SEARCH · Engineering Papers

Results for “ILs”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,297 records · Page 72

All sources NASA NTRS DOE OSTI

DOE OSTI2025

Strong NIR II Chiroptical Response and Magnetic Anisotropy via Modular Installation of Chiral Capping Ligands on a Light-Emitting Diradicaloid Scaffold

Low-energy molecular lumiphores have seen increased interest due to potential imaging and communications applications. Specifically, molecules that emit in the near-infrared (NIR, 700–1700 nm) or telecom (∼1260–1625 nm) regions, where attenuation is minimized in biological tissue and optical fibers, respectively, can drastically improve image resolution and depth penetration; however, bright low-energy emission is rare due to exponentially decreasing quantum yields in this region. Chiral molecules exhibiting strong NIR or telecom absorption/emission would be of particular interest due to advanced security and spintronics applications, but these compounds remain scarce and are currently restricted to lanthanide or nanoparticle-based systems. Here, we report the synthesis of a chiral organic-based NIR emitter, enabled by simple peripheral installation of chiral capping ligands. These ligands twist the achiral NIR-emissive core, breaking inversion symmetry. Furthermore, this twisting enables strong chiroptical responses observed via static and transient circular dichroism and increased magnetic anisotropy through electron paramagnetic resonance (EPR) measurements, establishing this strategy as a promising method for the development of new chiral emitters and sensors.

Electron paramagnetic resonance spectroscopy↗

DOE OSTI2026

Integrative Additive Design for Robust SEI Formation in NMC811||Silicon Batteries

Silicon (Si) is considered a promising replacement for graphite anodes in lithium-ion batteries (LIBs) due to its high abundance and exceptional specific capacity, but its widespread commercialization has been hindered by poor electrochemical performance. Among various strategies, the use of functional additives has emerged as one of the most effective and cost-efficient methods to enhance the electrochemical properties of LIBs. In this study, several additives—vinylene carbonate (VC), vinyl ethylene carbonate (VEC), lithium difluorophosphate (LiDFP), lithium difluoro(oxalato)borate (LiDFOB), lithium tetrafluorooxalatophosphate (LiTFOP), and lithium difluorobis(oxalato)phosphate (LiDFBOP)—were systematically investigated in LiNi₀.₈Mn₀.₁Co₀.₁O₂ (NMC811)||Si full cells. Notably, LiDFBOP, a lithium salt containing two oxalate groups, outperformed all other additives, delivering the best capacity retention after 300 cycles. Comprehensive characterizations, including FTIR, SEM, and XPS, revealed that LiDFBOP's superior performance stems from its ability to form a more stable solid electrolyte interphase (SEI) on the Si anode, owing to its favorable molecular structure that integrates the beneficial features of the other additives.

25 ENERGY STORAGE↗

DOE OSTI2025

Data-Driven Discovery of Bimetallic Nanoparticles Catalysts for the Hydrogenolysis of Polyethylene

Supported platinum nanoparticles are known to convert polyolefins to high-quality liquid hydrocarbons with hydrogen under relatively mild conditions. However, no systematic study has been undertaken using bimetallic catalysts for polyethylene upcycling. Specifically, a total of 98 monometallic and bimetallic combinations (Ag, Cr, Co, Cu, Fe, Ga, In, Mn, Ni, Pd, Pt, Rh, Ru, Zr) on alumina were synthesized utilizing surface organometallic chemistry (SOMC) technique via robotic platform. These were investigated at a small scale (10 mg of catalyst and 50 mg of polyethylene) for their activity for the hydrogenolysis of polyethylene in a high-throughput batch reactor. Combinations of Ni and Co were selected as candidates with high activity toward conversion into paraffin oils. Reaction conditions were optimized with Ni/Co/Al 2 O 3 catalyst at a larger scale (300 mg catalyst and 3 g polyethylene) to obtain a high yield (93.1%) of paraffin wax with desired properties (M n = 380 Da) and low polydispersity (Đ = 1.2). Ni/Co/Al 2 O 3 was compared against Co/Ni/Al 2 O 3 to understand the role of the deposition sequence. When Co is deposited before Ni, a layer of cobalt aluminate is formed upon reduction, stabilizing the deposition of 5 nm metallic Ni particles. When nickel is deposited before Co, particles are larger (average >20 nm) and more oxidized (Ni δ+ in NiAl 2 O 4 ), decreasing the availability of the catalytically active metallic Ni. In conclusion, the difference in electronic environments was also described by DFT calculations, which revealed that smaller 3D clusters of Ni are preferred on CoAl2O4 over the 3D clusters on NiAl 2 O 4 and that these smaller clusters are more reducible, as confirmed experimentally.

