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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 1,027 records · Page 57
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

An Open-Source Decarbonization Analytics Framework: Designing for Low-Carbon Emission Districts and Communities: Preprint

This paper introduces an open-source analytics framework designed to assist in creating low or net-zero carbon buildings and urban districts. Integrated within URBANopt, an open-source platform for energy analysis in districts and communities, this framework equips researchers, architects, engineers, and other stakeholders with tools to evaluate the carbon footprint implications of their design choices. The framework enables the analysis of various scenarios, incorporating both historical and future emission factors, and can span across different climate zones, each with distinct grid and emissions characteristics. The results showcase the framework's capability to evaluate the impact of design upgrades and control strategies on carbon emissions in districts and communities. An illustrative analysis using a hypothetical district in Denver, Colorado, shows reduced emissions from energy efficiency upgrades and control strategies, highlighting the sensitivity in their effects on emissions and energy use.

buildings energy efficiency↗
DOE OSTI2024

A Scalable Real-Time Data Assimilation Framework for Predicting Turbulent Atmosphere Dynamics

AI-based foundation models like FourCastNet, GraphCast are revolutionizing weather and climate predictions but are not yet ready for operational use. Their limitation lies in the absence of a data assimilation system to incorporate real-time Earth system observations, crucial for accurately forecasting events like tropical cyclones. To overcome these obstacles, we introduce a generic real-time data assimilation framework and demonstrate its end-to-end performance on the Frontier supercomputer. This framework comprises two primary modules: an ensemble score filter (EnSF), which significantly outperforms the state-of-the-art data assimilation method, and a vision transformer-based surrogate capable of real-time adaptation through the integration of observational data. We demonstrate both the strong and weak scaling of our framework up to 1024 GPUs on the Exascale supercomputer, Frontier. Our results not only illustrate the framework's exceptional scalability on high-performance computing systems, but also demonstrate the importance of supercomputers in real-time data assimilation for weather and climate predictions.

Lu, Dan↗
DOE OSTI2017

Sn Nanoparticles Encapsulated in 3D Nanoporous Carbon Derived from a Metal–Organic Framework for Anode Material in Lithium-Ion Batteries

Three-dimensional nanoporous carbon frameworks encapsulated Sn nanoparticles (Sn@3D-NPC) are developed by a facile method as an improved lithium ion battery anode. The Sn@3D-NPC delivers a reversible capacity of 740 mAh g –1 after 200 cycles at a current density of 200 mA g –1 , corresponding to a capacity retention of 85% (against the second capacity) and high rate capability (300 mAh g –1 at 5 A g –1 ). Compared to the Sn nanoparticles (SnNPs), such improvements are attributed to the 3D porous and conductive framework. The whole structure can provide not only the high electrical conductivity that facilities the electron transfer but also the elasticity that will suppress the volume expansion and aggregation of SnNPs during the charge and discharge process. Lastly, this work opens a new application of metal–organic frameworks in energy storage.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Unusual Metal–Organic Framework Topology and Radiation Resistance through Neptunyl Coordination Chemistry

A Np(V) neptunyl metal–organic framework (MOF) with rod-shaped secondary building units was synthesized, characterized, and irradiated with γ rays. Furthermore, single-crystal X-ray diffraction data revealed an anionic framework containing infinite helical chains of actinyl–actinyl interaction (AAI)-connected neptunyl ions linked together through tetratopic tetrahedral organic ligands (NSM). NSM exhibits an unprecedented net, demonstrating that AAIs may be exploited to give new MOFs and new topologies. To probe its radiation stability, we undertook the first irradiation study of a transuranic MOF and its organic linker building block using high doses of γ rays. Diffraction and spectroscopic data demonstrated that the radiation resistance of NSM is greater than that of its linker building block alone. Approximately 6 MGy of irradiation begins to induce notable changes in the long- and short-range order of the framework, whereas 3 MGy of irradiation induces total X-ray amorphization and changes in the local vibrational bands of the linker building block.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Distributed Energy Resources Cybersecurity Framework: Applying the NIST Risk Management Process

In an effort to strengthen the cybersecurity posture for federal agencies and reduce the time and complexities of following the Risk Management Framework (RMF) six-step process, the National Renewable Energy Laboratory has dedicated research into expanding the existing Distributed Energy Resources Cybersecurity Framework to provide functionality that aids in the RMF steps. Users will have the opportunity to learn, document, and review the framework, saving time and resources. Existing functionality within the web application will continue to be available with added features for usability.

