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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 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Accessibility and Mechanical Stability of Nanoporous Zinc Oxide and Aluminum Oxide Coatings Synthesized via Infiltration of Polymer Templates

The conformal nanoporous inorganic coatings with accessible pores that are stable under applied thermal and mechanical stresses represent an important class of materials used in the design of sensors, optical coatings, and biomedical systems. Here, we synthesize porous AlO x and ZnO coatings by the sequential infiltration synthesis (SIS) of two types of polymers that enable the design of porous conformal coatings—polymers of intrinsic microporosity (PIM) and block co-polymer (BCP) templates. Using quartz crystal microbalance (QCM), we show that alumina precursors infiltrate both polymer templates four times more efficiently than zinc oxide precursors. Using the quartz crystal microbalance (QCM) technique, we provide a comprehensive study on the room temperature accessibility to water and ethanol of pores in block copolymers (BCPs) and porous polymer templates using polystyrene-block-poly-4-vinyl pyridine (PS75-b-P4VP25) and polymers of intrinsic microporosity (PIM-1), polymer templates modified by swelling, and porous inorganic coatings such as AlO x and ZnO synthesized by SIS using such templates. Importantly, we demonstrate that no structural damage occurs in inorganic nanoporous AlO x and ZnO coatings synthesized via infiltration of the polymer templates during the water freezing/melting cycling tests, suggesting excellent mechanical stability of the coatings, even though the hardness of the inorganic nanoporous coating is affected by the polymer and precursor selections. We show that the hardness of the coatings is further improved by their annealing at 900 °C for 1 h, though for all the cases except ZnO obtained using the BCP template, this annealing has a negligible effect on the porosity of the material, as is confirmed by the consistency in the optical characteristics. These findings unravel new potential for the materials being used across various environment and temperature conditions.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Digital light processing of porous LLZTO scaffolds for Li-garnet solid-state batteries

Li 7 La 3 Zr 2 O 12 (LLZO)-based solid-state electrolytes (SEs) are promising materials for next-generation solid-state batteries. In this work, digital light processing (DLP), an emerging additive manufacturing technology, is employed to produce porous Ta-doped LLZO (LLZTO) scaffolds. The self-standing scaffolds are 100 μm thick and have 40% porosity. The scaffolds demonstrate symmetric cell cycling stability exceeding 1,500 h at 0.1 mA/cm2 current density, with a capacity of 0.1 mAh/cm 2 (1 h for each half cycle). At higher current densities, reversible soft shorts frequently happen, while immediate hard shorts are prevented due to Li dendrite growth being hindered by the tortuous pore network. In addition to the cycling stability, the phase stability of LLZTO is investigated during the post-printing thermal process for printing resin removal. We discovered that the LLZTO partially decomposes into Li 2 Zr 2 O 7 and other impurity phases from 400°C to 800°C, but the pure LLZTO phase is restored upon the completion of resin removal beyond 800°C.

Li-metal anode↗
DOE OSTI2024

Scalable Graphene Oxide Hollow Fiber Membranes for Dye Desalination Enabled by Multi‐Purpose Polyamine Functionalization

2D nanosheets such as graphene oxide (GO) can be stacked to construct membranes with fine-tuned nanochannels to achieve molecular sieving ability. These membranes are often thin to achieve high water permeance, but their fabrication with consistent nanostructures on a large scale presents an enormous challenge. Herein, GO-based hollow fiber membranes (HFMs) are developed for dye desalination by synergistically combining chemical etching to form in-plane nanopores (10–30 nm) to increase water permeance and polyamine functionalization to improve underwater stability and enable facile large-scale production using existing membrane manufacturing processes. HFM modules with areas of 88 cm 2 and GO layer thicknesses of ≈500 nm are fabricated, and they exhibited a stable dye water permeance of 75 L m −2 h −1 bar −1 , rejection of >99.5% for Direct red and Congo red, and Na 2 SO 4 /dye separation factor of 300–500, superior to state-of-the-art commercial membranes. Furthermore, the versatility of this approach is also demonstrated using different short polyamines and porous substrates. This study reveals a scalable way of designing 2D materials into high-performance robust membranes for practical applications.

