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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 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Mechanically Robust Bismuth-Embedded Carbon Microspheres for Ultrafast Charging and Ultrastable Sodium-Ion Batteries

Advancements in the development of fast-charging and long-lasting microstructured alloying anodes with high volumetric capacities are essential for enhancing the operational efficiency of sodium-ion batteries (SIBs). These anodes, however, face challenges such as declined cyclability and rate capability, primarily due to mechanical degradation reduced by significant volumetric changes (over 252%) and slow kinetics of sodium-ion storage. Herein, we introduce a novel anode design featuring densely packed bismuth (Bi) embedded within highly conductive carbon microspheres to overcome the aforementioned challenges. Remarkably, the high loading Bi anode within carbon microspheres with a high tap density of 2.59 g cm -3 possesses significant mechanical strength exceeding 590 MPa and limits volume swelling of only 10.9% post-sodiation. This anode demonstrates a high volumetric capacity (908.3 mAh cm -3 ), ultrafast chargeability (200 A g -1 , full charge/discharge in just 5.5 s), and outstanding cyclability over 12,000 cycles and maintains exceptional cycling stability even at -30 °C. The full cell paired with a Na 3 V 2 (PO 4 ) 3 cathode retains over 80% capacity after 600 cycles at 36 C, demonstrating a remarkable rate capability of 126 C (full charge/discharge in 28.6 s). Our comprehensive experimental evaluations and chemo-mechanical simulations shed light on the mechanisms underpinning the anode's superior performance. In conclusion, this development marks a significant advancement in the design of durable and fast-charging anodes for high-performance SIBs.

25 ENERGY STORAGE↗
DOE OSTI2020

High capacity and stable cathode materials

High energy density cathode materials, such as LiNixMnyCozO2 (NMC) cathode materials, with improved discharge capacity (hence energy density) and enhanced cycle life are described. A solid electrolyte, such as lithium phosphate infused inside of secondary particles of the cathode material demonstrates significantly enhanced structural integrity without significant or without any observable particle cracking occurring during charge/discharge processes, showing high capacity retention of more than 90% after 200 cycles at room temperature. In certain embodiments the disclosed cathode materials (and cathodes made therefrom) are formed using nickel-rich NMC and/or are used in a battery system with a non-aqueous dual-Li salt electrolytes.

25 ENERGY STORAGE↗
DOE OSTI2022

Astragaloside IV improved antioxidative stress capacity and related gene expression of the Keap1‐Nrf2 pathway in grass carp ( Ctenopharyngodon idella ) hepatocytes under heat stress

Abstract This study aims to investigate the protective effects of astragaloside IV (AS‐IV) on the hepatocytes of grass carp ( Ctenopharyngodon idella ) on heat stress. Cultured cells were treated with AS‐IV (0, 50, 100 and 200 μg/ml) at 28°C for 24 h and then exposed to heat stress by increasing the culturing temperature (32 ± 0.5°C) for 6 h. The increased temperatures significantly reduced cell viability and superoxide dismutase (SOD) activity, and increased malondialdehyde (MDA) levels in the 0 μg/ml AS‐IV treatment group at 32°C, but the grass carp hepatocytes treated with 100 and 200 μg/ml AS‐IV had significantly increased cell viability and SOD activity and decreased MDA levels. The mRNA levels of keap1a , keap1b , nrf2 , gsh‐px , cat , cu‐zn sod , mgst1 and il‐6 were significantly lower in the 0 μg/ml AS‐IV treatment group at 32°C, while those of keap1a , nrf2 , gsh‐px , cat , cu‐zn sod , gstp1 , ho‐1 and il‐6 were significantly higher in cells treated with 100 or 200 μg/ml AS‐IV. Our findings indicate that AS‐IV could enhance the antioxidative stress capacity of grass carp hepatocytes under heat stress, and its mechanism may be associated with the activation of the Keap1‐Nrf2 pathway. Thus, these results provide new insights into how to alleviate heat stress in grass carp.

