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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 1,243 records · Page 69
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Synthesis and characterization of polylactic acid microspheres via emulsion-based processing

Polylactic acid (PLA) microspheres are primarily used in drug delivery applications and rarely manufactured commercially. In encapsulation, the drug encapsulation and microsphere synthesis process happen simultaneously. Simultaneous synthesis necessitates conditions that ensure the drugs to be encapsulated remain viable in the synthesis process. Here, in the present work, solid pure PLA microspheres are prepared using a repeatable centrifugal mixing method to create a single emulsion system. A planetary thinky mixer is used to achieve centrifugal mixing. PLA acts as the dispersed phase of the emulsion, whereas Polyvinyl alcohol (emulsifier) dissolved in deionized water serves as the bulk phase. The emulsions are stirred for about 4 min at 2000 rpm. Microspheres prepared by mechanical mixing are compared with microspheres prepared by centrifugal mixing. The microspheres prepared by centrifugal mixing proved to be narrower and closer to a normal distribution with a mean size (D x 50) of 30 microns. The size distribution of planetary mixed microspheres did not change from one batch to another.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Synthesis and Understanding of Novel Catalysts

The research took advantage of our capabilities to perform in-situ and operando Raman spectroscopy on complex systems along with our developing expertise in the synthesis of uniform, supported metal oxide materials to investigate relationships between the catalytically active oxide composition, atomic structure, and support and the corresponding chemical and catalytic properties. The project was organized into two efforts: 1) Synthesis of novel catalyst materials by atomic layer deposition (ALD). 2) Spectroscopic and chemical investigations of coke formation and catalyst deactivation. ALD synthesis was combined with conventional physical characterization, Raman spectroscopy, and probe molecule chemisorption to study the effect of supported metal oxide composition and atomic structure on acid-base and catalytic properties. Operando Raman spectroscopy studies of olefin polymerization leading to coke formation and catalyst deactivation clarified the mechanism of coke formation by acid catalysts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Synthesis and Exploratory Catalysis of 3d Metals: Group-Transfer Reactions, and the Activation and Functionalization of Small Molecules Including Greenhouse Gases

Our work over the past three years has resulted in the development of electron rich and low-coordinate vanadium fragments, molecular nitrides of vanadium and parent imide systems of titanium, and the synthesis of phosphorus containing molecules of the 3d transition metal series. Likewise, with financial support from BES Division in DOE (DE-FG02-07ER15893), we now completed the full characterization of the first single molecular magnet (SMM) of Fe(III). We demonstrated that this monomeric form of Fe(III) has an unusual slow relaxation of the magnetization under zero applied field. To make matters more interesting, this system also undergoes a rare example of an intermediate to high-spin transition (an S = 3/2 to S = 5/2 transition). In 2010 we reported the synthesis of the first neutral and low-coordinate vanadium complexes having the terminal nitride functionality. We have now completed a full study to understand formation of the nitride ligand from the metastable azide precursor, and have also explored the reactivity of the nitride ligand in the context of incomplete and complete N-atom transfer. During the 2010-2013 period we also discovered a facile approach to assemble low-coordinate and low-valent vanadium(II) complexes and exploit their multielectron chemistry ranging from 1-3 electrons. Consequently, we can now access 3d ligand frameworks such as cyclo-P3 (and its corresponding radical anion), nitride radical anions and cations, low-coordinate vanadium oxo’s, and the first example of a vanadium thionitrosyl complex. A cis-divacant iron(IV) imido having some ligand centered radical has been also discovered, and we are in the process of elucidating its electronic structure (in particular the sign of zero field splitting and the origin of its magnitude), bonding and reactivity. We have also revisited some paramagnetic and classic metallocene compounds with S >1/2 ground states in order to understand their reactivity patterns and electronic structure. Lastly, we are completing the synthesis and characterization of a titanium nitride anion and formation of the first example of boryl and aluminyl imido titanium complexes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Synthesis of a potential fast ionic conductor for Mg 2+ ions