amine functionalization↗
DOE OSTI2026

Time-Resolved Neutron Imaging for Hydrogen Uptake in Subsurface Lithologies

Geologic hydrogen production and underground storage are increasingly important for meeting rising energy demands while providing clean-combustion advantages. However, hydrogen’s high diffusivity and propensity for leakage through porous media necessitate direct evaluation of its transport behavior in subsurface materials. Whereas X-ray microcomputed tomography (μCT) studies often employ contrast agents or surrogate gases, this study leverages neutron transmission radiography/CT to observe hydrogen migration in situ. This work represents the first demonstration of real-time neutron radiography of hydrogen migration in reservoir and caprock lithologies. Cylindrical cores of Indiana limestone, Amherst Gray sandstone, and Tumey shale were subjected to constant-pressure hydrogen charging and scanned in real time using high-resolution neutron radiography. Results indicate immediate hydrogen infiltration in sandstone and limestone, with homogeneous distribution detected throughout their pore structure. In contrast, hydrogen remained largely absent from fine-grained shale under the same pressure, except in an apparently localized fracture zone, where neutron signatures confirmed the presence of hydrogen. Subsequent neutron CT of the sandstone sample, using image subtraction against an uncharged reference, corroborated hydrogen distribution patterns. Even under lowpressure, single-phase conditions, distinct neutron imaging signatures of hydrogen were achieved. These preliminary findings underscore the potential of neutron imaging for advancing subsurface hydrogen migration research.

08 HYDROGEN↗
DOE OSTI2020

The nature and origins of decametre-scale porosity in Ordovician carbonate rocks, Halahatang oilfield, Tarim Basin, China

At >7 km depths in the Tarim Basin, hydrocarbon reservoirs in Ordovician rocks of the Yijianfang Formation contain large cavities ( c . 10 m or more), vugs, fractures and porous fault rocks. Although some Yijianfang Formation outcrops contain shallow (formed near surface) palaeokarst features, cores from the Halahatang oilfield lack penetrative palaeokarst evidence. Outcrop palaeokarst cavities and opening-mode fractures are mostly mineral filled but some show evidence of secondary dissolution and fault rocks are locally highly ( c . 30%) porous. Cores contain textural evidence of repeated formation of dissolution cavities and subsequent filling by cement. Calcite isotopic analyses indicate depths between c . 220 and 2000 m. Correlation of core and image logs shows abundant cement-filled vugs associated with decametre-scale fractured zones with open cavities that host hydrocarbons. A Sm–Nd isochron age of 400 ± 37 Ma for fracture-filling fluorite indicates that cavities in core formed and were partially cemented prior to the Carboniferous, predating Permian oil emplacement. Repeated creation and filling of vugs, timing constraints and the association of vugs with large cavities suggest dissolution related to fractures and faults. In the current high-strain-rate regime, corroborated by velocity gradient tensor analysis of global positioning system (GPS) data, rapid horizontal extension could promote connection of porous and/or solution-enlarged fault rock, fractures and cavities. Supplementary material: Stable isotopic analyses and the velocity gradient tensor and principal direction and magnitude calculation are available at https://doi.org/10.6084/m9.figshare.c.4946046 Thematic collection: This article is part of the The Geology of Fractured Reservoirs collection available at: https://www.lyellcollection.org/cc/the-geology-of-fractured-reservoirs

Geology↗
DOE OSTI2022

Lithium extraction composite for recovery of lithium from brines, and process of using said composition

A lithium extraction composite comprising: (i) a porous support and (ii) particles of a lithium-selective sorbent material coated on at least one surface of the support, wherein the support has a planar membrane, fiber (or rod), or tubular shape. A method for extracting and recovering a lithium salt from an aqueous solution by use of the above-described composition is also described, the method comprising (a) flowing the aqueous source solution through a first zone or over a first surface of the lithium extraction composite to result in selective lithium intercalation in the lithium-selective sorbent material in the first zone or first surface; and (b) simultaneously recovering lithium salt extracted in step (a) from said lithium-selective sorbent material by flowing an aqueous stripping solution through a second zone or over a second surface of the lithium extraction composite in which lithium ions from the first zone or first surface diffuse.

