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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Depolymerization of Vinyl Polymers

Depolymerization is a promising approach to reduce plastic waste by regenerating monomers from polymers, presenting a compelling solution to maintain a circular polymer economy. However, vinyl polymers with all-carbon backbones are especially difficult to depolymerize due to significant thermodynamic and kinetic barriers. Developments in reversible-deactivation radical polymerization and catalytic methods demonstrate how tuning polymer structure and reaction conditions can address these challenges. This Viewpoint revisits early studies on radical depolymerization and recent advances enabling monomer recovery at lower temperatures. Exciting current trends to utilize depolymerization as a strategy for tuning polymer material properties and upcycling waste polymer to high-value products are discussed. Finally, we outline key directions to make vinyl polymer depolymerization scalable, efficient, and economically viable.

depolymerization↗
DOE OSTI2026

Enhancing Room-Temperature Hydrogen Storage Properties in Ti–V–Cr–Nb–Mo/Fe Multielement Alloys via Substitutional Tuning

Building upon previously reported high-entropy alloys (HEA) in the Ti−V−Cr−Nb−Mo/Fe compositional space, this study presents a novel bcc alloy containing 6 at. % of the earthabundant element Fe, exhibiting enhanced hydrogen storage properties at room temperature (25 °C). The optimized bcc Ti 23 V 30 Nb 10 Cr 31 Fe 6 alloy rapidly absorbs hydrogen at room temperature with a maximum gravimetric capacity of 3.4 wt % and an enthalpy of hydride formation of −34 kJ/mol H 2 . This value is among the lowest reported to date for bcc HEAs. The reversible capacity of this alloy remains stable at 2.0 wt % upon 20 absorption/desorption cycles at room temperature, which is among the highest reported values for this material class. Collectively, these advances highlight the potential of Fecontaining multielement alloys as efficient and economical candidates for next-generation hydrogen storage systems.

08 HYDROGEN↗
DOE OSTI2021

Increasing Iridium Oxide Activity for the Oxygen Evolution Reaction with Hafnium Modification

Synthesis and implementation of highly active, stable, and affordable electrocatalysts for the oxygen evolution reaction (OER) is a major challenge in developing energy efficient and economically viable energy conversion devices such as electrolyzers, rechargeable metal-air batteries, and regenerative fuel cells. The current benchmark electrocatalyst for OER is based on iridium oxide (IrO x ) due to its superior performance and excellent stability. However, large scale applications using IrO x are impractical due to its low abundance and high cost. In this work, we report a highly active hafnium-modified iridium oxide (IrHf x O y ) electrocatalyst for OER. The IrHf x O y electrocatalyst demonstrated ten times higher activity in alkaline conditions (pH = 11) and four times higher activity in acid conditions (pH = 1) than a IrO x electrocatalyst. The highest intrinsic mass activity of the IrHf x O y catalyst in acid conditions was calculated as 6950 A gIrO x -1 at an overpotential (η) of 0.3 V. Combined studies utilizing operando surface enhanced Raman spectroscopy (SERS) and DFT calculations revealed that the active sites for OER are the Ir-O species for both IrO x and IrHf x O y catalysts. The presence of Hf sites leads to more negative charge states on nearby O sites, and shortening the bond lengths of Ir-O, and lowering free energies for OER intermediates to accelerate the OER process.

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

Ammonia Synthesis under Ambient Conditions: Insights into Water–Nitrogen–Magnetite Interfaces

New routes for transforming nitrogen into ammonia at ambient conditions would be a milestone toward an energy efficient and economically attractive production route in comparison to the traditional Haber-Bosch process. Recently, the synthesis of ammonia from water and nitrogen at room temperature and atmospheric pressure has been reported to be catalyzed by Fe 3 O 4 at the air-water interface. By integrating ambient pressure X-ray photoelectron spectroscopy and ab initio molecular dynamics and free energy calculations, we investigate the underlying thermodynamic mechanisms governing ammonia and hydrazine formation at the water-Fe 3 O 4 -nanoparticle interface. Here, we find that, unlike pure Fe 3 O 4 where N 2 can only interact with a limited number of Fe sites, hydroxylated species introduce large and diverse adsorption geometries where N 2 can bind through either Fe sites or Fe-OH groups, each of which are capable of independently facilitating proton-coupled electron transfer.