Polymer↗

DOE OSTI2025

Above the Energy Gap Law: Heavy Chalcogenide Substitution in NIR II-Emissive Diradicaloid Qubits

Near-infrared (NIR, 700–1700 nm)- and telecom (∼1260–1625 nm)-emissive molecules are good candidates for biological imaging and quantum sensing applications, respectively; however, bright low energy emission is rare due to exponentially increasing nonradiative decay rates in these regions, a phenomenon known as the energy gap law. Recent literature has emphasized the importance of minimizing skeletal modes to prevent increased nonradiative decay rates, but most organic lumiphores in these regions utilize large, conjugated scaffolds containing many C═C modes. Here we report a compact, telecom-emissive scaffold, tetrathiafulvalene-2,3,6,7-tetraselenate, or TTFts, that displays remarkable air, water, and acid stability, exhibits record quantum yields and brightness values, and retains quantum coherence under ambient conditions. These properties are enabled through methodical selenium substitution, which bathochromically shifts emission while shifting skeletal vibrations to lower energies. This new scaffold validates heavy heteroatom substitution strategies and establishes a new class of bright telecom emitters and robust qubits.

biological imaging↗

DOE OSTI2026

Molecular Diradical Spin Qubits in a Crystalline Host as a Platform for Quantum Sensing

Doping a luminescent tris(2,4,6-trichlorophenyl)methyl diradical m (TTM) 2 into a host crystal of its diamagnetic precursor m (HTTM) 2 creates a molecular color center with enhanced optical-spin interface properties important for quantum sensing. Optical polarization of the |T 0 ⟩ sublevel of the diradical triplet ground state is achieved by spin-selective intersystem crossing from the |T + ⟩ and |T – ⟩ sublevels of the triplet excited state at ambient and cryogenic temperatures. Coherent spin control of m (TTM) 2 doped into m (HTTM) 2 using pulsed optically detected magnetic resonance (ODMR) spectroscopy results in a 10-fold improvement in ODMR contrast over that observed for randomly oriented m (TTM)2 using continuous-wave ODMR. The diradical doped crystal powders achieve spin coherence times of 2.8, 3.4, and 7.4 μs at 294, 85, and 5 K, respectively. The diradical photoluminescence is sensitive to weak applied magnetic fields independent of temperature, excitation wavelength, and dopant concentration, providing a promising pathway toward robust quantum sensing of anisotropic magnetic fields under ambient conditions.

crystal structure↗

DOE OSTI2025

Direct Electrochemical Reduction of CO 2 to C 2+ Chemicals: Catalysts, Microenvironments, and Mechanistic Understanding

The electrochemical reduction reaction of CO 2 (eCO 2 RR) to chemicals presents a viable solution for addressing climate change and sustainable manufacturing. In this Review, we describe the recent advancements in eCO 2 RR for multicarbon (C 2+ ) chemicals production from the aspects of catalyst structure, reaction microenvironments, and mechanistic understanding. Here, we draw experimental and theoretical comparisons between the catalyst systems containing bulk and highly dispersed metals, alloys, and metal compounds and recount new results of microenvironmental impacts as well as the catalytic mechanism. From our own recent studies, we offer some viewpoints on the electrocatalytic mechanism during complex multistep proton-coupled electron transfers and propose several research directions in unlocking the full potential of eCO 2 RR as a scalable industrial solution for CO 2 -to-C 2+ conversion.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2026

Oxidation, Oligomerization, Isomerization of Hydrocarbons Using Metal–Organic Frameworks