Bhave, Ramesh R.↗
DOE OSTI2019

Boosting Superior Lithium Storage Performance of Alloy-Based Anode Materials via Ultraconformal Sb Coating–Derived Favorable Solid-Electrolyte Interphase

Alloy materials such as Si and Ge are attractive as high-capacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during discharge-charge processes. Compared to the over-emphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solid-electrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloy-based anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li 3 Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiF-dominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sb-coated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh g -1 after 200 cycles at 500 mA g -1 , compared to only 72% and 170 mAh g -1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve long-term cycling stability for alloy-based anode materials.

25 ENERGY STORAGE↗
DOE OSTI2021

1-D NiO nanorods pillared 2-D MnO 2 nanosheets as lithium-free cathode materials for charged-state lithium batteries

Theoretically monolayer MnO 2 sheets have an impressive high capacity of 616 mAh/g, but practically monolayer MnO 2 sheets have poor performances due partially to monolayer restacking. In this paper, we report the preparation of three-dimensional porous NiO nanorod pillared δ-MnO 2 nanosheets as integrated nanoarchitectures as lithium-free cathode materials. The as-synthesized NiO pillared δ-MnO 2 nanosheets have resulted in a moderately high specific capacity of 185 mA h g –1 , with more than 63% capacity retention after 200 cycles. In comparison, 2D MnO 2 nanosheets without NiO pillared structures only achieved a low initial capacity of 137 mA h g –1 , with just 17% capacity retention after 200 cycles. The dramatically improved electrochemical performances could be attributed to high surface areas with excellent porosity which provides more electrochemically active sites and thermodynamically favorable insertion pathways for the lithium ions. Furthermore, our results reveal that insertion of pillars is a promising strategy to explore in order to mitigate the restacking issues and achieve electrochemical performances close to theoretical values for monolayer MnO 2 .

25 ENERGY STORAGE↗
DOE OSTI2022

Nitrogen-sulfur-carbon nanocomposites and their application as cathode materials in lithium-sulfur batteries

The invention is directed in a first aspect to electron-conducting porous compositions comprising an organic polymer matrix doped with nitrogen atoms and having elemental sulfur dispersed therein, particularly such compositions having an ordered framework structure. The invention is also directed to composites of such S/N-doped electron-conducting porous aromatic framework (PAF) compositions, or composites of an S/N-doped mesoporous carbon composition, which includes the S/N-doped composition in admixture with a binder, and optionally, conductive carbon. The invention is further directed to cathodes for a lithium-sulfur battery in which such composites are incorporated.

25 ENERGY STORAGE↗
DOE OSTI2022

Natural colloids facilitated transport of steroidal estrogens in saturated porous media: Mechanism and processes

Steroid estrogens (SEs) are widely distributed in terrestrial environment, whilst the transport of SEs in groundwater is not well understood. Specifically, the effects of ubiquitous natural colloids on the SEs transport are unclear. Here, the influence of inorganic colloids (i.e. silica and illite) and organic colloids, i.e. Humic acid (HA), on the transport of estrone (E1) and estradiol (E2) in saturated porous media were studied in laboratory scale column experiments. Characterization on the colloids and the column packing material was conducted to provide bases for the interpretation of column test findings. Results showed that the transport of SEs was facilitated by the nature colloids that were migrating through the saturated porous media. About 38.5% of E1 and 24.6% of E2 were retained in the column when colloids were absent in the system. Further, when transporting with silica colloids, illite colloids, and HA colloids, the transport of E1 was enhanced by 15.64%, 11.17%, and 25.60%, respectively; whilst the transport of E2 was improved by 19.56%, 23.06%, and 36.40%, respectively. The colloids’ SEs transport enhancement depended not only on the mobility of the colloids but also on their geochemical characteristics. The tested organic colloids showed 1.5-2.5 times greater ability on promoting the transport of SEs than the inorganic ones. The proposed mechanisms of nature colloids facilitated transport of SEs include competing for adsorption sites on the sand surfaces by the colloids resulting mobilization of adsorbed SEs from solid matrix, and transport of colloids as carriers for SEs.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Enhanced delivery of engineered Fe-Mn binary oxides in heterogeneous porous media for efficient arsenic stabilization