This report represents Powdermet’s attempts to synthesize a novel crystalline solid substance–Mg(B 5 C) 2 . This was expected to exhibit a high Mg 2+ ionic conductivity, exceeding that of all known materials. The project was expected to consist of three major steps: 1) reproduction of a literature synthesis of a rare sodium compound NaB 5 C; 2) substitution of Na+ cations with Mg 2+ cations, resulting in Mg(B 5 C) 2 ; and 3) analysis of its Mg 2+ conductivity. In course of the research, 15 attempts were made to reproduce the literature procedure on synthesis of NaB 5 C, a precursor to the Mg 2+ conductor. The first nine attempts were unsuccessful, but later it was found that NaB 5 C formed when the synthesis was performed in pressurized Ar atmosphere. Powdermet performed partial exchange of Na + to Mg 2+ by heating NaB 5 C with magnesium triflate in sulfolane at 260°C. In another avenue, theoretical optimization of the Mg(B 5 C) 2 structure have been performed with distant goal estimate the activation barrier for the Mg 2+ diffusion and estimate the temperature at which the mobility of Mg 2+ cations will be of the order of 10 -2 S*cm.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Synthesis and Luminescence Characteristics of Cr 3+ doped Y 3 Al 5 O 12 Phosphors

Luminescence performance of yttrium aluminum garnet (Y 3 Al 5 O 12 ) phosphors as a function of Cr 3+ concentration has been investigated via two different wet-chemical synthesis techniques, direct- (DP) and hydrothermal-precipitation (HP). Using either of these methods, the red-emitting phosphor [Y 3 Al 5-x Cr x O 12 (YAG: Cr 3+ )] showed similar photoluminescence (PL) intensities once the dopant concentration was optimized. Specifically, the YAG: Cr 3+ PL emission intensity reached a maximum at Cr 3+ concentrations of x = 0.02 (0.4 at.%) and x = 0.13 (2.6 at.%) for DP and HP processed samples, respectively. The results indicated the strong influence of the processing method on the optimized YAG: Cr 3+ performance, where a more effective energy transfer rate between a pair of Cr 3+ activators at low concentration levels was observed by using the DP synthesis technique. Development of a highly efficient phosphor, using a facile synthesis approach, could significantly benefit consumer and industrial applications by improving the operational efficiency of a wide range of practical devices.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Sustainable Ammonia Synthesis – Exploring the scientific challenges associated with discovering alternative, sustainable processes for ammonia production

Ammonia (NH 3 ) is essential to all life on our planet. Until about 100 years ago, NH 3 produced by reduction of dinitrogen (N 2 ) in air came almost exclusively from bacteria containing the enzyme nitrogenase.. DOE convened a roundtable of experts on February 18, 2016. Participants in the Roundtable discussions concluded that the scientific basis for sustainable processes for ammonia synthesis is currently lacking, and it needs to be enhanced substantially before it can form the foundation for alternative processes. The Roundtable Panel identified an overarching grand challenge and several additional scientific grand challenges and research opportunities: -Discovery of active, selective, scalable, long-lived catalysts for sustainable ammonia synthesis. -Development of relatively low pressure (<10 atm) and relatively low temperature (<200 C) thermal processes. -Integration of knowledge from nature (enzyme catalysis), molecular/homogeneous and heterogeneous catalysis. -Development of electrochemical and photochemical routes for N 2 reduction based on proton and electron transfer -Development of biochemical routes to N 2 reduction -Development of chemical looping (solar thermochemical) approaches -Identification of descriptors of catalytic activity using a combination of theory and experiments -Characterization of surface adsorbates and catalyst structures (chemical, physical and electronic) under conditions relevant to ammonia synthesis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Synthesis of SHAL and SHAL Precursor Standard, CRADA No. TC02174.0

