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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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Electrochemically Responsive Self-Formed Li-ion Conductors for High Performance Li Metal Anodes
The project will develop and optimize organo-Li x S y , organo-Li x P y S z , and organo-Li x S y /organo-Li x P y S z composite materials as protective layers for Li metal anodes in Li-S batteries. The core focus will be on synthesis methods and precursors for new organic/inorganic hybrid Li-ion conductors, protective layer composition, and protective layer fabrication methods. This will be accompanied by property measurement and characterization (conductivity, mechanical properties, etc.) for the protective layer on Li metal, as well as detailed diagnostics and cell testing. At the conclusion of the project, twelve ~300 mAh pouch cells will be delivered which use the optimal protection layer.
Static and Dynamic Compression and Deformation Behavior of High-Entropy Transition Metal Borides.
Abstract not provided.
High-Performance Metal-ceramic Hybrid Coatings for Extreme Conditions.
Abstract not provided.
Fabrication of High Aspect Ratio Metallic Pillar Arrays
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The Jupiter Experiments: High-240 Plutonium Metal Plates Separated by Lead and Reflected by Copper
Each layer consisted of a 6 by 6 matrix of either these fuel-filled containers or solid blocks of copper of the same outer dimensions. An example of this arrangement, along with one of the copper inner reflectors, is shown in Figure 1.4. This figure shows the same aluminum containers from Figure 1.3 but with the aluminum containers completely closed. The lifting rings shown on the copper inner reflector were only for assembly and were not present for the measurement (in which the holes were filled with copper plugs). Figure 1.5 shows the loading arrangement of the aluminum containers, along with aluminum shims around the container arrays to ensure a tight fit between these layers and the surrounding reflectors. All plates were in the same orientation; none were rotated in any fashion. Additional loading information for the PAHN plates and plate loading respective to the room entrance are provided in Figures 1.6 and 1.7, respectively.
Active Learning Discovery of High Diffusion Metal-Organic Frameworks for Carbon Dioxide Conversion
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Design of High-Entropy Metal-Organic Frameworks For Effective CO2 Fixation
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High Coulombic efficiency cycling of metal batteries
Embodiments of a method for cycling a rechargeable alkali metal battery with high Coulombic efficiency (CE) are disclosed. A slow charge/rapid discharge protocol is used in conjunction with a concentrated electrolyte to achieve high CE in rechargeable lithium and sodium batteries, include anode-free batteries. In some examples, the CE is ≥99.8%.
Phononic Barrier Communication: Channeling Information and Energy through Metallic Barriers with High Fidelity High Efficiency and Low Bit Errors.
Abstract not provided.
High-Performance Metal-ceramic Hybrid Coatings for Extreme Conditions.
Abstract not provided.
Salt-rich solid electrolyte interphase for safer high-energy-density Li metal batteries with limited Li excess
We propose a carbonate-based electrolyte optimized with dual cations and ionic liquid for high-efficiency Li metal batteries with a high-voltage cathode. An average coulombic efficiency of Li deposition of 99.6% is achieved due to the salt-rich solid electrolyte interphase and Na guided uniform Li plating. The Li||NCM811 cells can be cycled with limited Li (N/P = 1) over 90 cycles. An additional advantage is that it improves the thermal stability of the NCM811 cathode.
Environment of Metal–O–Fe Bonds Enabling High Activity in CO 2 Reduction on Single Metal Atoms and on Supported Nanoparticles
Single-atom catalysts are often reported to have catalytic properties that surpass those of nanoparticles, while a direct comparison of sites common and different for both is lacking. In this work, we show that single atoms of the Pt-group embedded into the surface of Fe 3 O 4 have a greatly enhanced interaction strength with CO 2 compared with Fe 3 O 4 surface. The strong CO 2 adsorption on single Rh atoms and corresponding low activation energies lead to two-orders-of-magnitude higher conversion rates of CO 2 compared to Rh nanoparticles. This high activity of single atoms stems from the partially oxidic state imposed by their coordination to the support. Fe 3 O 4 -supported Rh nanoparticles follow the behavior of single atoms for CO 2 interaction and reduction, which is attributed to the dominating role of partially oxidic sites at the Fe 3 O 4 -Rh interface. Thus, we show a likely common catalytic chemistry for two kinds of materials thought to be different, and we show that single atoms of Pt-group metals on Fe 3 O 4 are an especially successful material for catalyzed reactions that depend primarily upon sites with the metal-O-Fe environment.