14 SOLAR ENERGY↗
DOE OSTI2017

“Wiring” Fe-N x -Embedded Porous Carbon Framework onto 1D Nanotubes for Efficient Oxygen Reduction Reaction in Alkaline and Acidic Media

This study presents a novel metal-organic-framework-engaged synthesis route based on porous tellurium nanotubes as a sacrificial template for hierarchically porous 1D carbon nanotubes. Furthermore, an ultrathin Fe-ion-containing polydopamine layer has been introduced to generate highly effective FeN x C active sites into the carbon framework and to induce a high degree of graphitization. The synergistic effects between the hierarchically porous 1D carbon structure and the embedded FeN x C active sites in the carbon framework manifest in superior catalytic activity toward oxygen reduction reaction (ORR) compared to Pt/C catalyst in both alkaline and acidic media. A rechargeable zinc-air battery assembled in a decoupled configuration with the nonprecious pCNT@Fe@GL/CNF ORR electrode and Ni-Fe LDH/NiF oxygen evolution reaction (OER) electrode exhibits charge–discharge overpotentials similar to the counterparts of Pt/C ORR electrode and IrO 2 OER electrode.

1D nanotubes↗
DOE OSTI2022

Crystal Prediction and Design of Tunable Light Emission in BTB–Based Metal–Organic Frameworks

Metal-organic frameworks (MOFs) have recently been shown to exhibit unique mechanisms of luminescence based on charge transfer between structural units in the framework. These MOFs have the potential to be structural tuned for targeted emission with little or no metal participation. Here a computationally led, material design and synthesis methodology is presented that elucidates the mechanisms of light emission in interpenetrated structures comprised of metal centers (M = In, Ga, InGa, InEu) and BTB (1,3,5-Tris(4-carboxyphenyl)benzene) linkers, forming unique luminescent M-BTB MOF frameworks. Gas phase and periodic electronic structure calculations indicate that the intensity of the emission and the wavelength are overwhelmingly controlled by a combination of the number of interacting stacked linkers and their interatomic spacings, respectively. In the MOF, the ionic radii of the metal centers primarily control the expansion or shrinkage of the linker stacking distances. Experimentally, multiple M-BTB-based MOFs are synthesized and their photoluminescence was tested. Experiments validated the modeling by confirming that shifts in the crystal structure result in variations in light emission. Through this material design method, the mechanisms of tuning luminescence properties in interpenetrated M-BTB MOFs have been identified and applied to the design of MOFs with specific wavelength emission based on their structure.

36 MATERIALS SCIENCE↗
DOE OSTI2020

High-Pressure Synthesis of Metal–Inorganic Frameworks Hf 4 N 20 •N 2 , WN 8 •N 2 , and Os 5 N 28 •3N 2 with Polymeric Nitrogen Linkers

Polynitrides are intrinsically thermodynamically unstable at ambient conditions and require peculiar synthetic approaches. Now, a one-step synthesis of metal–inorganic frameworks Hf 4 N 20 •N 2 , WN 8 •N 2 , and Os 5 N 28 •3N 2 via direct reactions between elements in a diamond anvil cell at pressures exceeding 100 GPa is reported. The porous frameworks (Hf 4 N 20 , WN 8 , and Os 5 N 28 ) are built from transition-metal atoms linked either by polymeric polydiazenediyl (polyacetylene-like) nitrogen chains or through dinitrogen units. Triply bound dinitrogen molecules occupy channels of these frameworks. Owing to conjugated polydiazenediyl chains, these compounds exhibit metallic properties. The high-pressure reaction between Hf and N 2 also leads to a non-centrosymmetric polynitride Hf 2 N 11 that features double-helix catena-poly[tetraz-1-ene-1,4-diyl] nitrogen chains [–N–N–N=N–] ∞ .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Hypercrosslinked phenolic polymers with well developed mesoporous frameworks