Heterogeneity in sediment and aquifer is universal, resulting in preferential flows of injected materials in the high permeability regions and forming flow by-passed zones in the low permeability regions during in-situ subsurface remediation. This adverse effect can considerably delay the completion of remedial operations and significantly increase the cost. Column experiments were designed and conducted to study the transport of starch- and starch-xanthan gum modified Fe-Mn binary oxide particles (SFM and SXFM) in saturated heterogeneous porous media and to reveal the particles’ arsenic (As) stabilization performance. Fine-in-Coarse (FIC) and Coarse-in-Fine (CIF) patterns of heterogeneous packings were set up in the columns. Testing results demonstrated that starch-xanthan gum dual treatment on Fe-Mn binary oxides successfully improved the particles’ migration capability in heterogeneous porous media and their distribution uniformity attributed to the profound shear thinning behavior of xanthan gum solution. The addition of xanthan gum to the system increased the viscosity and shear thinning property of SXFM suspension, making it a better candidate for delivery. Both SFM and SXFM stabilized As in heterogeneously packed sediment collected from a contaminated site, with SXFM showing better stabilization performance than SFM. The stabilization effects of SXFM were 90.7-97.0%, compared to 82.0-95.2% of SFM.

Yan, Xiulan↗
DOE OSTI2022

Hermetically sealed porous-wall hollow microspheres enabled by monolithic glass coatings: Potential for thermal insulation applications

Thermal insulation materials are crucial to improve the energy performance of buildings and industrial applications. We report an approach to create hermetically vacuum-sealed silica-based hollow microspheres that can lower the thermal conductivity of closed-cell insulation materials. The wall structure of these hollow microspheres includes a reticulated network of pores or channels that extend through the thickness of the wall. When a thin layer of glass material is applied to the wall exterior, followed by a vacuum-assisted thermal treatment process, the coated microsphere surfaces display a highly dense conformal coverage and near-complete elimination of surface porosity. The sealing efficiency of these microspheres is verified by trapping argon within their cavities as well as through evacuating their hollow cores. Notably, incorporating the evacuated microspheres into a polymer matrix resulted in ~27% enhancement in its thermal insulation performance and no notable loss of performance was observed following three months of exposure to ambient conditions. Thus, we believe that the present study offers a commercially viable strategy that opens the door to applications of such inorganic hollow particles in areas ranging from vacuum-based thermal insulation systems to catalysis, separation technologies, and medical fields.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Three-dimensional hierarchically porous MoS 2 foam as high-rate and stable lithium-ion battery anode

Architected materials that actively respond to external stimuli hold tantalizing prospects for applications in energy storage, wearable electronics, and bioengineering. Molybdenum disulfide, an excellent two-dimensional building block, is a promising candidate for lithium-ion battery anode. However, the stacked and brittle two-dimensional layered structure limits its rate capability and electrochemical stability. Here we report the dewetting-induced manufacturing of two-dimensional molybdenum disulfide nanosheets into a three-dimensional foam with a structural hierarchy across seven orders of magnitude. Our molybdenum disulfide foam provides an interpenetrating network for efficient charge transport, rapid ion diffusion, and mechanically resilient and chemically stable support for electrochemical reactions. These features induce a pseudocapacitive energy storage mechanism involving molybdenum redox reactions, confirmed by in-situ X-ray absorption near edge structure. The extraordinary electrochemical performance of molybdenum disulfide foam outperforms most reported molybdenum disulfide-based Lithium-ion battery anodes and state-of-the-art materials. This work opens promising inroads for various applications where special properties arise from hierarchical architecture.