Chandy, Sruthy K. [University of California, Berke↗
DOE OSTI2025

Optoelectronic polymer memristors with dynamic control for power-efficient in-sensor edge computing

Abstract As the demand for edge platforms in artificial intelligence increases, including mobile devices and security applications, the surge in data influx into edge devices often triggers interference and suboptimal decision-making. There is a pressing need for solutions emphasizing low power consumption and cost-effectiveness. In-sensor computing systems employing memristors face challenges in optimizing energy efficiency and streamlining manufacturing due to the necessity for multiple physical processing components. Here, we introduce low-power organic optoelectronic memristors with synergistic optical and mV-level electrical tunable operation for a dynamic “control-on-demand” architecture. Integrating signal sensing, featuring, and processing within the same memristors enables the realization of each in-sensor analogue reservoir computing module, and minimizes circuit integration complexity. The system achieves 97.15% fingerprint recognition accuracy while maintaining a minimal reservoir size and ultra-low energy consumption. Furthermore, we leverage wafer-scale solution techniques and flexible substrates for optimal memristor fabrication. By centralizing core functionalities on the same in-sensor platform, we propose a resilient and adaptable framework for energy-efficient and economical edge computing.

Optics↗
DOE OSTI2025

Recent advances in enzyme engineering for improved deconstruction of poly(ethylene terephthalate) (PET) plastics

In the last ~20 years, a multitude of natural enzymes have been discovered that can catalyze the breakdown of the common plastic poly(ethylene terephthalate) (PET). While enzymatic PET recycling is an attractive alternative end-of-life route for this waste plastic, the enzymes are not yet optimized for efficient and economical industrial use. Here, we discuss recent advances in engineering these PET-degrading enzymes, which include PET, bis(2-hydroxyethyl) terephthalate (BHET), and 2-hydroxyethyl terephthalic acid (MHET) hydrolases, toward industrially-relevant engineering goals. We place emphasis on trends from past efforts in rational and semi-rational design and emerging areas in directed evolution/high throughput screening and computational design for engineering these enzymes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Predicting Thermochemical Equilibria with Interacting Defects: Sr 1 − x Ce x Mn O 3 − δ Alloys for Water Splitting

Solar thermochemical hydrogen is one of the few potential routes towards direct fuel production from renewable energy sources, but the thermodynamic boundary conditions for efficient and economic energy conversion are challenging. Success or failure of a given oxide working material depends on the subtle balance between enthalpy and entropy contributions in the redox processes. Developing a mechanistic understanding of the behavior of materials on the basis of atomistic models and first-principles calculations is an important part of advancing the technology. One challenge is to quantitatively predict thermochemical equilibria at high concentrations when the redox-active defects start to interact with each other, thereby impeding the formation of additional defects. This problem is of more general importance to applications that rely on high levels of off-stoichiometry or doping, including, for example, batteries, thermoelectrics, and ceramic fuel cells. To account for such repulsive defect interactions, we introduce a statistical mechanics approach, defining an expression for the free energy of defect interaction based on limited sampling of defect configurations in density functional theory supercell calculations. The parameterization of this energy contribution as a function of defect concentration and temperature allows on-the-fly simulation of thermochemical equilibria. The approach consistently incorporates finite temperature effects by including the leading contributions to the temperature-dependent free energy for the case at hand, i.e., the ideal gas and configurational enthalpies and entropies. We demonstrate the capability and utility of the approach by simulating the water splitting redox processes for Sr 1 − x Ce x Mn O 3 − δ alloys. Published by the American Physical Society 2024

08 HYDROGEN↗
DOE OSTI2024

REBCO Insert Coils toward High-Field, Large-Bore Magnet for Quantum Physics Research