A soft chemistry synthetic strategy based on a Friedel Crafts alkylation reaction is developed for the textural engineering of phenolic resin (PR) with a robust mesoporous framework to avoid serious framework shrinkage and maximize retention of organic functional moieties. By taking advantage of the structural benefits of molecular bridges, the resultant sample maintains a bimodal micro-mesoporous architecture with well-preserved organic functional groups, which is effective for carbon capture. Furthermore, this soft chemistry synthetic protocol can be further extended to nanotexture other aromatic-based polymers with robust frameworks.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

“Interpenetration Isomerism” of Triptycene-Based Hydrogen-Bonded Organic Frameworks

In this work, we describe an example of “interpenetration isomerism” in three-dimensional (3D) hydrogen-bonded organic frameworks (HOFs). By exploiting the crystallization conditions for a peripherally extended triptycene H6PET, we can modulate the interpenetration of the assembled frameworks, yielding a two-fold interpenetrated structure PETHOF-1 (acs-2c topology) and a five-fold interpenetrated structure PETHOF-2 (acs-5c topology) as “interpenetration isomers”. In PETHOF-1, two individual nets are related by inversion symmetry and form an interwoven topology with a strikingly large guest-accessible volume of about 80%. In PETHOF-2, five individual nets are related by translational symmetry and are stacked in an alternating fashion. Additionally, the activated materials show permanent porosity with high Brunauer–Emmett–Teller (BET) areas exceeding 1100 m2•g-1. Finally, we believe that synthetic control over the framework interpenetration can serve as a new design strategy to construct diverse and complex supramolecular architectures from simple organic building blocks.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Isoreticular Linker Substitution in Conductive Metal–Organic Frameworks with Through–Space Transport Pathways

The extension of reticular chemistry concepts to electrically conductive three-dimensional metal–organic frameworks (MOFs) has been challenging, particularly for cases in which strong interactions between electroactive linkers create the charge transport pathways. Here, we report the successful replacement of tetrathiafulvalene (TTF) with a nickel glyoximate core in a family of isostructural conductive MOFs with Mn 2+ , Zn 2+ , and Cd 2+ . Different coordination environments of the framework metals lead to variations in the linker stacking geometries and optical properties. Single-crystal conductivity data are consistent with charge transport along the linker stacking direction, with conductivity values only slightly lower than those reported for the analogous TTF materials. Lastly, these results serve as a case study demonstrating how reticular chemistry design principles can be extended to conductive frameworks with significant intermolecular contacts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

A modified eco-efficiency framework and methodology for advancing the state of practice of sustainability analysis as applied to green infrastructure: Sustainability Analysis of Rainwater Harvesting

We propose a modified eco-efficiency (EE) framework and novel sustainability analysis methodology for green infrastructure (GI) practices used in water resource management. Green infrastructure practices such as rainwater harvesting (RWH), rain gardens, porous pavements, and green roofs are emerging as viable strategies for climate change adaptation. The modified framework includes 4 economic, 11 environmental, and 3 social indicators. Using 6 indicators from the framework, at least 1 from each dimension of sustainability, we demonstrate the methodology to analyze RWH designs. We use life cycle assessment and life cycle cost assessment to calculate the sustainability indicators of 20 design configurations as Decision Management Objectives (DMOs). Five DMOs emerged as relatively more sustainable along the EE analysis Tradeoff Line, and we used Data Envelopment Analysis (DEA), a widely applied statistical approach, to quantify the modified EE measures as DMO sustainability scores. We also addressed the subjectivity and sensitivity analysis requirements of sustainability analysis, and we evaluated the performance of 10 weighting schemes that included classical DEA, equal weights, National Institute of Standards and Technology’s stakeholder panel, Eco-Indicator 99, Sustainable Society Foundation’s Sustainable Society Index, and 5 derived schemes. We improved upon classical DEA by applying the weighting schemes to identify sustainability scores that ranged from 0.18 to 1.0, avoiding the nonuniqueness problem and revealing the least to most sustainable DMOs. Our methodology provides a more comprehensive view of water resource management and is generally applicable to GI and industrial, environmental, and engineered systems to explore the sustainability space of alternative design configurations.