The purpose of this CRADA was to establish a collaborative effort between SHAL Technologies and Lawrence Livermore National Laboratory that would advance the development and testing of a family of small molecule oncology drugs and companion diagnostics called selective high affinity ligands (SHALs) for the treatment of advanced non-Hodgkin’s lymphoma. These compounds were first synthesized by the LLNL chemist participating in this CRADA when the compounds were first developed (2004-2008) by the founders of SHAL Technologies (while they were employed at LLNL). This CRADA initially had five deliverables. Deliverables 1-3 involved LLNL’s synthesis of 10-50 mg of the SHALs SH7133 and SH7139 using the same bench-scale conditions used previously, their purification, and obtaining data needed to demonstrate the mass and purity of the compounds. Deliverable 4, which was to be completed by SHAL Technologies, was the comparison of the bench-scale synthetic products to the same compounds manufactured on the multigram to kilogram scale by the contract research organization (CRO) AmbioPharm Inc. The fifth deliverable was this final report. An amendment was made to add the additional tasks and deliverables needed to synthesize the third SHAL standard SH7129 (the diagnostic) and compare it to product manufactured by AmbioPharm. During the testing of the three standards synthesized by LLNL, the SHAL compounds were found to lack biological activity. When we discovered that a commercial chemical supplier provided both LLNL and our CRO AmbioPharm with a SHAL precursor that had the wrong structure, two amendments to the CRADA were made to add additional tasks and deliverables to enable us to repeat all the syntheses and conduct more extensive testing of the bench scale and manufactured products. Once the final correct products were synthesized and confirmed to have the right structures, a third amendment was added to the CRADA to enable the synthesis of two fragments of the SHALs to determine if these compounds are produced when the SHALs are metabolized. This last synthesis was included to provide the information needed to establish a second, new CRADA between SHAL Technologies and LLNL that would focus on the identifying how the SHALs are metabolized and how their metabolic products may be responsible for the selective killing of tumor cells over-expressing the protein targeted by the SHALs, HLA-DR10.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Final Report: Archiving Data to Support Data Synthesis of DOE Sponsored Elevated CO 2 Experiments

Over the last three decades DOE made a large investment in field-scale experiments in order to understand the role of terrestrial ecosystems in the global carbon cycle, and forecast how carbon cycling will change over the next century. The Smithsonian Environmental Research Center received one of the first awards in this program and managed two long-term studies (25 years and 10 years) with a total of approximately $10 million of support from DOE, and many more millions leveraged from the Smithsonian Institution and agencies such as NSF. The present DOE grant was based on the premise that such a large investment demands a proper synthesis effort so that the full potential of these experiments are realized through data analysis and modeling. The goal of the this grant was to archive legacy data from two major elevated carbon dioxide experiments in DOE databases, and to engage in synthesis activities using these data. Both goals were met. All datasets deemed a high priority for data synthesis and modeling were prepared for archiving and analysis. Many of these datasets were deposited in DOE’s CDIAC, while others are being held at the Oak Ridge National Lab and the Smithsonian Institution until they can be received by DOE’s new ESS-DIVE system at Berkeley Lab. Most of the effort was invested in researching and re-constituting high-quality data sets from a 30-year elevated CO 2 experiment. Using these data, the grant produced products that are already benefiting climate change science, including the publication of new coastal wetland allometry equations based on 9,771 observations, public posting of dozens of datasets, metadata and supporting codes from long-term experiments at the Global Change Research Wetland, and publication of two synthetic data papers on scrub oak forest responses to elevated CO 2 . In addition, three papers are in review or nearing submission reporting unexpected long-term patterns in ecosystem responses to elevated CO 2 and nitrogen in a coastal wetland.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Synthesis of a Novel Energetic Heterocyclic Oxidizer with Higher Energy and Lower Sensitivity Final Report CRADA No. TC02099.0