High-temperature superconducting (HTS) magnets offer a promising solution for generating high magnetic fields efficiently and economically, serving as a vital component in nextgeneration scientific instruments and carbon-neutral power systems, notably in cost-effective compact fusion reactors. These high magnetic fields play a pivotal role in advancing research on quantum materials, particularly in elucidating the intricate electronic states near magnetic phase transitions. Here, this paper delves into the research conducted at the Princeton Plasma Physics Laboratory, which is divided into three phases aimed at overcoming technical hurdles in creating large-bore, high-field HTS magnets for cutting-edge quantum physics research. In Phase 1, we designed, constructed, and tested a compact REBCO solenoidal magnet comprising six double-pancake coils featuring a 41.3-mm inner diameter and a 70.0-mm outer diameter. It adopts a no-insulation approach to ensure electrical and thermal stability. Successful testing in a saturated liquid nitrogen bath confirmed its capability to generate a 0.8-T field at 77 K and 2 T at 65 K, with ongoing integration into liquid helium testing. Building on this experience, Phase 2 involves the design of an HTS insert coil, intended to nest within a 12-T low-temperature superconducting (LTS) outsert to achieve a minimum of 20 T at 4.2 K. The focus of Phase 2 centers on addressing challenges posed by screening-current (SC) effects, particularly the associated stress/strain issues. Employing a numerical model that fully couples the SC and mechanical analysis, we discuss strategies for managing stress to mitigate the effects of SCinduced stress concentrations.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Leveraging National Laboratory Assets to Address Stability Challenges due to Declining Grid Inertia Using Geographically Distributed Electrical–Thermal Co-Emulation

Due to increased penetration of low-inertia resources into the electric grid, challenges are increasing for maintaining wide-area system stability. Grid stability assessment requires a faithful representation of the multiple-physics interaction at the system level, and timescales of interaction varying in orders of magnitude, from microseconds to seconds to several minutes. Along with the simulation-based techniques, hardware-in-the-loop (HIL), controller HIL, and power HIL techniques have been developed to better understand the emergent behavior of the system with emerging technologies. US National Laboratories have played a vital role in research and development to understand the behavior of individual technologies and devices integrated to the electric grid. Each national laboratory forwards a technological and strategic initiative tied core and enabling capabilities. Due to strategic, efficiency, and economic reasons, not all the labs have assets to conduct research on all technologies concomitantly, so it becomes crucial to integrate the labs across geographies to understand the interplay of different technologies together at the system level. This approach avoids duplication of the assets at different lab facilities and helps understand the integrated system behavior of various technologies representative of actual grid conditions by connecting multiple national labs. This article talks about techniques of connecting three national laboratories to enable co-emulation of electrical–mechanical–thermal characteristics of devices and systems. Such an approach can be used to understand the dynamic and transient interaction of multi-physics in a system level, at-scale emulation using real-time simulation tools and techniques.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2020

Modular RivGen LCOE Content Model

The Modular RivGen LCOE Content Model contains estimates of levelized cost of energy (LCOE) for three array configurations operating in a theoretical river environment. The LCOE is distinguished by the CapEx, OpEx, and annual energy production and capture for each river environment.

16 TIDAL AND WAVE POWER↗
DOE OSTI2023

Autonomous Fracture Conductivity Using Expandable Proppants in Enhanced Geothermal Systems

Summary Early thermal breakthrough in enhanced geothermal systems (EGS) due to the presence of preferential flow channels is a major challenge that endangers efficient and economic heat extraction in such systems. Previous studies mainly focused on adjusting circulation rates of the working fluid, which still leaves significant amounts of untapped heat behind. Currently, there is a lack of technologies for altering flow distribution within the fracture network to achieve uniform heat sweeping in the reservoir. This work presents a novel concept for making proppants to autonomously control fracture conductivity based on the surrounding temperature. Here, proppants with negative thermal expansion coefficients have demonstrated the capability for appropriate fracture conductivity adjustment as a function of temperature to achieve uniform flow across the fracture network. Particle-particle interactions governing such functions are explicitly modeled, and then the Lattice Boltzmann methods (LBM) is used to determine the potential impact of closure stress and temperature changes on the permeability of the proposed proppant packs. Microscale analyses are further used to determine the required material properties to achieve a certain improvement in the permeability of the proppant pack. Our analyses show an enhancement in permeability and the associated fracture conductivity by half of their initial values. Field-scale analysis further confirms the effectiveness of the proposed concept as 31.4% more heat can be extracted from EGS over 50 years of production when the proposed proppants are used. Such novel proppants may effectively delay thermal breakthrough, sweep heat from larger rock volumes, and elongate the life span of the EGS project.

