore collapse or cracking) is attenuated with the addition of oxygen. The hardness is found to be insensitive to the imposed strain rates but varying with depth and oxygen content. Furthermore, the highest oxygen concentration yields the lowest hardness and strongest depth dependence.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Lithium nitride coatings deposited by magnetron sputtering on sulfide electrolytes for solid-state batteries

Lithium nitrides have been considered as promising candidates for interfacial layers in solid-state lithium batteries (SSBs). Previously reported lithium nitride (Li 3 N) coatings were mostly prepared by the reaction between lithium metal and nitrogen gas, which makes it challenging for their thickness control and integration in SSBs. In this study, we prepare Li 3 N via magnetron sputtering for the first time, and apply the resulting coating directly on sulfide solid-state electrolyte. A much smaller impedance increase associated with improved cycling performance is observed in lithium metal symmetric cell. These results demonstrate the feasibility of depositing Li 3 N via magnetron sputtering and its application in SSBs.

25 ENERGY STORAGE↗
DOE OSTI2023

Navigating the complexities of solvent and binder selection for solution processing of sulfide solid-state electrolytes

We introduce a paradigm of solvent and binder selection for solution-processing Li 6 PS 5 Cl solid-state electrolyte particles based on Hansen solubility parameters. Treatment of the Li 6 PS 5 Cl in selected solvents results in particle morphological change, but crystallographic structure remains intact. Although solution processing reduced the Li 6 PS 5 Cl ionic conductivity, it promotes interfacial stability by alleviating reduction of the solid electrolyte in contact with Li metal. In conclusion, these findings have the potential to enhance the stability, structural integrity, and performance of sulfide solid-state electrolytes in practical applications.

25 ENERGY STORAGE↗
DOE OSTI2021

Mitigation of Acute Hydrogen Sulfide and Ammonia Emissions from Swine Manure during Three-Hour Agitation Using Pelletized Biochar

The risk of inhalation exposure to elevated concentrations of hydrogen sulfide (H2S) and ammonia (NH3) during the agitation of stored swine manure is high. Once or twice a year, farmers agitate manure before pump-out and application to fields. Agitation of the swine manure causes the short-term releases of highly toxic levels of H2S and NH3. In our previous pilot-scale studies, the biochar powder showed significant mitigation of H2S and NH3 emissions when it was surficially applied to manure immediately before agitation. However, fine biochar powder application poses hazards by itself and may not be practical to apply on a farm scale, especially when livestock and workers are present. We hypothesized that applying pelletized biochar to manure surfaces is just as effective as applying powder to protect farmers and animals from excessive exposure to H2S and NH3. This work reports on the lab-scale proof-of-the-concept trials with biochar pellets on the lab scale. The objective was to compare the biochar pellets and biochar powder on their effectiveness of mitigation on H2S and NH3 gases during 3-h-long swine manure agitation. Three scenarios were compared in (n = 3) trials: (i) control, (ii) 12.5 mm thick surficial application to manure surface of biochar powder, and (iii) an equivalent (by mass) dose of pelletized biochar applied to the manure surface. The biochar powder was bound with 35% (wt) water into ~5 × 10 mm (dia × length) pellets. The biochar powder was significantly (p < 0.05) more effective than the biochar pellets. Still, pellets reduced total H2S and NH3 emissions by ~72% and ~68%, respectively (p = 0.001), compared with ~99% by powder (p = 0.001). The maximum H2S and NH3 concentrations were reduced from 48.1 ± 4.8 ppm and 1810 ± 850 ppm to 20.8 ± 2.95 ppm and 775 ± 182 ppm by pellets, and to 22.1 ± 16.9 ppm and 40.3 ± 57 ppm by powder, respectively. These reductions are equivalent to reducing the maximum concentrations of H2S and NH3 during the 3-h manure agitation by 57% and 57% (pellets) and 54% and 98% (powder), respectively. Treated manure properties hinted at improved nitrogen retention, yet they were not significant due to high variability. We recommend scaling up and trials on the farm-scale level using biochar pellets to assess the feasibility of application to large manure surfaces and techno-economic evaluation.