The project involved the synthesis of 5g of a target energetic compound, 3,4-bis(5-nitro-1,2,5- oxadiazol-4-yl)-1,2,5-oxadiazole-1-oxide (DNTF. The deliverables were the synthesis of 5g of DNTF along with quantities of the precursor compounds. In addition, small-scale safety tests on DNTF were performed, which to confirmed that DNTF has no undesirable safety properties before scaling up the synthesis in Phase II of this project.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Bioinspired synthesis and self-assembly of hybrid organic–inorganic nanomaterials

Nature is replete with complex organic–inorganic hierarchical materials of diverse yet specific functions. These materials are intricately designed under physiological conditions through biomineralization and biological self-assembly processes. Tremendous efforts have been devoted to investigating mechanisms of such biomineralization and biological self-assembly processes as well as gaining inspiration to develop biomimetic methods for synthesis and self-assembly of functional nanomaterials. In this work, we focus on the bioinspired synthesis and self-assembly of functional inorganic nanomaterials templated by specialized macromolecules including proteins, DNA and polymers. The in vitro biomineralization process of the magnetite biomineralizing protein Mms6 has been investigated using small-angle X-ray scattering. Templated by Mms6, complex magnetic nanomaterials can be synthesized on surfaces and in the bulk. DNA and synthetic polymers have been exploited to construct macroscopic two- and three-dimensional (2D and 3D) superlattices of gold nanocrystals. Employing X-ray scattering and spectroscopy techniques, the self-assembled structures and the self-assembly mechanisms have been studied, and theoretical models have been developed. Our results show that specialized macromolecules including proteins, DNA and polymers act as effective templates for synthesis and self-assembly of nanomaterials. These bottom-up approaches provide promising routes to fabricate hybrid organic–inorganic nanomaterials with rationally designed hierarchical structures, targeting specific functions.

36 MATERIALS SCIENCE↗
DOE OSTI2020

iClick Synthesis of Metallopolymers and Highly Emissive Materials

This project involves the exploitation of iClick (Inorganic Click) to link two or more metal ions. The novel cycloaddition between a metal-azide and a metal-acetylide developed at UF provides an opportunity to prepare materials that were previously unimaginable. Further developing the synthetic methodology of iClick will open new frontiers for materials synthesis. Three specific goals are outlined in the project: 1) investigate the chemistry of iClick and its application to linking metal ions, 2) develop a method to dynamically tune the emission color of soluble gold-oligomers, and 3) exploit iClick synthesis to develop new conjugated Pt- and Ru-metallopolymers. Metallopolymers are on the cusp of revolutionizing the energy sector, information storage, and materials synthesis. Uniquely, transition metal chemistry marries polymer science in these hybrid materials wherein the metal ion imparts new properties unimaginable for organic polymers alone.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Renewable Solvents to Replace Water in the Synthesis of Battery Materials

Our lab has been engaged in using glycerol to replace water in the synthesis of metal oxides, especially those for use in Li-ion battery. Glycerol is a byproduct from biodiesel production. The U.S. biodiesel manufacturers generate about 1 billion pounds of glycerol yearly, which needs to be utilized for producing value added products. By using glycerol as a solvent, we found that it can replace water to prepare many metal oxide powders. The materials synthesis processes have the potential to significantly reduce manufacturing cost and alleviate the environmental issues with aqueous processes. In this talk, I will present some of our work in materials synthesis using glycerol as a solvent. In particular, I will introduce the work on making active cathode materials for the Li-ion battery.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Understanding the cold plasma synthesis of ammonia with model metal catalysts through plasma diagnostics (Final Report)