The selective conversion of hydrocarbons into higher-value fuels and feedstocks is essential to the global energy and chemistry landscape. While porous inorganic materials have enabled significant progress in these transformations, achieving high activity, selectivity, and stability under industrially relevant conditions remains challenging. Metal–organic frameworks (MOFs) are a promising platform to precisely control active-site environments and interrogate structure–function relationships due to their crystallinity, tunability, and porosity. This review highlights relevant hydrocarbon transformations and outlines the general mechanisms for oxidation, oligomerization, and isomerization. Metal node acidity, confinement effects, and active site dispersion are analyzed for their impact on reactivity and selectivity across the three reactions. Lastly, we discuss current limitations in catalyst stability and offer a perspective on integrating reticular chemistry with high-throughput experimentation and machine learning to accelerate the discovery and design of robust, next-generation MOF catalysts.

Catalysts↗

DOE OSTI2025

Structural Characterization of the Platinum Nanoparticle Hydrogen-Evolving Catalyst Assembled on Photosystem I by Light-Driven Chemistry

Directed assembly of abiotic catalysts onto biological redox protein frameworks is of interest as an approach for the synthesis of biohybrid catalysts that combine features of both synthetic and biological materials. In this report, we provide a multiscale characterization of the platinum nanoparticle (NP) hydrogen-evolving catalysts that are assembled by light-driven reductive precipitation of platinum from an aqueous salt solution onto the photosystem I protein (PSI), isolated from cyanobacteria as trimeric PSI. The resulting PSI-NP assemblies were analyzed using a combination of X-ray energy-dispersive spectroscopy (XEDS), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), small-angle X-ray scattering (SAXS), and high-energy X-ray scattering with atomic pair distribution function (PDF) analyses. The results show that the PSI-supported NPs are approximately 1.8 nm diameter disk-shaped particles that assemble at discrete sites with 145 Å separation. This separation is too large to be consistent with NP nucleation and growth at a site adjacent to the F B cofactor site. Instead, we suggest a mechanism for NP growth at hydrophobic sites on the PSI stromal surface. The NPs photoreductively assembled on the PSI stromal surface are found to be analogous to the nanostructures produced by successive cycles of atomic layer deposition (ALD) of platinum onto 40 nm porous anodic alumina oxide supports, although the mechanisms for nucleation appear to differ. In conclusion, this work establishes a foundation for the investigation of the reductive assembly of abiotic metal catalysts at sites connected to photochemically reducing equivalent production in PSI.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Gating Single Molecules with Counterions

We report atomic-scale gating and visualization of local charge distribution within individual rare-earth-based molecular complexes on a metallic surface. The complexes are formed by a positively charged lanthanum ion coordinated to a (pcam)3 molecule and a negatively charged counterion trapped underneath via electrostatic interactions on a Au(111) surface. Local gating is performed by adding an additional negatively charged counterion to one side of the complex, which results in the redistribution of charges within the complex and a positive shift of the frontier orbitals. This is caused by the internal Stark effect induced by the added counterion. This effect is directly captured using tunneling spectroscopy and spectroscopic mapping at 5 K substrate temperature. The polarizability of the complex is corroborated by density functional theory and analytical calculations based on experimental findings. Furthermore, the influence of charge polarization on nearby complexes is investigated in a cluster purposely assembled using three complexes, which reveals maintaining the charge states as in single complexes. These findings will enable the design of robust charged rare-earth complexes to be tailored for potential solid-state applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Spatial Composition Influenced by Solvent in High-Entropy Alloy Nanoparticle Synthesis via Polyol Reduction

The performance of nanoparticles in catalytic reactions depends critically on their surface composition. In a multielemental system, this issue becomes even more important. Here, we report that the choice of solvent in polyol reduction synthesis of high entropy alloy (HEA) nanoparticles can have a subtle but significant influence on the elemental distribution near the surface of individual nanoparticles. Our study reveals that longchain polyethylene glycol typically produces a more uniform multielement distribution within a nanoparticle than short-chain triethylene glycol under identical experimental conditions. We performed electrochemical reduction of metal salts in both solvents to understand the reduction kinetics of metal salts, which shows that a solvent capable of improving the co-reduction of metal salts leads to the synthesis of more homogenized nanoparticles, whereas a solvent with a varying degree of reduction potency will lead to inhomogeneous elemental distribution in an HEA nanoparticle.