Chen, Baitong (ORCID:0000000266071253)↗
DOE OSTI2021

Ground State Properties of the Wide Band Gap Semiconductor Beryllium Sulfide (BeS)

We report the results from self-consistent calculations of electronic, transport, and bulk properties of beryllium sulfide (BeS) in the zinc-blende phase, and employed an ab-initio local density approximation (LDA) potential and the linear combination of atomic orbitals (LCAO). We obtained the ground state properties of zb-BeS with the Bagayoko, Zhao, and Williams (BZW) computational method, as enhanced by Ekuma and Franklin (BZW-EF). Our findings include the electronic energy bands, the total (DOS) and partial (pDOS) densities of states, electron and hole effective masses, the equilibrium lattice constant, and the bulk modulus. The calculated band structure clearly shows that zb-BeS has an indirect energy band gap of 5.436 eV, from Γ to a point between Γ and X, for an experimental lattice constant of 4.863 Å. This is in excellent agreement with the experiment, unlike the findings of more than 15 previous density functional theory (DFT) calculations that did not perform the generalized minimization of the energy functional, required by the second DFT theorem, which is inherent to the implementation of our BZW-EF method.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Exploring dimethyl sulfide (DMS) oxidation and implications for global aerosol radiative forcing

Abstract. Aerosol indirect radiative forcing (IRF), which characterizes how aerosols alter cloud formation and properties, is very sensitive to the preindustrial (PI) aerosol burden. Dimethyl sulfide (DMS), emitted from the ocean, is a dominant natural precursor of non-sea-salt sulfate in the PI and pristine present-day (PD) atmospheres. Here we revisit the atmospheric oxidation chemistry of DMS, particularly under pristine conditions, and its impact on aerosol IRF. Based on previous laboratory studies, we expand the simplified DMS oxidation scheme used in the Community Atmospheric Model version 6 with chemistry (CAM6-chem) to capture the OH-addition pathway and the H-abstraction pathway and the associated isomerization branch. These additional oxidation channels of DMS produce several stable intermediate compounds, e.g., methanesulfonic acid (MSA) and hydroperoxymethyl thioformate (HPMTF), delay the formation of sulfate, and, hence, alter the spatial distribution of sulfate aerosol and radiative impacts. The expanded scheme improves the agreement between modeled and observed concentrations of DMS, MSA, HPMTF, and sulfate over most marine regions, based on the NASA Atmospheric Tomography (ATom), the Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE-ENA), and the Variability of the American Monsoon Systems (VAMOS) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) measurements. We find that the global HPMTF burden and the burden of sulfate produced from DMS oxidation are relatively insensitive to the assumed isomerization rate, but the burden of HPMTF is very sensitive to a potential additional cloud loss. We find that global sulfate burden under PI and PD emissions increase to 412 Gg S (+29 %) and 582 Gg S (+8.8 %), respectively, compared to the standard simplified DMS oxidation scheme. The resulting annual mean global PD direct radiative effect of DMS-derived sulfate alone is −0.11 W m−2. The enhanced PI sulfate produced via the gas-phase chemistry updates alone dampens the aerosol IRF as anticipated (−2.2 W m−2 in standard versus −1.7 W m−2, with updated gas-phase chemistry). However, high clouds in the tropics and low clouds in the Southern Ocean appear particularly sensitive to the additional aqueous-phase pathways, counteracting this change (−2.3 W m−2). This study confirms the sensitivity of aerosol IRF to the PI aerosol loading and the need to better understand the processes controlling aerosol formation in the PI atmosphere and the cloud response to these changes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Product distribution, kinetics, and aerosol formation from the OH oxidation of dimethyl sulfide under different RO 2 regimes