The industrial synthesis of ammonia, which amounts to over 200 million tons annually, is the most energy-intensive chemical process. Therefore, there is a critical need and increased interest in exploring less energetic routes to produce ammonia. Not only does ammonia have a direct impact on the food market, but also it has the potential as a fuel and hydrogen carrier. Recently, plasma catalysis has emerged as a promising alternative for synthesizing ammonia at mild (pressure, temperature and power) conditions. The key to this catalytic process is the synergy between the plasma and the catalyst, where the non-equilibrium plasma allows the generation of excited species, which recombine at the catalyst surface to form ammonia. However, our current understanding of this process is in its infancy. In this respect, model metals are ideal candidates for gaining a basic understanding of this reaction. Moreover, a major roadblock to rationally designing novel effective catalysts for plasma-assisted ammonia production is the need for fundamental aspects of this process. Through a comprehensive plan that integrates model metals as catalysts and world-class diagnostics, the proposed work aims to provide fundamental knowledge about the nature of reactive processes occurring during plasma-assisted catalysis and to demonstrate the selective production of ammonia, catalyzed by employing selected metals under non-thermal plasma conditions. Toward this goal, the central thrust of this proposal was to demonstrate that the synergy between plasma and rationally selected model metals will boost ammonia yields during plasma-assisted ammonia synthesis by delaying hydrogen recombination. Specifically, we aimed to (1) understand the formation and role of gas-phase active species such as NH, N 2 , N 2 + and Ha during the plasma-enhanced synthesis of ammonia through OES and FTIRAS using different reaction configurations: a) only plasma (non-packed DBD reactor) and b) packed DBD reactor with metal nanoparticles. This proposal was awarded/recommended with a run time on the PCRF facility FY20.

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

Thermodynamic controls on the synthesis, structure and reactivity of materials for energy (Final Report)

The major objectives of this renewal proposal, now entitled “Thermodynamic Controls on the Synthesis, Structure and Reactivity of Materials for Energy,” are: (a) to advance and use unique calorimetric capabilities to determine the energetics of materials relevant to energy applications, with an emphasis on new materials, (b) to understand, in terms of both macroscopic energetics and microscopic structure and bonding, the interplay of defect chemistry, oxidation-reduction and size effects at the nanoscale in determining the properties of functional oxide materials and of new classes of non-oxide materials. Recent developments have generated great excitement in organic-inorganic hybrid materials such as the alkylammonium lead halide perovskites. Our current work has emphasized fluorite-based solid electrolytes, perovskites and lithium battery materials. The systematic trends seen enable a more holistic view of the relation of thermodynamics to materials discovery and synthesis. The proposed work more explicitly targets thermodynamic controls on metastability, energy landscapes, surface and nanoscale effects, and pathways of synthesis and decomposition. This project is leveraged by many U.S. and international collaborations that both extend the science and provide opportunities for work in a diverse global setting.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Technical and Economic Assessment and Gap Analysis of Advanced Nuclear Reactor Integration with a Reference Methanol Synthesis Plant

Efforts continue to identify the most-economic methods to decarbonize several sectors of the United States (U.S.) economy. Industrial processes such as synfuel synthesis and high value commodity chemicals rely heavily on energy-dense and easily stored and transported fossil fuels, which power and feed their operations. Steam methane reforming (SMR) is a widely used process for producing methanol. In this process, methane (CH 4 ) from natural gas (NG) reacts with steam (H 2 O) over a catalyst at high temperatures (700-1,000°C) to produce syngas, a mixture of hydrogen (H 2 ) and carbon monoxide (CO). The syngas is then converted into methanol (CH 3 OH) through a second catalytic reaction. This method is known for being an efficient and commonly employed pathway for industrial methanol production. The high-temperature heat needed for SMR, which is currently used in the natural-gas-to-methanol process, cannot be supplied by small modular nuclear reactor (SMNR) direct heating; the temperatures required for the SMR process exceed those of the main steam produced by near-market high-temperature gas reactors (HTGRs). For the conventional methanol process, this leaves possible nuclear-integration opportunities that include: (1) blending nuclear hydrogen into the SMR NG fuel, or (2) assessing alternative synthesis routes leveraging nuclear capabilities and steam electrolysis outputs. In the reference methanol plant, SMR provides the methanol-synthesis reactor with H 2 and co. In Case (2), the state-of-the-art reverse water gas shift (RWGS) pathway achieves the same, sourcing carbon from an industrial CO 2 source.