Atomic structure of an FeCrMoCBY metallic glass revealed by high energy x-ray diffraction
Amorphous bulk metallic glasses with the composition Fe 48 Cr 15 Mo 14 C 15 B 6 Y 2 have been of interest due to their special mechanical and electronic properties, including corrosion resistance, high yield-strength, large elasticity, catalytic performance, and soft ferromagnetism. Here, we apply a reverse Monte Carlo technique to unravel the atomic structure of these glasses. The pair-distribution functions for various atomic pairs are computed based on the high-energy x-ray diffraction data we have taken from an amorphous sample. Monte Carlo cycles are used to move the atomic positions until the model reproduces the experimental pair-distribution function. The resulting fitted model is consistent with our ab initio simulations of the metallic glass. Our study contributes to the understanding of functional properties of Fe-based bulk metallic glasses driven by disorder effects.
Operating High-Energy Lithium-Metal Pouch Cells with Reduced Stack Pressure Through a Rational Lithium-Host Design
Transitioning from a liquid electrolyte to an inorganic solid electrolyte offers a potential pathway to enable highly reversible lithium-metal anodes. However, the solid-electrolyte-protected lithium-metal anode suffers from poor interfacial ionic contacts and requires an impractically high stack pressure (>1.0 MPa) to maintain the interfacial contacts. It is demonstrated here that combining a hollow silver/carbon fiber scaffold and an inorganic/organic composite electrolyte enables a highly reversible lithium-metal anode. Since the high surface area of the electrode provides intimate contact and the hollow structure of the electrode relieves the lithium plating-induced stress, the electrode/electrolyte interface remains stable during cycling even under mild stack pressure. This unconventional structural design is validated in practical pouch cells assembled with the 3D lithium host containing a onefold excess of lithium and a high-nickel cathode. At a mild stack pressure of 320 kPa, the pouch cell displays 83% capacity retention for 200 cycles. This work illustrates that combining a hollow electrode architecture and a robust solid electrolyte offers a practical pathway toward rechargeable lithium-metal anodes.
A Stable Site‐Isolated Mono(phosphine)‐Rhodium Catalyst on a Metal‐Organic Layer for Highly Efficient Hydrogenation Reactions
Abstract Phosphine‐ligated transition metal complexes play a pivotal role in modern catalysis, but our understanding of the impact of ligand counts on the catalysis performance of the metal center is limited. Here we report the synthesis of a low‐coordinate mono(phosphine)‐Rh catalyst on a metal‐organic layer (MOL), P‐MOL • Rh, and its applications in the hydrogenation of mono‐, di‐, and tri‐substituted alkenes as well as aryl nitriles with turnover numbers (TONs) of up to 390000. Mechanistic investigations and density functional theory calculations revealed the lowering of reaction energy barriers by the low steric hindrance of site‐isolated mono(phosphine)‐Rh sites on the MOL to provide superior catalytic activity over homogeneous Rh catalysts. The MOL also prevents catalyst deactivation to enable recycle and reuse of P‐MOL • Rh in catalytic hydrogenation reactions.
Towards controlling the reversibility of anionic redox in transition metal oxides for high-energy Li-ion positive electrodes
Transition metal d-states and oxygen p-states overlap and oxygen lattice integrity dictates the oxygen redox reversibility in metal substituted Li 2 RuO 3 positive electrodes for Li-ion batteries.
Overcoming misconceptions in lithium metal polymer electrolyte batteries
Uncovering the truth of lithium polymer batteries. Lithium metal is the holy grail of anodes due to its 10-fold higher gravimetric capacity than graphite. All-solid-state lithium polymer electrolyte batteries are receiving significant attention due to their increased flexibility compared to inorganic solid-state electrolytes, which enhances processability, accommodates cell swelling, and enables more homogeneous interphases. However, prototype solid-state lithium polymer electrolyte batteries have been limited in their usage due to the low ionic conductivity of the electrolyte, which limits their ability to cycle lithium metal at high rates. In this opinion, we provide alternative interpretations of high-rate capability lithium metal polymer electrolytes and breakthroughs in highly ionically conductive all-solid-state polymer electrolytes. In addition, we provide guidance on how to characterize and evaluate polymer electrolytes in lithium metal batteries.