Engineering↗
DOE OSTI2020

Functional Lithography for Advanced Additive Manufacturing

The viability of 3D printing as a manufacturing technology is limited by the material properties of the printed parts. polySpectra successfully developed a scalable, efficient, and economic print process using commercially available hardware in order to 3D print production parts using novel functional lithography resins. The printed parts exhibited unmatched physical and chemical properties. The combination of the novel resin with unique properties and a facile, economic print process will help elevate additive manufacturing from a prototyping tool to a viable manufacturing technology.

42 ENGINEERING↗
DOE OSTI2020

Heat Integration Optimization and Dynamic Modeling Investigation for Advancing the Coal-Direct Chemical Looping Process

The purpose of the project is to address the optimization and startup operation of a modular coal direct chemical looping (CDCL) combustion system integrated with a steam cycle for power generation to reduce the risks involved in further scale-up of the technology. The modular reactor design of the CDCL process provides flexibility in the fabrication of the reactor and in its operating capacity (i.e. turndown ratio) at the cost of a more complex heat exchange network (HEN) design and integration. To address the technology gaps and advance the efficiency and economic feasibility of the CDCL technology, the project will perform a detailed and comprehensive analysis of the integration of a modular CDCL reactor system and a steam cycle system under both static and transient conditions via HEN process performance simulations and system dynamic modeling, respectively. The scope of work consists of 1) Experimental and computational studies of the CDCL combustor reactor 2) Comprehensive static (i.e. steady-state) system HEN design analysis in CDCL 550 MWe commercial unit for power generation and 3) Dynamic modeling of site specific design of 10MWe CDCL large pilot plant. The project team has successfully developed and validated a kinetic model for the oxidation of oxygen carriers in the combustor using the unreacted shrinking core model (UCSM). The model is capable of capturing the oxidation kinetics of fully or partially reduced oxygen carrier particles. A computational fluid dynamics (CFD) model is developed to simulate the hydrodynamics, heat transfer, and chemical reaction occurring in the CDCL combustor. The model is developed in MFIX and ANSYS Fluent. Key aspects of CDCL combustor operation, including heat transfer, oxygen carrier oxidation, and the transport of oxygen carrier particles, are simulated using this CFD model. The HEN for a commercial scale 550 MWe CDCL power plant is simulated and optimized using ASPEN Plus. Practical design considerations are incorporated based on industrial experiences. The performance and cost for the commercial CDCL plant is updated based on these analyses. A dynamic model for the 10 MWe CDCL pilot plant is developed in ProTRAX simulation software. The model is based on the pilot plant design developed in project DE-FE0027654 “10 MWe CDCL Large Pilot Plang – Pre-FEED Study” and the steam cycle data obtained from Dover Light & Power plant. The transient behaviors during pilot plant load variation are simulated using the dynamic model.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2021

FWP FEW0223: "Advanced Manufactured Carbonate Materials for Algal Biomass Production: Joint LLNL SNL Program" (Final Report)

The ability to easily and cheaply transport carbon dioxide (CO 2 ) from coal-fired power plants equipped with capture facilities to multiple, potentially distant utilization sites of widely varying scales will enable wider use of CO 2 captured from flue gas. In the case of algal biomass cultivation, delivery of CO 2 in the form of carbonate-based materials may provide a more efficient and economical method of inorganic carbon delivery than CO 2 sparging, reducing the cost of algae cultivation and increasing the value of carbon capture. Lawrence Livermore National Laboratory (LLNL) has developed advanced manufactured materials that are well-suited for carbon capture, storage, transport, and delivery. These materials consist of aqueous sodium carbonate, which captures CO 2 as sodium bicarbonate, extruded or 3D printed in a CO 2 permeable polymer to increase the surface area and improve capture kinetics. By encapsulating carbonate solutions, LLNL has demonstrated order-of-magnitude enhancements in carbon capture rates compared with liquid carbonates, enabling the use of these (otherwise kinetically-limited) inexpensive, environmentally-benign solvents for carbon capture.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2021

Microstructural Model for Creep-Fatigue Interaction in Grade 91 Steel

This report describes the completion of a crystal plasticity finite element simulation framework for creep-fatigue deformation and damage in Grade 91 steel. In addition to a description of the framework and a set of verification calculations, the report details an initial set of simulations applying the framework to examine low cycle fatigue and creep-fatigue interaction in Grade 91 at 600° C. Grade 91 is a likely material for future advanced microreactors and creep-fatigue will be a limiting structural damage mechanism, particularly for mobile reactors or load following systems. The framework described here could provide a better understanding of creep-fatigue damage mechanisms and directly examine creep, fatigue, and creep-fatigue interaction for Grade 91 at realistic component service conditions. This in turn could lead to improved design methods and component life estimation approaches, leading to more efficient and economical component designs.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Herbaceous Feedstock 2020 (State of Technology Report)