Liu, Hua↗
NASA NTRS2005

Analysis of Wake VAS Benefits Using ACES Build 3.2.1: VAMS Type 1 Assessment

The FAA and NASA are currently engaged in a Wake Turbulence Research Program to revise wake turbulence separation standards, procedures, and criteria to increase airport capacity while maintaining or increasing safety. The research program is divided into three phases: Phase I near term procedural enhancements; Phase II wind dependent Wake Vortex Advisory System (WakeVAS) Concepts of Operations (ConOps); and Phase III farther term ConOps based on wake prediction and sensing. The Phase III Wake VAS ConOps is one element of the Virtual Airspace Modelling and Simulation (VAMS) program blended concepts for enhancing the total system wide capacity of the National Airspace System (NAS). This report contains a VAMS Program Type 1 (stand-alone) assessment of the expected capacity benefits of Wake VAS at the 35 FAA Benchmark Airports and determines the consequent reduction in delay using the Airspace Concepts Evaluation System (ACES) Build 3.2.1 simulator.

Smith, Jeremy C.↗
DOE OSTI2025

Minimizing Inter‐Lattice Strain to Stabilize Li‐Rich Cathode by Order–Disorder Control

Li-rich Mn-based layered (LMR) cathodes with anionic redox chemistry show great potential for next-generation sustainable Li-ion battery (LIB) applications due to the low cost and high energy density. However, the asynchronous structural evolutions with cycling in the heterogeneous composite structure of LMR lead to serious lattice strain and thus fast electrochemical decay, which hinders the commercialization of LMR cathodes. Here, in this study, an order–disorder coherent LMR cathode is demonstrated that exhibits a higher average voltage (by 0.25 V), negligible voltage decay (97.6% voltage retention after 100 cycles at 100 mA g −1 ), and enhanced cycling stability (98% capacity retention after 200 cycles at 100 mA g −1 ) compared to its layered oxide counterparts. It is proposed that this order–disorder coherent structure design can promote a more synchronous and homogeneous structure evolution during charge and discharge, thus minimizing lattice strain, which significantly prevents layer collapse and collective degradation at high voltage, improving the electrochemical stability. The study displays the feasibility of optimizing the performance of Li-rich cathode materials through a dedicated order–disorder structure control for sustainable energy storage.

Xu, Shenyang [Peking University, Shenzhen (China)]↗
DOE OSTI2022

Synergistic degradation performance of UV / TiO 2 photocatalysis and biotrickling filtration inoculated with Aspergillus sp. S1 for gaseous m ‐xylene

Abstract Background Biotricking filtration (BTF) based on absorption and biodegradation of waste gas by microorganisms in a biofilm can be used to degrade with difficulty hydrophobic volatile pollutants. Photocatalysis is a promising technology for the abatement of gaseous contaminants because of its nonselective oxidation of volatile organic compounds; however, photocatalysis technology has the limitations of high energy consumption and low mineralization efficiency. This study, therefore, aimed to investigate the synergistic effects of UV/TiO 2 photocatalysis (PCO) pretreatment and BTF in treating gaseous m ‐xylene. Results BTF incubated with a mold, Aspergillus sp. S1, was acclimated with m ‐xylene as the sole carbon source. A combined system of PCO with BTF was developed to remove gaseous m ‐xylene. The results showed that the startup period was shortened by 3 days in the PCO‐BTF combined system compared to that with BTF alone. The removal efficiency reached 73% and 91% for the BTF and PCO‐BTF systems respectively when the empty bed residence time was extended to 90 s. In addition, PCO‐BTF could withstand transient shock loading of m ‐xylene of 5000 mg m −3 and gradually restore its decontamination performance. Conclusions PCO pretreatment was effective in the enhancement of the removal capacity of BTF for m ‐xylene. The PCO‐BTF system proposed in this study provides an attractive alternative to abate hydrophobic volatile pollutants. The integration of PCO essentially prompted the capability of Aspergillus sp. S1 in the BTF unit, which paves the way for the treatment of gaseous waste at an industrial scale. © 2022 Society of Chemical Industry (SCI).

