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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

Advanced Curation of Current and Future Extraterrestrial Samples

Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. Curation includes documentation, preservation, preparation, and distribution of samples. The current collections of extraterrestrial samples include: Lunar rocks / soils collected by the Apollo astronauts Meteorites, including samples of asteroids, the Moon, and Mars "Cosmic dust" (asteroid and comet particles) collected by high-altitude aircraft Solar wind atoms collected by the Genesis spacecraft Comet particles collected by the Stardust spacecraft Interstellar dust collected by the Stardust spacecraft Asteroid particles collected by the Hayabusa spacecraft These samples were formed in environments strikingly different from that on Earth. Terrestrial contamination can destroy much of the scientific significance of many extraterrestrial materials. In order to preserve the research value of these precious samples, contamination must be minimized, understood, and documented. In addition the samples must be preserved - as far as possible - from physical and chemical alteration. In 2011 NASA selected the OSIRIS-REx mission, designed to return samples from the primitive asteroid 1999 RQ36 (Bennu). JAXA will sample C-class asteroid 1999 JU3 with the Hayabusa-2 mission. ESA is considering the near-Earth asteroid sample return mission Marco Polo-R. The Decadal Survey listed the first lander in a Mars sample return campaign as its highest priority flagship-class mission, with sample return from the South Pole-Aitken basin and the surface of a comet among additional top priorities. The latest NASA budget proposal includes a mission to capture a 5-10 m asteroid and return it to the vicinity of the Moon as a target for future sampling. Samples, tools, containers, and contamination witness materials from any of these missions carry unique requirements for acquisition and curation. Some of these requirements represent significant advances over methods currently used. New analytical and screening techniques will increase the value of current sample collections. Improved web-based tools will make information on all samples more accessible to researchers and the public. Advanced curation of current and future extraterrestrial samples includes: Contamination Control - inorganic / organic Temperature of preservation - subfreezing / cryogenic Non-destructive preliminary examination - X-ray tomography / XRF mapping / Raman mapping Microscopic samples - handling / sectioning / transport Special samples - unopened lunar cores Informatics - online catalogs / community-based characterization.

Allen, Carlton C.↗
NASA NTRS2013

Atmospheric Processing Module for Mars Propellant Production

The multi-NASA center Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methane/oxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (~8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO2 is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a HiCO2 recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO2/hr for 14 hr, (3) the testing of the CO2 freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH4/hr and 71.3 g H20/hr along with verification of their purity. The resulting 2.22 kg of CH4/O2 propellant per 14 hr day (including O2 from electrolysis of water recovered from regolith, which also supplies the H2 for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASA's new Mars exploration plans will be discussed.

Muscatello, Anthony↗
NASA NTRS2014

Atmospheric Processing Module for Mars Propellant Production

The multi-NASA center Mars Atmosphere and Regolith COllectorPrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methaneoxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO(sub 2) is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a H(sub 2)CO(sub 2) recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO(sub 2) hr for 14 hr, (3) the testing of the CO(sub 2) freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH(sub 4) hr and 71.3 g H(sub 2)O hr along with verification of their purity. The resulting 2.22 kg of CH(sub 2)O(sub 2) propellant per 14 hr day (including O(sub 2) from electrolysis of water recovered from regolith, which also supplies the H(sub 2) for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASAs new Mars exploration plans will be discussed.

waste treatment↗
NASA NTRS2014

Atmospheric Processing Module for Mars Propellant Production

The multi-NASA center Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methaneoxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (approx. 8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO(sub 2) is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a H(sub 2)CO(sub 2) recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO(sub 2) hr for 14 hr, (3) the testing of the CO(sub 2) freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH(sub 4) hr and 71.3 g H(sub 2)O hr along with verification of their purity. The resulting 2.22 kg of CH(sub 2)O(sub 2) propellant per 14 hr day (including O(sub 2) from electrolysis of water recovered from regolith, which also supplies the H(sub 2) for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASAs new Mars exploration plans will be discussed.

hydrocarbon fuel production↗
NASA NTRS2016

Water Electrolysis for In-Situ Resource Utilization (ISRU)