Catalyst↗

DOE OSTI2025

Sustainable Triacetic Acid Lactone Production from Sugarcane by Fermentation and Crystallization

Triacetic acid lactone (TAL) has the potential to serve as a bioderived platform chemical for commercial products including sorbic acid and recyclable polydiketoenamine plastics. In this study, we leveraged BioSTEAM to design, simulate, and evaluate (via techno-economic analysis, TEA, and life cycle assessment, LCA) TAL production from sugarcane. We experimentally characterized TAL solubility, calibrated solubility models, and designed a process to separate TAL from fermentation broths by crystallization. The biorefinery could produce TAL at a minimum product selling price (MPSP) of $\$3.73$–5.86·kg –1 (5th–95th percentiles; baseline at $\$4.60$·kg –1 ) and a carbon intensity (CI) of 5.31 [2.60–8.71] kg CO 2 -eq·kg –1 , which could enable financially viable, low-CI production of sorbic acid and polydiketoenamines. To drive down costs and CI, we explored the theoretical fermentation space (titer, yield, productivity combinations), operation scheduling and capacity expansion strategies (e.g., integrated sorghum processing), and potential separation improvements (mitigating TAL loss through pH control). Advancements in key design and technological parameters could further reduce MPSP by 51% to $\$2.26$·kg –1 [$\$1.97$–2.80·kg –1 ] and CI by 43% to 3.05 [1.91–4.15] kg CO 2 -eq·kg –1 . This research highlights the ability of agile TEA-LCA to screen promising designs, navigate sustainability trade-offs, prioritize research needs, and chart quantitative roadmaps to advance bioproducts and biofuels.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Water Clustering Modulates Activity and Enables Hydrogenated Product Formation during Carbon Monoxide Electroreduction in Aprotic Media

Water solvation plays a critical role in a wide range of electrochemical transformations, but its role is often convoluted since water is typically used as both a solvent and a proton source. Here, we experimentally control water speciation and activity using aprotic solvent media during the carbon monoxide reduction reaction (CORR). Remarkably, we show that aprotic solvents that support microheterogeneous water–water clusters lead to significant amounts of CORR products (methane and ethylene) with a maximum ethylene Faradaic efficiency of 22% in acetonitrile (χ H 2 O = 0.2). In contrast, microhomogeneous systems–where water integrates into the solvents’ intermolecular binding network and has lower activity–primarily support the undesired hydrogen evolution reaction (HER). As a result, insights gained expand our understanding of water activity and nonaqueous electrolyte design for other important transformation reactions beyond CO reduction, such as CO2RR and HER.

Electrolytes↗

DOE OSTI2024

Cooperative Atomically Dispersed Fe–N 4 and Sn–N x Moieties for Durable and More Active Oxygen Electroreduction in Fuel Cells

One grand challenge for deploying porous carbons with embedded metal–nitrogen–carbon (M–N–C) moieties as platinum group metal (PGM)-free electrocatalysts in proton-exchange membrane fuel cells is their fast degradation and inferior activity. Here, we report the modulation of the local environment at Fe–N 4 sites via the application of atomic Sn–N x sites for simultaneously improved durability and activity. We discovered that Sn–N x sites not only promote the formation of the more stable D2 FeN 4 C 10 sites but also invoke a unique D3 SnN x –Fe II N 4 site that is characterized by having atomically dispersed bridged Sn–N x and Fe–N 4 . This new D3 site exhibits significantly improved stability against demetalation and several times higher turnover frequency for the oxygen reduction reaction (ORR) due to the shift of the reaction pathway from a single-site associative mechanism to a dual-site dissociative mechanism with the adjacent Sn site facilitating a lower overpotential cleavage of the O–O bond. This mechanism bypasses the formation of the otherwise inevitable intermediate that is responsible for demetalation, where two hydroxyl intermediates bind to one Fe site. Lastly, a mesoporous Fe/Sn-PNC catalyst exhibits a positively shifted ORR half-wave potential and more than 50% lower peroxide formation. This, in combination with the stable D3 site and enriched D2 Fe sites, significantly enhanced the catalyst’s durability as demonstrated in membrane electrode assemblies using complementary accelerated durability testing protocols.