Du, Qingping↗
DOE OSTI2025

Post synthetic amine functionalization of MOF-808 for CO 2 sorption via ligand exchange and Michael addition

Post synthetic modification of metal organic frameworks presents a viable route for amine functionalization which can significantly enhance CO 2 sorption capacity. We present a facile means of amine incorporation using limited synthetic steps and low-cost reagents that results in a high density of primary alkyl amines distributed through a zirconium-based metal organic framework (MOF). Both the MOF synthesis and the post synthetic modification take place under aqueous conditions and result in strongly bound molecular amines available for sorbate interaction throughout the MOF pores. Furthermore, this amine incorporation protocol results in a significantly increased CO 2 capacity compared with the unmodified MOF-808. Specifically, CO 2 isotherms collected at 298 K for the unmodified MOF-808 show uptakes of 0.06, 0.2, and 1.2 mmol/g at 4, 15, and 100 kPa, respectively, which can be compared with 0.3, 0.7, and 2.5 mmol/g for the glycine grafted MOF-808 and 0.5, 0.9, and 2.3 mmol/g for ethylenediamine grafted MOF-808.

Amine sorbent↗
DOE OSTI2020

Crystalline Loading of Lipophilic Coenzyme Q10 Pharmaceuticals within Conjugated Carbon Aerogel Derivatives

Low-density aerogel materials currently are being considered for applications in controlling the rate of release for small-molecule pharmaceuticals in vivo. In particular, silica (SiO2) aerogels are an intriguing platform for controlling both the absolute amount of drug loading, but also the crystalline state of small molecule pharmaceuticals has been shown to affect drug release kinetics. To date, loading silica aerogel materials with crystalline pharmaceuticals typically require dissolving small molecules in a supercritical solvent (i.e., CO2) before drying to recover the aerogel/drug composite. Here we demonstrate a simple and low-cost method for controlling the crystallinity of the model drug coenzyme Q10 (CoQ10) within carbon aerogel materials by rationally controlling the chemical microstructure of the aerogel to exhibit ?-conjugated (sp2) chemical bonding. In particular, both pyrolyzed graphene and nanodiamond aerogels exhibit enhanced intrinsic drug loading capacity and CoQ10 crystallinity over a broad range of sp2 surface-curvature. In contrast, amorphous carbon aerogel materials are observed to load CoQ10 pharmaceuticals with strictly amorphous microstructure.

Lim, Mathew↗
DOE OSTI2025

Expanding the interlayer spacing of MXene through nanoarchitecture design

MXenes, a diverse class of two-dimensional transition metal carbides and nitrides with distinct surface chem istries, offer remarkable electrochemical and physicochemical properties. Yet, their performance can be hindered by the intrinsic restacking of layers, which restricts surface activity. This review outlines recent advances in interlayer spacing modulation strategies designed to overcome this limitation. A wide range of guest spe cies–including mono- and polyatomic ions, small molecules, low-dimensional nanomaterials, and polymers–are discussed with respect to their intercalation mechanisms, structural effects, and capacity to introduce functional enhancements. These intercalating species interact with MXene via electrostatic forces, hydrogen bonding, redox reactions, or covalent linkages, resulting in stable, expanded nanoarchitectures. The influence of expanded spacing on capacitive behavior is briefly highlighted to illustrate its practical relevance. Although Ti 3 C 2 T x is currently the most extensively investigated MXene, applying these interlayer engineering strategies to other MXene compositions will be essential for accessing a wider range of properties and functionalities.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Selective single-atom adsorption for precision separation of lead ions in tap water via capacitive deionization

Capacitive deionization (CDI) offers a cost-effective and low-energy method for selective removal of Pb 2+ from drinking water. Modifying CDI electrode surfaces with functional groups presents a versatile approach to enhancing selective ion adsorption capacity. However, a comprehensive understanding of the selectivity and removal efficiency of Pb 2+ among diverse functional groups remains unexplored. Here, we investigated the effects of different functional groups (-SH, -COOH, and -NH 2 ) attached to the graphene oxide (GO) electrode surfaces on Pb 2+ selectivity and removal efficiency. Surprisingly, GO-COOH demonstrated single-atom adsorption of Pb 2+ , displaying superior removal efficiency and selectivity compared with -SH and -NH 2 , although -SH possesses significant chelation capability for Pb 2+ . Both density functional theory (DFT) calculations and X-ray pair distribution function (PDF) analyses confirmed that Pb 2+ exhibits a theoretically higher affinity to -COOH. Further, this research deepens our understanding of the interactions between functional groups and heavy metal ions, enabling selective and rapid separation of target cations for water purification.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Direct Observation of Phase Change Accommodating Hydrogen Uptake in Bimetallic Nanoparticles