Sustainability Rainwater harvesting↗
DOE OSTI2020

Nanosized Zirconium Porphyrinic Metal–Organic Frameworks that Catalyze the Oxygen Reduction Reaction in Acid

Porphyrinic metal–organic frameworks (PMOFs) are very appealing electrocatalytic materials, in part, due to their highly porous backbone, well-defined and dispersed metal active sites, and their long-range order. Herein a series of (Co)PCN222 (PCN: porous coordination network) (nano)particles with different sizes are successfully prepared by coordination modulation synthesis. These particles exhibit stability in 0.1 M HClO 4 electrolyte with no obvious particle size or compositional changes observed after being soaked for 3 days in the electrolyte or during electrocatalysis. This long-term stability enables the in-depth investigation into the electrocatalytic oxygen reduction, and it is further demonstrated that the (Co)PCN222 particle size correlates with its catalytic activity. Of the three particle sizes evaluated (characteristic length scales of 200, 500, and 1000 nm), the smallest size demonstrates the highest mass activity while the largest size has the highest surface area normalized activity. Together these results highlight the importance of determining the structural stability of framework catalysts and provide insights into the important roles of particle size, opening new avenues to investigate and improve the electrocatalytic performance of this class of framework material.

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

ADC evaluation boards design and test framework for LCLS-II precision receiver

In the low-level RF control field, ADC acquisition accuracy and noise set the boundary of our control ability, making it important to develop low-noise acquisition systems. From the design to test stage, all the noise terms should be understood and characterized. The specific need addressed here is the precision acquisition system for the second Linac Coherent Light Source (LCLS-II), led by SLAC National Accelerator Laboratory. Test circuit boards for the LTC2174 and AD9268 ADCs are designed and fabricated by LBNL. An ADC test framework based on FPGA evaluation board to assess performance has been developed. The ADC test framework includes both DSP (Digital Signal Processing) firmware and processing software. It is useful for low-level RF control and other synchronization projects. Investigating the clock jitter between two channels give us an understanding of that noise source. Working with the test framework, the raw ADC data are transferred to a computer through a Gigabit Ethernet interface. Then short-term error signal can be calculated based on a sine wave fit. By changing low-pass filter bandwidth, relative long-term performance can also be obtained. Amplitude jitter and differential phase jitter are the key issues for ADCs. This paper will report the test results for LTC2174 and AD9268 chips. The integral amplitude jitter is smaller than 0.003 %, and the integral phase noise is smaller than 0.0015° (measured at 47 MHz RF, 100 MHz clock, bandwidth 1 Hz to 100 kHz) for both ADC chips.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Lithiophilic V 2 O 5 nanobelt arrays decorated 3D framework hosts for highly stable composite lithium metal anodes

The lithium metal anode has been considered to be an optimal anode material for high-energy-density battery system due to its ultrahigh specific capacity. However, the sharp dendrite growth and infinite volume expansion have significantly impeded its commercial application. In this paper, we propose that V 2 O 5 as the lithiophilic substance can be decorated onto 3D stable frameworks to fabricate dendrite-suppressed composite Li metal anodes via a molten Li infusion method. It is demonstrated that the energetic chemical reaction between V 2 O 5 and molten Li together with the capillary effect based on the nanostructure of interconnected V 2 O 5 nanobelt arrays contributes synergistically to the great Li affinity of the V 2 O 5 -Ni foam (V 2 O 5 -NF) host and facilitate the efficient and uniform intake of molten Li into the 3D framework. Benefitting from the homogeneous Li distribution in the framework, the decreased local current density of the electrode and the stable property of the host, dendrite-free Li stripping/plating behavior and alleviated volume fluctuation have been achieved for the Li-V 2 O 5 -NF composite anode. Compared with the bare Li anode, the as-obtained Li-V 2 O 5 -NF composite anode exhibits much stable stripping/plating profiles with low overpotential (~18 mV) for ultralong lifespan (1600 h) at a current density of 1 mA cm -2 in symmetric Li/Li cell. Furthermore, outstanding rate capability and long-term cycling performance (78.8% capacity retention after 500 cycles under 2 C) are obtained in full cells when coupled with Li 4 Ti 5 O 12 (LTO) cathodes, indicating a promising potential for practical application. Moreover, this work demonstrates that using a new lithiophilic material, V 2 O 5 , should be an effective method to construct high stable 3D Li metal anode for Li metal battery.