25 ENERGY STORAGE↗
DOE OSTI2020

Highly Reversible Plating/Stripping of Porous Zinc Anodes for Multivalent Zinc Batteries

Zinc continues to garner immense interest due to its versatility as an anode material in several configurations utilizing either alkaline or mild-pH electrolytes. Current research on using mild-pH electrolytes has improved the rechargeability aspect of Zn-based batteries since Zn2+ is solely utilized for plating/stripping of Zn. Several studies have incorporated Zn metal foils, yet, dramatic improvements can be achieved by expressing Zn as a porous structure. Herein, we use a quasi-pulsed electrodeposition process to prepare a conformal Zn coating onto 3D porous copper foam. By tuning the electrodeposition parameters, we achieved an optimal Zn coating that undergoes reversible plating/stripping when tested in symmetric Zn cells, which supported a low overpotential of ~60 mV for up to 100 cycles. We further investigated changes in the surface morphology by studying the Zn surface of both foil and 3D structure using scanning electron microscopy and X-ray micro-computed tomography. Both techniques showed that the Zn foil undergoes dramatic alterations at the surface, which results in inhomogeneous deposition of Zn, whereas the 3D form exhibited minimal changes. Lastly, we paired both Zn foil and 3D Zn with vanadium oxide and demonstrated that the porous structure supports high rate capability and high specific capacity.

25 ENERGY STORAGE↗
DOE OSTI2023

Porous and Water Stable 2D Hybrid Metal Halide with Broad Light Emission and Selective H 2 O Vapor Sorption

Abstract In this work we report a strategy for generating porosity in hybrid metal halide materials using molecular cages that serve as both structure‐directing agents and counter‐cations. Reaction of the [2.2.2] cryptand (DHS) linker with Pb II in acidic media gave rise to the first porous and water‐stable 2D metal halide semiconductor (DHS) 2 Pb 5 Br 14 . The corresponding material is stable in water for a year, while gas and vapor‐sorption studies revealed that it can selectively and reversibly adsorb H 2 O and D 2 O at room temperature (RT). Solid‐state NMR measurements and DFT calculations verified the incorporation of H 2 O and D 2 O in the organic linker cavities and shed light on their molecular configuration. In addition to porosity, the material exhibits broad light emission centered at 617 nm with a full width at half‐maximum (FWHM) of 284 nm (0.96 eV). The recorded water stability is unparalleled for hybrid metal halide and perovskite materials, while the generation of porosity opens new pathways towards unexplored applications ( e.g . solid‐state batteries) for this class of hybrid semiconductors.

Azmy, Ali↗
DOE OSTI2025

Recent Advances and Future Perspectives of Low-Concentration CO 2 Enrichment and Emerging Applications

Low-concentration carbon dioxide (LCCO 2 ) streams, ranging from ambient air to industrial flue gas, represent a significant yet underutilized carbon resource. This review examines recent advances in technologies for enriching LCCO 2 and enabling its integration into a wide range of applications. It covers emerging materials and processes for CO 2 capture, including immobilized amines, metal oxides, polymers, porous carbons, and zeolites, with a focus on performance metrics, regeneration strategies, and process intensification. Beyond capture, the review explores the direct utilization of LCCO 2 through reactive capture pathways enabled by novel catalysts and processes, as well as nonreactive applications, such as greenhouse cultivation, enhanced weathering, and sustainable agriculture. Additionally, this review highlights the role of LCCO 2 in enhancing critical metal recovery. Finally, the review outlines crucial future research directions necessary to fully realize LCCO 2 enrichment’s potential within circular carbon economies and critical material supply chains, paving the way toward a more energy-innovative and resource-resilient industrial sector. The findings are significant for researchers in academia, industry, and government, as well as the public interested in extending the value of LCCO 2 .

atmospheric chemistry↗