Hydrogen holds great promise as a cleaner alternative to fossil fuels, but its efficient and affordable storage remains a significant challenge. Bimetallic systems, such as Pd and Ni, present a promising option for storing hydrogen. In this study, using the combination of different cutting-edge X-ray and electron techniques, we observed the transformations of Pd–Ni nanoparticles, which initially consist of a NiO-rich shell surrounding a Pd-rich core but undergo a major transformation when they interact with hydrogen. During hydrogen exposure, the Pd core breaks into smaller pockets, dramatically increasing its surface area and enhancing the hydrogen storage capacity, especially in nanoparticles with lower Pd content. The findings provide a deep understanding of the morphological changes at the atomic level during hydrogen storage and contribute to designing cost-effective hydrogen storage using multimetallic systems.

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

Designing electrolytes with high solubility of sulfides/disulfides for high-energy-density and low-cost K-Na/S batteries

Alkaline metal sulfur (AMS) batteries offer a promising solution for grid-level energy storage due to their low cost and long cycle life. However, the formation of solid compounds such as M 2 S 2 and M 2 S (M = Na, K) during cycling limits their performance. Here we unveil intermediate-temperature K-Na/S batteries utilizing advanced electrolytes that dissolve all polysulfides and sulfides (K 2 S x , x = 1–8), significantly enhancing reaction kinetics, specific capacity, and energy density. These batteries achieve near-theoretical capacity (1655 mAh g -1 sulfur) at 75 °C with a 1 M sulfur concentration. At a 4 M sulfur concentration, they deliver 830 mAh g -1 at 2 mA cm -2 , retaining 71% capacity after 1000 cycles. This new K-Na/S battery with specific energy of 150-250 Wh kg -1 only employs earth-abundant elements, making it attractive for long-duration energy storage.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Unexpected trends in the enhanced Ce 3+ surface concentration in ceria–zirconia catalyst materials

Despite the immense importance of ceria–zirconia solid solutions in heterogeneous catalysis, and the growing consensus that catalytic activity correlates with the concentration of reduced Ce 3+ species and accompanying oxygen vacancies, the extent of reduction at the surfaces of these materials, where catalysis occurs, is unknown. Using angle-resolved X-ray Absorption Near Edge Spectroscopy (XANES), we quantify under technologically relevant conditions the Ce 3+ concentration in the surface (2–3 nm) and bulk regions of ceria–zirconia films grown on single crystal yttria-stabilized zirconia, YSZ (001). In all circumstances, we observe substantial Ce 3+ enrichment at the surface relative to the bulk. Surprisingly, the degree of enhancement is highest in the absence of Zr. This behavior stands in direct contrast to that of the bulk in which the Ce 3+ concentration monotonically increases with increasing Zr content. Overall, these results suggest that while Zr enhances the oxygen storage capacity in ceria, undoped ceria may have higher surface catalytic activity. They further urge caution in the use of bulk properties as surrogate descriptors for surface characteristics and hence catalytic activity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

A General Binary Isotherm Model for Amines Interacting with CO 2 and H 2 O

CO 2 capture by primary or secondary amines has been of great research interests for a century because of its industrial importance. Interest has grown even more, because of the need to eliminate the CO 2 emissions that drive global warming. Experimental evidence shows that CO 2 sorption in primary or secondary amines is accompanied by co-absorption of H 2 O. A quantitative analysis of such CO 2 -H 2 O co-absorption behavior is important for practical process design and theoretical understanding. Even though there is almost an experimental consensus that water enhances CO 2 uptake capacity, an analytic model to explain this phenomenon is not well established. Instead, some empirical models such as the Toth model are used to describe the isotherm without accounting for the presence of water. Recently, we have demonstrated that the isotherm equation of CO 2 sorption into strong-base anion exchange materials with quaternary ammonium can be derived from that of strong-base aqueous alkaline solutions by correcting for the drastic change in water activity and by including an appropriate parameterization of the water activity terms. In this paper, we generalize this model from quaternary ammonium to primary, secondary and tertiary amines either in solutions or as functional groups in polymer resins. For primary, secondary and tertiary amines, the isotherm equation can be derived by extending that of a weak-base aqueous alkaline solution such as aqueous ammonia. The model has been validated using experimental data of aqueous ammonia in literature. Furthermore, this general model even includes quaternary ammonium as a special limit. Hence, this general model offers a platform that can treat the isotherms of solid amines, aqueous amines and aqueous alkaline solutions in a unified way.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