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

A fast computational framework for the design of solvent-based plastic recycling processes

Multicomponent plastics cannot be processed using mechanical recycling technologies, hindering efforts to deal with plastic waste. Multicomponent plastics include multilayer plastic films, which are widely used for food and healthcare packaging. Multilayer films combine several layers (potentially dozens) of different polymers to protect products from external factors (e.g., oxygen, water, temperature, shock, and light). Solvent-based separation processes have emerged as a promising alternative to recycle these complex materials. For instance, the Solvent-Targeted Recovery and Precipitation (STRAP TM ) process uses sequential solvent washes to selectively dissolve and separate constituent polymers from multicomponent plastic waste, including films. STRAP TM process design (separation sequence, type of solvents, and operating conditions) changes significantly depending on the design of the multilayer plastic film (e.g., number, types, and proportions of polymers). The ability to quickly quantify the economic and environmental benefits of diverse STRAP TM process designs is essential to accelerate the development of sustainable recycling processes and more recyclable multilayer film products. In this work, we present a fast computational framework that integrates molecular-scale models, process modeling, and techno-economic and life cycle analysis to quickly evaluate STRAP TM designs. The computational framework is general and can be used to study the processing of complex multilayer plastic waste streams that contain many layers. Furthermore, we highlight the different uses of the framework via targeted case studies.

Computational framework↗
DOE OSTI2018

A framework for monitoring-based commissioning: Identifying variables that act as barriers and enablers to the process

The practice of monitoring-based commissioning (MBCx) using energy management and information systems (EMIS) has been shown to enable and help sustain up to 20% energy savings in buildings. Despite research that has quantified the costs, benefits, and energy savings of MBCx, the process remains under-utilized. To understand why MBCx is not more frequently adopted and how to encourage its use, this research synthesizes qualitative data from over 40 organizations, currently engaging in MBCx. The outcome of this research is a framework containing variables that emerged from the qualitative data, marked as barriers or enablers, organized by phases of the MBCx process. The framework is comprised of 51 emergent variables that fall within 13 different categories. The variables that most frequently act as barriers are data configuration, measurement & verification (M&V), developing specifications for EMIS, and data architecture. Although some variables that act as barriers for one organization were identified as enablers for another. For example, payback/ROI was considered a barrier 7 times and an enabler 3 times. One organization had difficulty making the business case for the initial investment for MBCx due to lack of cost information, while another was able to justify large investments with documented savings of previously implemented measures identified through MBCx. The framework formally validates barriers found in previous research, and can be used by practitioners to better understand common experiences with MBCx. This research also highlights the need for a similar collective data set to validate common enablers to MBCx and also the need for empirical research to determine relationships between variables.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

Universal molecular-confined synthesis of interconnected porous metal oxides-N-C frameworks for electrocatalytic water splitting

The rational synthesis of high performance electrocatalysts at low cost for water splitting (hydrogen and oxygen evolution reaction, HER and OER) is highly desirable but remains a key challenge. Herein, we report a versatile molecular-confining route to construct strongly coupled metal oxides-N-C frameworks with interconnected configuration. By simply chelating various transition metal ions with ethylenediaminetetraacetic acid disodium salt (EDTA) in agarose hydrogel and subsequent carbonization, the high specific surface area porous N-C frameworks with strongly coupled metal oxides (e.g., manganese, iron, cobalt, nickel and their mixed oxides) can be prepared as advanced nonprecious water splitting electrocatalysts. For instance, the resulting Co 3 O 4 -N-C frameworks with the high surface area of 153 m 2 g -1 , and the moderate nitrogen content of 1.23%, require an overpotential of 324 mV to afford a current density of 10 mA cm -2 in 0.1 M KOH for OER, superior to commercial RuO 2 catalysts. Density functional theory (DFT) calculations reveal that the strong coupling between N-C and Co 3 O 4 tunes the local electronic structure of Co for high-valence active sites and assures optimal adsorption energies of OER intermediates. Moreover, Co 2 P-N-C electrocatalysts derived from Co 3 O 4 -N-C also exhibit excellent HER performance under 1.0 M KOH with a low overpotential of 139 mV to reach 10 mA cm -2 , a small Tafel slope of 45 mV dec -1 and impressive stability, underscoring the versatility of our synthetic strategy.

36 MATERIALS SCIENCE↗