Abstract. The atmospheric oxidation of dimethyl sulfide (DMS) represents a major natural source of atmospheric sulfate aerosols. However, there remain large uncertainties in our understanding of the underlying chemistry that governs the product distribution and sulfate yield from DMS oxidation. Here, chamber experiments were conducted to simulate gas-phase OH-initiated oxidation of DMS under a range of reaction conditions. Most importantly, the bimolecular lifetime (τbi) of the peroxy radical CH3SCH2OO was varied over several orders of magnitude, enabling the examination of the role of peroxy radical isomerization reactions on product formation. An array of analytical instruments was used to measure nearly all sulfur-containing species in the reaction mixture, and results were compared with a near-explicit chemical mechanism. When relative humidity was low, “sulfur closure” was achieved under both high-NO (τbi<0.1 s) and low-NO (τbi>10 s) conditions, though product distributions were substantially different in the two cases. Under high-NO conditions, approximately half the product sulfur was in the particle phase, as methane sulfonic acid (MSA) and sulfate, with most of the remainder as SO2 (which in the atmosphere would eventually oxidize to sulfate or be lost to deposition). Under low-NO conditions, hydroperoxymethyl thioformate (HPMTF, HOOCH2SCHO), formed from CH3SCH2OO isomerization, dominates the sulfur budget over the course of the experiment, suppressing or delaying the formation of SO2 and particulate matter. The isomerization rate constant of CH3SCH2OO at 295 K is found to be 0.13±0.03 s−1, in broad agreement with other recent laboratory measurements. The rate constants for the OH oxidation of key first-generation oxidation products (HPMTF and methyl thioformate, MTF) were also determined (kOH+HPMTF=2.1×10-11 cm3 molec.−1 s−1, kOH+MTF=1.35×10-11 cm3 molec.−1 s−1). Product measurements agree reasonably well with mechanistic predictions in terms of total sulfur distribution and concentrations of most individual species, though the mechanism overpredicts sulfate and underpredicts MSA under high-NO conditions. Lastly, results from high-relative-humidity conditions suggest efficient heterogenous loss of at least some gas-phase products.

Ye, Qing (ORCID:0000000337978988)↗
DOE OSTI2022

An approach to sulfate geoengineering with surface emissions of carbonyl sulfide

Sulfate geoengineering (SG) methods based on lower stratospheric tropical injection of sulfur dioxide (SO 2 ) have been widely discussed in recent years, focusing on the direct and indirect effects they would have on the climate system. Here a potential alternative method is discussed, where sulfur emissions are located at the surface or in the troposphere in the form of carbonyl sulfide (COS) gas. There are two time-dependent chemistry–climate model experiments designed from the years 2021 to 2055, assuming a 40 Tg-Syr -1 artificial global flux of COS, which is geographically distributed following the present-day anthropogenic COS surface emissions (SG-COS-SRF) or a 6 Tg-Syr -1 injection of COS in the tropical upper troposphere (SG-COS-TTL). The budget of COS and sulfur species is discussed, as are the effects of both SG-COS strategies on the stratospheric sulfate aerosol optical depth (~Δτ=0.080 in the years 2046–2055), aerosol effective radius (0.46 µm), surface SO x deposition (+8.9 % for SG-COS-SRF; +3.3 % for SG-COS-TTL), and tropopause radiative forcing (RF; ~-1.5 W m –2 in all-sky conditions in both SG-COS experiments). Indirect effects on ozone, methane and stratospheric water vapour are also considered, along with the COS direct contribution. According to our model results, the resulting net RF is –1.3 W m –2 , for SG-COS-SRF, and –1.5 W m –2 , for SG-COS-TTL, and it is comparable to the corresponding RF of –1.7 W m –2 obtained with a sustained injection of 4 Tg-Syr -1 in the tropical lower stratosphere in the form of SO 2 (SG-SO2, which is able to produce a comparable increase of the sulfate aerosol optical depth). Significant changes in the stratospheric ozone response are found in both SG-COS experiments with respect to SG-SO2 (~5 DU versus +1.4 DU globally). According to the model results, the resulting ultraviolet B (UVB) perturbation at the surface accounts for –4.3 % as a global and annual average (versus –2.4 % in the SG-SO2 case), with a springtime Antarctic decrease of –2.7 % (versus a +5.8 % increase in the SG-SO2 experiment). Overall, we find that an increase in COS emissions may be feasible and produce a more latitudinally uniform forcing without the need for the deployment of stratospheric aircraft. However, our assumption that the rate of COS uptake by soils and plants does not vary with increasing COS concentrations will need to be investigated in future work, and more studies are needed on the prolonged exposure effects to higher COS values in humans and ecosystems.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Chamber studies of OH + dimethyl sulfoxide and dimethyl disulfide: insights into the dimethyl sulfide oxidation mechanism