Sending humans to Mars for any significant amount of time will require capabilities and technologies that enable Earth independence. To move towards this independence, the resources found on Mars must be utilized to produce the items needed to sustain humans away from Earth. To accomplish this task, NASA is studying In Situ Resource Utilization (ISRU) systems and techniques to make use of the atmospheric carbon dioxide and the water found on Mars. Among other things, these substances can be harvested and processed to make oxygen and methane. Oxygen is essential, not only for sustaining the lives of the crew on Mars, but also as the oxidizer for an oxygen-methane propulsion system that could be utilized on a Mars ascent vehicle. Given the presence of water on Mars, the electrolysis of water is a common technique to produce the desired oxygen. Towards this goal, NASA designed and developed a Proton Exchange Membrane (PEM) water electrolysis system, which was originally slated to produce oxygen for propulsion and fuel cell use in the Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project. As part of the Human Exploration Spacecraft Testbed for Integration and Advancement (HESTIA) project, this same electrolysis system, originally targeted at enabling in situ propulsion and power, operated in a life-support scenario. During HESTIA testing at Johnson Space Center, the electrolysis system supplied oxygen to a chamber simulating a habitat housing four crewmembers. Inside the chamber, oxygen was removed from the atmosphere to simulate consumption by the crew, and the electrolysis system's oxygen was added to replenish it. The electrolysis system operated nominally throughout the duration of the HESTIA test campaign, and the oxygen levels in the life support chamber were maintained at the desired levels.

Lee, Kristopher A.↗
NASA NTRS2017

Space Resource Technologies

PowerPoint presentation for the Society of Women Engineers presented by Rachel Cox to give an overview of NASA Swamp Works, the kind of work we do, explain what ISRU (living off the land in space) is about, and highlight several projects. Projects include RASSOR the space mining robot, Resource Prospector, ALTIP, Marco Polo, and regolith construction, including heat shields and 3D printing. Content is similar to what is presented on Swamp Works tours (we get about 2,000 visitors a year) and is high level and conceptual in nature (no engineering specsdimensions.)

Cox, Rachel↗
DOE OSTI2022

Boosting the Activity of Pd Single Atoms by Tuning Their Local Environment on Ceria for Methane Combustion

Abstract Supported Pd single atom catalysts (SACs) have triggered great research interest in methane combustion yet with contradicting views on their activity and stability. Here, we show that the Pd SAs can take different electronic structure and atomic geometry on ceria support, resulting in different catalytic properties. By a simple thermal pretreatment to ceria prior to Pd deposition, a unique anchoring site is created. The Pd SA, taking this site, can be activated to Pd δ + (0< δ <2) that has greatly enhanced activity for methane oxidation: T 50 lowered by up to 130 °C and almost 10 times higher turnover frequency compared to the untreated catalyst. The enhanced activity of Pd δ + site is related to its oxygen‐deficient local structure and elongated interacting distance with ceria, leading to enhanced capability in delivering reactive oxygen species and decomposing reaction intermediates. This work provides insights into designing highly efficient Pd SACs for oxidation reactions.

Yang, Weiwei↗
DOE OSTI2023

Significant Roles of Surface Hydrides in Enhancing the Performance of Cu/BaTiO 2.8 H 0.2 Catalyst for CO 2 Hydrogenation to Methanol

Abstract Tuning the anionic site of catalyst supports can impact reaction pathways by creating active sites on the support or influencing metal‐support interactions when using supported metal nanoparticles. This study focuses on CO 2 hydrogenation over supported Cu nanoparticles, revealing a 3‐fold increase in methanol yield when replacing oxygen anions with hydrides in the perovskite support (Cu/BaTiO 2.8 H 0.2 yields ~146 mg/h/gCu vs. Cu/BaTiO 3 yields ~50 mg/h/gCu). The contrast suggests that significant roles are played by the support hydrides in the reaction. Temperature programmed reaction and isotopic labelling studies indicate that BaTiO 2.8 H 0.2 surface hydride species follow a Mars van Krevelen mechanism in CO 2 hydrogenation, promoting methanol production. High‐pressure steady‐state isotopic transient kinetic analysis (SSITKA) studies suggest that Cu/BaTiO 2.8 H 0.2 possesses both a higher density and more active and selective sites for methanol production compared to Cu/BaTiO 3 . An operando high‐pressure diffuse reflectance infrared spectroscopy (DRIFTS)‐SSITKA study shows that formate species are the major surface intermediates over both catalysts, and the subsequent hydrogenation steps of formate are likely rate‐limiting. However, the catalytic reactivity of Cu/BaTiO 2.8 H 0.2 towards the formate species is much higher than Cu/BaTiO 3 , likely due to the altered electronic structure of interface Cu sites by the hydrides in the support as validated by density functional theory (DFT) calculations.