The Energy Independence and Security Act (EISA) of 2007 required a minimum supply of 36 million gallons of renewable fuels per year by 2022. In order to achieve these goals, the Bioenergy Technologies Office (BETO) has set cost and technology targets for producing advanced and cellulosic biofuels. One of the targets is to validate feedstock supply infrastructures and systems with 90% overall operating effectiveness and field-to-reactor throat delivered cost less than $85.51/dry ton (2016). As stated by the 2017 Multi-Year Program Plan (DOE 2017), the research and development focus of the Feedstock Technologies (FT) platform is reducing the cost, improving the supply chain logistic efficiency, improving biomass quality, and increasing the supply volume. In addition, BETO oversees annual State of Technology (SOT) report that assesses current technologies that are relevant to BETO’s targets based on actual data and experimental results. Feedstocks are essential to achieving BETO goals because the cost, quality, and quantity of feedstock available and accessible at any given time limit the maximum volume of biofuels that can be produced. In accordance with the 2016 Multi-Year Program Plan (DOE 2016a), FT focuses on (1) reducing the delivered cost of sustainably produced biomass, (2) preserving and improving the physical and chemical quality parameters of harvested biomass to meet the individual needs of biorefineries and other biomass users, and (3) expanding the quantity of feedstock materials accessible to the bioenergy industry. This is done by identifying, developing, demonstrating, and validating efficient and economical integrated systems for harvest and collection, storage, handling, transport, and preprocessing raw biomass from a variety of crops to reliably deliver the required supplies of high-quality, affordable feedstocks to biorefineries as the industry expands. The elements of cost, quality, and quantity are key considerations when developing advanced feedstock supply concepts and systems (DOE 2016a).

09 BIOMASS FUELS↗
DOE OSTI2022

Versatile Heat Transfer Module

Development of micro-reactors that can be easily transported to remote areas for civilian or military applications is an immediate focus of U.S. nuclear industry and therefore is being pursued by multiple reactor vendors (e.g. HolosGen LLC, Westinghouse, Ultra Safe Nuclear Corporation, URENCO, etc.) and actively supported by DOE-NE, DOE-ARPA-E and by the Department Of Defense (DoD). Very-high-temperature gas-cooled (VHTR) and heat pipe cooled reactor technologies are regarded as promising concepts for microreactors applications since they enable compact power conversion systems and display beneficial inherent safety features. Development of microreactors with enhanced performance must be supported by innovations in nuclear technologies. Several technologies being developed by the microreactor industry are being revisited with material technologies developed at the Argonne National Laboratory (ANL). Innovative high-temperature compatible solutions are developed to enable advanced thermal-spectrum microreactor designs featuring improved neutronics performance at high-temperature operating conditions to enable high thermal efficiency and economic competitiveness. This report focuses on the Versatile Heat Transfer Module (VHTM) technology that is developed at ANL for heat-transfer in thermal-spectrum microreactors. This technology is built on a liquid alkali metal heat pipe concept while leveraging advanced nuclear material technologies for high-temperature applications at reduced neutronic penalty with potential improvement in inherent safety behavior. The VHTM can be applied to design high-temperature thermal-spectrum microreactor systems with reduced size, weight, uranium enrichment, or increased lifetime. The INFINIT technology deriving from the VHTM enables design of a highly compact long-life microreactor concept for fission surface power (FSP). Demonstration of multiphysics modeling capability was also completed to showcase the added inherent safety benefits obtained with this concept. The VHTM technology remain at an early development stage with low Technology Readiness Level and Manufacturing Readiness Level. The current demonstration of these technologies has focused on manufacturing capability, on performance of the hydrogen diffusion barrier under thermal cycling, while radiation tolerance demonstration is planned. The next step of the demonstration plan will be the assembly of miniature VHTM for high-temperature testing, which can be used as a prototype for future pilot scale demonstration. Such research is critical to pursue development of these technologies that have the clear potential to significantly improve the performance of currently investigated micro-reactors systems.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