Abstract. The oxidation of dimethyl sulfide (DMS) in the marine atmosphere represents an important natural source of non-sea-salt sulfate aerosol, but the chemical mechanisms underlying this process remain uncertain. While recent studies have focused on the role of the peroxy radical isomerization channel in DMS oxidation, this work revisits the impact of the other channels (OH addition and OH abstraction followed by bimolecular RO2 reaction) on aerosol formation from DMS. Due to the presence of common intermediate species, the oxidation of dimethyl sulfoxide (DMSO) and dimethyl disulfide (DMDS) can shed light on these two DMS reaction channels; they are also both atmospherically relevant species in their own right. This work examines the OH oxidation of DMSO and DMDS, using chamber experiments monitored by chemical ionization mass spectrometry and aerosol mass spectrometry to study the full range of sulfur-containing products across a range of NO concentrations. The oxidation of both compounds is found to lead to rapid aerosol formation (which does not involve the intermediate formation of SO2), with a substantial fraction (14 %–47 % S yield for DMSO and 5 %–21 % for DMDS) of reacted sulfur ending up in the particle phase and the highest yields observed under elevated NO conditions. Aerosol is observed to consist mainly of sulfate, methanesulfonic acid, and methanesulfinic acid. In the gas phase, the NOx dependence of several products, including SO2 and S2-containing organosulfur species, suggest reaction pathways not included in current mechanisms. Based on the commonalities with the DMS oxidation mechanism, DMSO and DMDS results are used to reconstruct DMS aerosol yields; these reconstructions roughly match DMS aerosol yield measurements from the literature but differ in composition, underscoring remaining uncertainties in sulfur chemistry. This work indicates that both the abstraction and addition channels contribute to rapid aerosol formation from DMS and highlights the need for more study into the fate of small sulfur radical intermediates (e.g., CH3S, CH3SO2, and CH3SO3) that are thought to play central roles in the DMS oxidation mechanism.

Goss, Matthew B. (ORCID:0000000226885463)↗
DOE OSTI2024

Contribution of expanded marine sulfur chemistry to the seasonal variability of dimethyl sulfide oxidation products and size-resolved sulfate aerosol

Marine emissions of dimethyl sulfide (DMS) and the subsequent formation of its oxidation products methanesulfonic acid (MSA) and sulfuric acid (H 2 SO 4 ) are well-known natural precursors of atmospheric aerosols, contributing to particle mass and cloud formation over ocean and coastal regions. Despite a long recognized and well-studied role in the marine troposphere, DMS oxidation chemistry remains a work in progress within many current air quality and climate models, with recent advances exploring heterogeneous chemistry and uncovering previously unknown intermediate species. With the identification of additional DMS oxidation path ways and intermediate species that influence the eventual fate of DMS, it is important to understand the impact of these pathways on the overall sulfate aerosol budget and aerosol size distribution. In this work, we update and evaluate the DMS oxidation mechanism of the chemical transport model GEOS-Chem by implementing expanded DMS oxidation pathways in the model. These updates include gas- and aqueous-phase reactions, the formation of the intermediates dimethyl sulfoxide (DMSO) and methanesulfinic acid (MSIA), and cloud loss and aerosol uptake of the recently quantified intermediate hydroperoxymethyl thioformate (HPMTF). We find that this updated mechanism collectively decreases the global mean surface-layer gas-phase sulfur dioxide (SO 2 ) mixing ratio by 40 % and enhances the sulfate aerosol ($SO^{2-}_{4}$) mixing ratio by 17 %. We further perform sensitivity analyses exploring the contribution of cloud loss and aerosol uptake of HPMTF to the overall sulfur budget. Comparing modeled concentrations to available observations, we find improved biases relative to previous studies. To quantify the impacts of these chemistry updates on global particle size distributions and the mass concentration, we use the TwO-Moment Aerosol Sectional (TOMAS) aerosol microphysics module coupled to GEOS-Chem and find that changes in particle formation and growth affect the size distribution of aerosol. With this new DMS-oxidation scheme, the global annual mean surface-layer number concentration of particles with diameters smaller than 80 nm decreases by 16.8 %, with cloud loss processes related to HPMTF being mostly responsible for this reduction. However, the global annual mean number of particles larger than 80 nm (corresponding to particles capable of acting as cloud condensation nuclei, CCN) increases by 3.8 %, suggesting that the new scheme promotes seasonal particle growth to these sizes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Global ocean dimethyl sulfide climatology estimated from observations and an artificial neural network