36 MATERIALS SCIENCE↗

DOE OSTI2025

Dissolved Oxygen Redox as the Source of Hydrogen Peroxide and Hydroxyl Radical in Sonicated Emulsive Water Microdroplets

Sonicated emulsive water microdroplets (SEWMs) accelerate and enable a variety of catalyst-free chemical transformations. However, significant unanswered questions remain regarding the chemical intermediates they form and their possible redox origin. In this study, we identified dissolved O 2 as the primary originator of reactive oxygen species (ROS) such as OH• and H 2 O 2. We uncovered the role of dissolved O 2 redox by using a combination of microelectrochemical methods to detect H 2 O 2 , isotopic methods to identify the source of H 2 O 2 , and a combination of electron spin resonance and the DMPO spin trap to detect radicals such as OH•. Notably, we found that H 2 O 2 production is correlated with O 2 content via a reduction pathway enabled by a sufficiently large reducing power that can additionally generate H 2 and even perform Pb electroless deposition on Au and Cu metal substrates. Building on our findings, continuous O 2 bubbling of SEWMs showed accumulation of H 2 O 2 up to ∼88 mM in the aqueous phase within 1 h of sonication, demonstrating the scale-up promise of this method. Distinct to sonochemistry of a single phase, this study advances our understanding of the confluence of redox and chemical reaction mechanisms within SEWMs as a biphasic system. This insight paves the way for improving their reaction kinetics, yield, and selectivity, positioning these attractive redox microreactors as alternatives to traditional electrolyzers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Deciphering Catalyst–Support Interaction via Doping for Highly Active and Durable Oxygen Evolution Catalysis

The design of oxygen evolution reaction (OER) electrocatalysts demands a delicate balance between activity and stability. Here, in this study, we present a rational design approach that leverages catalyst-support interactions to enhance both the intrinsic activity and durability of Ir-based catalysts. Our study reveals that while Mo doping energetically promotes the formation of high-valent Ir species, enhancing intrinsic catalytic activity, it also leads to a reduction in electrical conductivity. These findings emphasize that supporting doping can introduce both beneficial and limiting effects, highlighting the need for a carefully balanced design strategy to optimize the overall OER performance. Simultaneously, in situ analytical techniques and comparative evaluation reveal the crucial role of oxide supports in stabilizing the catalyst. These findings highlight the pivotal role of interface engineering in maintaining catalyst integrity and the need for support materials that balance dopant-driven electronic promotion with structural and electrochemical robustness. These interconnected degradation pathways highlight the need to move beyond a catalyst-centric view and instead adopt a system-level understanding of the stability. Our approach offers a strong foundation for the rational design and evaluation of high-performance OER electrocatalysts for electrochemical energy applications.

Kim, Jinyeop [Korea Advanced Inst. Science and Tec↗

DOE OSTI2025

Reticular Structural Diversification of Zirconium Metal–Organic Frameworks Through Angular Ligand Configuration Control

Reticular chemistry offers practical guidelines for enlarging and enriching the arsenal of metal–organic frameworks (MOFs). However, reticular expansion to access mesoporous structures remains challenging due to limitations in achieving precise control over both the size and configuration during building units’ extension. Herein, we combine ligand isomerization and functionalization strategies to regulate the ligand configuration by systematically replacing aryl C–H groups with N atoms, resulting in angular dicarboxylate ligands with various symmetries. The assembly between a 4,4′-(pyridine-2,6-diyl)dibenzoic acid ligand (1N, C 2 symmetry) and 12-connected Zr 6 cluster leads to the formation of a pseudo ftw topology framework (NU-2611), where one pair of nose-to-nose 1N ligands resembles a tetra-topic ligand. When a 6,6′-(1,3-phenylene)dinicotinic acid ligand (2N, C S symmetry) was used, another pseudo ftw network NU-2612 was obtained with a 2-fold framework interpenetration. Interestingly, the planar [2,2′:6′,2″-terpyridine]-5,5″-dicarboxylic acid ligand (3N, C 2V symmetry) yielded an intriguing mesoporous Zr-MOF with kag topology. NU-2613 represents the first example of kag Zr-MOF designed to include large, well-defined mesopores. The diversity of these MOFs was further enhanced through post-synthetic metalation of linkers. Particularly, metalation of the chelating 3N ligand with Fe 3+ in NU-2613 enables efficient catalytic transformation within the functionalized channels. This work contributes insight into the reticular expansion of Zr-MOFs by finely-tuning the ligand planarity, advancing the structure diversification of mesoporous frameworks for specific applications.