The Upgrade of the SNS Extraction Kicker Power Supplies for the Proton Power Upgrade

The Proton Power Upgrade (PPU) project at the Spallation Neutron Source (SNS) aims to enhance the linear accelerator's power output from 1.4 to 2.8 megawatts. A critical focus lies on upgrading the Extraction Kicker Power Supplies to handle the amplified beam power. The existing capacitor charging power supplies lacked the capability to charge the Blumlein-type Pulse Forming Network (PFN) to the required 40 kV at a repetition rate of 60 Hz. To address this limitation, an initial solution involving the use of a resonant charging circuit was proposed. However, a challenge arose with a self-firing issue in the thyristor switch, which proved unsolvable within the given timeframe. Facing a critical decision point in the project, an alternative approach was explored: integrating a supplementary power supply to enhance the overall power capacity. This solution was tested and ultimately chosen as the path forward. To accommodate the additional power supply, the power distribution system had to undergo upgrades. Throughout this endeavor, a comprehensive examination of the system took place, with meticulous identification of key components. This paper delves into the technical challenges encountered during the process and the corresponding solutions that were implemented.

Tan, Yugang [ORNL] (ORCID:0000000155968252)↗
DOE OSTI2025

Thermal Modeling and Limitations for Power Electronics Embedded in Medium-Voltage Cables

As next-generation energy technologies gain traction and power demand increases, the existing electrical infrastructure faces significant stress, prompting innovative solutions to enhance the grid's capacity and lifespan. This work explores the possibility of embedding medium-voltage (MV) power electronics directly inline with the cable, and the resulting thermal challenges. Since the majority of power distribution cables installed in the U.S. are passively cooled, the work focuses primarily on passive cooling, with an emphasis on the limitations of axial heat spreading within the cable. To date, literature on axial spreading of high incident heat loads on cables and cable environments is limited, typically reporting cases with <10 W of incident heat load. This work will explore the considerations, limits, and tradeoffs of cable-embedded heat loads significantly larger than the cable losses. Both external and internal effects are modeled analytically in nondimensional terms via a Biot number analysis, allowing fundamental limits and tradeoffs to be derived. The work culminates in the design and experimental validation of a cable-embedded thermal system capable of passively dissipating 300 W of heat from a coaxial SiC mosfet switch module over a length of 20 cm, thus validating the possibility of MV cable-embedded power electronics from a thermal standpoint.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Highly textured metal anodes for stable aqueous batteries: Fabrication and characterization

We report a purely mechanical “cold-compression flow” method for fabricating Zn, Sn, and In substrates with tunable crystallographic textures. Using textured Zn as a model system, we investigate Zn electrocrystallization and demonstrate correlated growth of crystalline films with correlation lengths from tens to hundreds of micrometers. At 5 milliamperes per square centimeter (mA/cm 2 ), capacities between 20 and 82 milliampere hours per square centimeter (mA·hour/cm 2 ) are achieved depending on substrate texture level. At higher currents (40 mA/cm 2 ), capacities reach up to 604 mA·hour/cm 2 . Rotating disk electrode studies show that dominantly (002) textured Zn substrates exhibit enhanced corrosion resistance and reduced interphase passivation. We introduce an effective Damköhler number (Da*) to concisely describe morphological evolution during electrocrystallization across substrates with different textures. High-texture (002) Zn substrates substantially enhance performance in high-capacity (~20 mA·hour/cm 2 ) symmetric Zn||Zn cells and full cells (Zn||δ-MnO 2 and Zn||I 2 ), enabling fast-charging and prolonged energy storage in coin and pouch rechargeable Zn battery formats.

Science & Technology - Other Topics↗