He, Yang↗
DOE OSTI2022

Boosting the Activity of Pd Single Atoms by Tuning Their Local Environment on Ceria for Methane Combustion

Supported Pd single atom catalysts (SACs) have triggered great research interest in methane combustion yet with contradicting views on their activity and stability. Here, in this paper, we show that the Pd SAs can take different electronic structure and atomic geometry on ceria support, resulting in different catalytic properties. By a simple thermal pretreatment to ceria prior to Pd deposition, a unique anchoring site is created. The Pd SA, taking this site, can be activated to Pd δ+ (0<δ<2) that has greatly enhanced activity for methane oxidation: T 50 lowered by up to 130 °C and almost 10 times higher turnover frequency compared to the untreated catalyst. The enhanced activity of Pd δ+ site is related to its oxygen-deficient local structure and elongated interacting distance with ceria, leading to enhanced capability in delivering reactive oxygen species and decomposing reaction intermediates. This work provides insights into designing highly efficient Pd SACs for oxidation reactions.

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

Significant Roles of Surface Hydrides in Enhancing the Performance of Cu/BaTiO 2.8 H 0.2 Catalyst for CO 2 Hydrogenation to Methanol

A BaTiO 3 lattice is shown in the background of the cover picture, with the stack of orange balls symbolizing Cu nanoparticles. Pipes delivering the reactants and products have the shapes of H — and e — indicating they are involved in the catalytic hydrogenation of CO 2 . Lattice O is replaced with hydrides for the enhanced performance in CO 2 hydrogenation to methanol, as demonstrated by Zili Wu et al. in their Research Article (e202313389).

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

On‐Surface Synthesis and Determination of the Open‐Shell Singlet Ground State of Tridecacene**

Abstract The character of the electronic structure of acenes has been the subject of longstanding discussion. However, convincing experimental evidence of their open‐shell character has so far been missing. Here, we present the on‐surface synthesis of tridecacene molecules by thermal annealing of octahydrotridecacene on a Au(111) surface. We characterized the electronic structure of the tridecacene by scanning probe microscopy, which reveals the presence of an inelastic signal at 126 meV. We attribute the inelastic signal to spin excitation from the singlet diradical ground state to the triplet excited state. To rationalize the experimental findings, we carried out many‐body ab initio calculations as well as model Hamiltonians to take into account the effect of the metallic substrate. Moreover, we provide a detailed analysis of how the dynamic electron correlation and virtual charge fluctuation between the molecule and metallic surface reduces the singlet‐triplet band gap. Thus, this work provides the first experimental confirmation of the magnetic character of tridecacene.

Chemistry↗
DOE OSTI2025

Cu Evolution over Bimetallic Cu‐Y/Beta Zeolite Under H 2 and Ethanol Atmospheres: Unveiling the Role of Diatomic Metal–Metal Interactions

Understanding the dynamic evolution of Cu species under varying environmental conditions is critical for addressing challenges related to the activity and the stability of copper‐based catalysts in thermo‐, photo‐, and electrocatalysis. However, metal–metal interactions between dual single atoms and their effects on Cu evolution after exposure to different environmental molecules remain underexplored. Herein, we synthesized bimetallic Cu‐Y/Beta catalysts with dual single‐atom Cu and Y sites and monometallic Cu‐Beta catalysts with isolated Cu sites in dealuminated Beta zeolites. By varying Cu and Y compositions, diatomic interactions were studied under H 2 and ethanol atmospheres. With 6 wt% Y loading, approximately 0.4 wt% of Cu species in Cu‐Y/Beta remained partially oxidized as Cu(I) after reduction in pure H 2 at 350 °C, in contrast to the full transition to metallic Cu observed in Cu‐Beta. Combining X‐ray absorption spectroscopy with kinetic studies revealed that metallic Cu became the predominant species after reduction with H 2 as Cu loading increased from 0.4 to 1.7 wt%, quadrupling the initial ethanol dehydrogenation rate and demonstrating the dominant role of Cu(0) sites. In conclusion, scanning transmission electron microscopy and density functional theory simulations indicated spatial proximity between dual single‐atom Cu and Y sites and elucidated Cu speciation controlled by diatomic interactions.