Marine dimethyl sulfide (DMS) is important to climate due to the ability of DMS to alter Earth's radiation budget. Knowledge of the global-scale distribution, seasonal variability, and sea-to-air flux of DMS is needed in order to improve understanding of atmospheric sulfur, aerosol/cloud dynamics, and albedo. Here we examine the use of an artificial neural network (ANN) to extrapolate available DMS measurements to the global ocean and produce a global climatology with monthly temporal resolution. A global database of 82 996 ship-based DMS measurements in surface waters was used along with a suite of environmental parameters consisting of latitude–longitude coordinates, time of day, time of year, solar radiation, mixed layer depth, sea surface temperature, salinity, nitrate, phosphate, and silicate. Linear regressions of DMS against the environmental parameters show that on a global-scale mixed layer depth and solar radiation are the strongest predictors of DMS. These parameters capture ~9 % and ~7 % of the raw DMS data variance, respectively. Multilinear regression can capture more of the raw data variance (~39 %) but strongly underestimates DMS in high-concentration regions. In contrast, the artificial neural network captures ~66 % of the raw data variance in our database. Like prior climatologies our results show a strong seasonal cycle in surface ocean DMS with the highest concentrations and sea-to-air fluxes in the high-latitude summertime oceans. We estimate a lower global sea-to-air DMS flux (20.12±0.43 Tg S yr –1 ) than the prior estimate based on a map interpolation method when the same gas transfer velocity parameterization is used. Our sensitivity test results show that DMS concentration does not change unidirectionally with each of the environmental parameters, which emphasizes the interactions among these parameters. The ANN model suggests that the flux of DMS from the ocean to the atmosphere will increase with global warming. Given that larger DMS fluxes induce greater cloud albedo, this corresponds to a negative climate feedback.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Methods of making and inspecting a web of vitreous lithium sulfide separator sheet and lithium electrode assemblies

A lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and/or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner. An automated machine based system, apparatus and methods assessing and inspecting the quality of such vitreous solid electrolyte sheets, electrode sub-assemblies and lithium electrode assemblies can be based on spectrophotometry and can be performed inline with fabricating the sheet or web (e.g., inline with drawing of the vitreous Li ion conducting glass) and/or with the manufacturing of associated electrode sub-assemblies and lithium electrode assemblies and battery cells.

25 ENERGY STORAGE↗
DOE OSTI2020

Methods of producing metal sulfides, metal selenides, and metal sulfides/selenides having controlled architectures using kinetic control

The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q1, Q2, Q3, R1, R2, R3, R5, and X are defined within the specification.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Cadmium sulfide quantum dots

Provided herein are compositions comprising cadmium sulfide quantum dot photocatalysts and methods and systems utilizing as much (e.g., for the reduction of a nitrobenzene to an aniline).

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2020

Standalone sulfide based lithium ion-conducting glass solid electrolyte and associated structures, cells and methods

A standalone lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and/or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner.

Visco, Steven J.↗
DOE OSTI2023

Methods and materials for protection of sulfide glass solid electrolytes

A sulfide glass solid electrolyte sheet can be protected from reaction with moisture by a thin metal layer coating converted to a thin electrochemically functional and protective compound layer. The converted protective compound layer is electrochemically functional in that it allows for through transport of lithium ions.

Visco, Steven J.↗
DOE OSTI2023

Standalone sulfide based lithium ion-conducting glass solid electrolyte and associated structures, cells and methods

A standalone lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and/or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner.

Visco, Steven J.↗