Cluster chemistry↗

DOE OSTI2025

Photosynthetic Biohybrid System for Enhanced Abiotic N 2 -to-NH 3 Conversion under Ambient Conditions

Photosynthetic biohybrid systems (PBSs) offer an eco-friendly approach to transforming solar energy into value-added products by integrating biological entities with inorganic semiconductors. However, the chemical conversion capacity of most PBSs has inherent limitations, as whole-cell bacteria and isolated enzymes require fine-tuning of environmental conditions. Here, in this study, we report a new PBS developed by introducing free-standing ceria nanoparticles into the purple membrane (PM) of Halobacterium salinarum archaea, which can unidirectionally transfer charge carriers in response to incident photons, even after separation from living archaea at various conditions. Our microscopy, spectroscopy, and synchrotron X-ray scattering analyses confirm that the electrostatic assembly between ceria and PM creates seamless interfacial contact, thereby enhancing the photocatalytic capacity of ceria. Although the conversion of dinitrogen (N 2 ) to ammonia (NH 3 ) is thermodynamically challenging due to the triple bond in N 2 and a series of charge-transfer reactions, our PM–ceria (PMC) hybrid nanoparticle efficiently produces NH 3 by reducing N 2 using solar energy even under atmospheric pressure and room temperature while simultaneously converting glycerol into value-added derivatives. Additionally, our PMC nanoparticle involves neither toxic/precious metals nor bioengineering processes to achieve enhanced photocatalytic N 2 -to-NH 3 conversion. This study sheds light on the new aspect of PBSs by employing PM to potentially resolve the global energy and environmental challenges posed by the conventional Haber–Bosch process.

Jang, Jinhyeong [Argonne National Laboratory (ANL)↗

DOE OSTI2025

Customizable Aperture Geometry in Metal–Organic Frameworks for Kinetic Hydrocarbon Separation

Precise control of aperture dimensions is crucial in adsorptive separations of hydrocarbons, as it directly affects key parameters such as selectivity, capacity, diffusion, and recyclability. The development of metal–organic frameworks (MOFs) has enabled the fine-tuning of local pore environments to address important hydrocarbon separations. However, customizing the aperture geometry to tune the kinetic separation performance remains challenging. Here, we deploy a mixed-linker synthesis strategy, combining long and short linkers on fcu net Zr-MOFs with equilateral triangular apertures to construct isoreticular multivariate MOFs, NU-415 and NU-416, with tailored isosceles triangular apertures suitable for the separation of hexane isomers. Sorption, liquid batch separation, and X-ray diffraction measurements demonstrate significantly improved selectivity, capacity, stability, and recyclability of NU-415 and NU-416 compared with Zr-muconate and MOF-801. Notably, both NU-415 and NU-416 achieve uptake capacities of 2.2 mmol g –1 in 1 min with an n-hexane to 2,2-dimethylbutane selectivity over 200 in an equimolar ternary mixture at ambient conditions, comparable to leading reported materials. Mechanistic studies confirm that separation performance is predominantly governed by significant kinetic differences rather than by thermodynamics. Furthermore, the successful customization of aperture geometry not only enables superior linear to monobranched hexane selectivity in NU-415 but also demonstrates the mixed-linker synthesis strategy as a promising solution for precise and predictable pore architecture control in MOFs.

Adsorption↗