Copper↗
DOE OSTI2026

pH‐Mediated Strong Metal‐Support Interaction Construction Through Dynamic Fermi Level Tuning

The metal–support interface is central to governing catalytic transformations. While strong metal–support interaction (SMSI) is an established strategy to tailor the morphology and electronic properties of supported metal catalysts, the role of interfacial charge redistribution in SMSI formation remains poorly understood and rarely leveraged. Here, in this study, we report a dual-stimuli approach that combines pH modulation with ultrasonication to mediate SMSI construction in aqueous solution through dynamic Fermi level tuning. By leveraging in situ pH-driven charge redistribution at the metal–support interface, we achieve controllable SMSI encapsulation of metal nanoparticles, as verified by electrochemical analysis, work function measurements, and x-ray-based techniques. The resulting catalysts exhibit tunable SMSI features and deliver enhanced activity and selectivity in hydrogenation reactions. This work establishes a facile strategy to modulate catalyst structure and electronic properties by exploiting Fermi level variation as a driving force, thereby advancing rational SMSI design and catalytic performance across diverse environments.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2021

Morphology, microstructure, and doping behaviour: A comparison between different deposition methods for poly-Si/SiO x passivating contacts

In this work, we study how crystallographic structures, optoelectronic properties, and nanoscale surface morphologies of ex situ phosphorus-doped polycrystalline silicon (poly-Si)/SiO x passivating contacts, formed by different deposition methods (sputtering, plasma-enhanced chemical vapour deposition [PECVD], and low-pressure chemical vapour deposition [LPCVD]), are investigated and compared. Across all these deposition technologies, we noted the same trend: higher diffusion temperatures yield films that are more crystalline but that have rougher surface morphologies due to bigger surface crystal grains. Also, the recrystallization process of the as-deposited Si films starts from the SiO x interface, rather than from the film surface and bulk. However, there are some distinct differences among these technologies. First, the LPCVD method yields the lowest deposition rate, roughest surfaces, and smallest degree of crystallinity on finished poly-Si films. In contrast, the PECVD method has the highest deposition rate and smoothest surfaces for both as-deposited Si and annealed poly-Si films. Second, as-deposited sputtered and PECVD Si films contain only an amorphous phase, whereas as-deposited LPCVD films already has some crystalline phase. Third, the LPCVD phosphorus in-diffusion into the substrate depends strongly on the initial film thickness, whereas for the other two methods, it is weakly dependent on thickness. Finally, the passivation quality of every poly-Si film type has different responses to the film thickness and diffusion temperature, suggesting that the ex situ doping optimization should be performed independently.

14 SOLAR ENERGY↗
DOE OSTI2023

Blind photovoltaic modeling intercomparison: A multidimensional data analysis and lessons learned

The Photovoltaic (PV) Performance Modeling Collaborative (PVPMC) organized a blind PV performance modeling intercomparison to allow PV modelers to blindly test their models and modeling ability against real system data. Measured weather and irradiance data were provided along with detailed descriptions of PV systems from two locations (Albuquerque, New Mexico, USA, and Roskilde, Denmark). Participants were asked to simulate the plane-of-array irradiance, module temperature, and DC power output from six systems and submit their results to Sandia for processing. The results showed overall median mean bias (i.e., the average error per participant) of 0.6% in annual irradiation and –3.3% in annual energy yield. While most PV performance modeling results seem to exhibit higher precision and accuracy as compared to an earlier blind PV modeling study in 2010, human errors, modeling skills, and derates were found to still cause significant errors in the estimates.

14 SOLAR ENERGY↗
DOE OSTI2021

Investigation of Gallium–Boron Spin-On Codoping for poly-Si/SiO x Passivating Contacts

A doping technique for p-type poly-Si/SiOx passivating contacts using a spin-on method for different mixtures of Ga and B glass solutions is presented. Effects of solution mixing ratios on the contact performance (implied open circuit voltage iV oc , contact resistivity ..rho..c) are investigated. For all as-annealed samples at different drive-in temperatures, increasing the percentage of Ga in the solution shows a decrement in iV oc (from ~680 to ~610 mV) and increment in ..rho..c (from ~3 to ~800 mO cm 2 ). After a hydrogenation treatment by depositing a SiN x /AlO x stack followed by forming gas annealing, all samples show improved iVoc (~700 mV with Ga-B co-doped, and ~720 mV with all Ga). Interestingly, when co-doping Ga with B, even a small amount of B in the mixing solution shows negative effects on the surface passivation. Active and total dopant profiles obtained by electrical capacitance voltage and secondary-ion mass spectrometry measurements, respectively, reveal a relatively low percentage of electrically-active Ga and B in the poly-Si and Si layers. Overall, these results help understand the different features of the two dopants: a low ρ c with B, a good passivation with Ga, their degree of activation inside the poly-Si and Si layers, and the annealing effects.

14 SOLAR ENERGY↗