08 HYDROGEN↗
DOE OSTI2019

Synthesis of Plutonium Oxide Specimens for a Statistically Designed Nuclear Forensics Study

This report describes the synthesis of plutonium oxide (PuO 2 ) samples at a bench-scale (10 g Pu) to support nuclear forensics research. The key unit operations that were performed included dissolving the PuO 2 feed material, purifying the Pu by ion exchange, precipitating as plutonium (III) oxalate, and reconverting to PuO 2 by calcination of the oxalate compound. Seventy-six PuO 2 synthetic runs were performed in execution of a statistically designed test matrix. The process parameters varied in these synthesis runs included temperature (30 or 50 °C), the Pu concentration in the feed solution (10, 30, or 50 g Pu/L), the HNO 3 concentration in the feed solution (1, 2, or 3 M), the direction of reagent addition (direct or reverse strike), the source of oxalic acid (solid or solution), and the reagent addition rate (as fast as possible, 20, or 40 minutes). This report describes the synthesis of the 76 PuO 2 specimens. The characterization of these specimens will be described in separate reports.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2025

Autonomous Synthesis of Metastable Materials Using a Modular Mixed-Flow Reactor

Understanding and controlling atomic-level processes at solid-liquid interfaces is key to advancing technologies in energy storage, carbon capture, critical element recovery, and materials synthesis. Many of these processes are dominated by the formation of short-lived intermediate precipitates that determine the final properties of synthesized materials. However, studying these intermediates is challenging due to their sensitivity and the reliance on trial-and-error methods. To address this, we developed an automated variable-volume mixed-flow reactor (MFR) to optimize metastable material synthesis and investigate rapid kinetic processes. This state-of-the-art MFR system, paired with an automated modeling framework, enables efficient synthesis and real-time analysis of transient phases. Benchmarking with advanced capabilities, such as wide-/small-angle X-ray scattering, allows us to resolve fast nucleation and growth dynamics that were previously inaccessible. By combining automation, ML-guided optimization, and tailored kinetic modeling, this approach provides a robust platform for improving material design and achieving precise control over solid-liquid reactions.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Technical and Economic Assessment and Gap Analysis of Advanced Nuclear Reactor Integration with a Reference Methanol Synthesis Plant

Efforts continue to identify the most-economic methods to decarbonize several sectors of the United States (U.S.) economy. Industrial processes such as synfuel synthesis and high value commodity chemicals rely heavily on energy-dense and easily stored and transported fossil fuels, which power and feed their operations. Steam methane reforming (SMR) is a widely used process for producing methanol. In this process, methane (CH 4 ) from natural gas (NG) reacts with steam (H 2 O) over a catalyst at high temperatures (700°1,000°C) to produce syngas, a mixture of hydrogen (H 2 ) and carbon monoxide (CO). The syngas is then converted into methanol (CH 3 OH) through a second catalytic reaction. This method is known for being an efficient and commonly employed pathway for industrial methanol production. The high-temperature heat needed for SMR, which is currently used in the natural-gas-to-methanol process, cannot be supplied by small modular nuclear reactor (SMNR) direct heating; the temperatures required for the SMR process exceed those of the main steam produced by near-market high-temperature gas reactors (HTGRs). For the conventional methanol process, this leaves possible nuclear-integration opportunities that include: (1) blending nuclear hydrogen into the SMR NG fuel, or (2) assessing alternative synthesis routes leveraging nuclear capabilities and steam electrolysis outputs. In the reference methanol plant, SMR provides the methanol-synthesis reactor with H 2 and co. In Case (2), the state-of-the-art reverse water gas shift (RWGS) pathway achieves the same, sourcing carbon from an industrial CO 2 source.

08 - HYDROGEN↗