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DOE OSTI2025

Catching Fullerenes: Synthesis of Molecular Nanogloves

Abstract Herein, we report the synthesis of a new series of rigid, all meta ‐phenylene, conjugated deep‐cavity molecules, displaying high binding affinity towards buckyballs. A facile synthetic approach with an overall combined yield of approximately 53% in the last two steps has been developed using a templating strategy that combines the general structure of resorcin[4]arene and [12]cyclo‐ meta ‐phenylene. These two moieties are covalently linked via four acetal bonds, resulting in a glove‐like architecture. 1 H NMR titration experiments reveal fullerene binding affinities ( K a ) exceeding ≥10 6 M −1 . The size complementarity between fullerenes and these scaffolds maximizes CH⋯π and π⋯π interactions, and their host:guest adduct resembles a ball in a glove, hence their name as nanogloves. Fullerene recognition is tested by suspending carbon soot in a solution of nanoglove in 1,1,2,2‐tetrachloroethane, where more than a dozen fullerenes are observed, ranging from C 60 to C 96 .

Mirzaei, Saber [Department of Chemistry Rice Unive↗

DOE OSTI2025

Tubular Nanostructures from Large‐Pore 2D Covalent Organic Frameworks

Abstract The synthesis of a wavy mesoporous 2D covalent organic framework (COF) with a 6‐nm hexagonal pore lattice ( Joa‐COF‐1 ) is reported. This has been achieved by the synthesis of a terpyrenyl linker of approximately 2.7 nm in length and its subsequent condensation with a 3‐connected non‐planar cata‐hexabenzocoronene. Joa‐COF‐1 exists as non‐covalent tubular domains composed of π‐stacked 4 to 5 pores in 2D COF sections that can be separated by mild sonication, resulting in a family of tubular COF nanostructures that combine a 1D morphology with accessible mesopores.

Almarza, Joaquín [POLYMAT University of the Basque↗

DOE OSTI2025

Li 21 Ge 8 P 3 S 34 : New Lithium Superionic Conductor with Unprecedented Structural Type

Abstract Lithium superionic conductors are pivotal for enabling all‐solid‐state batteries, which aim to replace liquid electrolytes and enhance safety. Herein, we report the discovery of an unprecedented lithium superionic conductor, Li 21 Ge 8 P 3 S 34 , featuring a novel structural type and a new composition in the Li–Ge–P–S system. This material exhibits high lithium ionic conductivity of approximately 1.0 mS cm −1 at 303 K with a low activation energy of 0.20(1) eV. It's unique crystal structure was elucidated using three‐dimensional electron diffraction (3D ED) and further refined through combined powder X‐ray and neutron diffraction analyses. The structure consists of alternating two‐dimensional slabs: one of corner‐sharing GeS 4 tetrahedra and the other of isolated PS 4 tetrahedra, enabling efficient lithium‐ion transport through a tetrahedrally interconnected network of 1D, 2D, and 3D diffusion pathways. This distinctive structural motif provides a novel design strategy for next‐generation solid electrolytes, broadening the structural landscape of lithium superionic conductors. With further advancements in compositional tuning and interfacial engineering, Li 21 Ge 8 P 3 S 34 could contribute to the development of high‐performance all‐solid‐state batteries.

Chemistry↗

DOE OSTI2025

Tubular Nanostructures from Large‐Pore 2D Covalent Organic Frameworks

Almarza, Joaquín [POLYMAT University of the Basque↗

DOE OSTI2025

A Thorough Characterization of the Tellurocyanate Anion

Tellurocyanate, [TeCN] − , is the heaviest group 16 congener of the cyanate anion, [OCN] − . Due to the relative instability of the C─Te bond, tellurocyanate chemistry has seen only scarce attention. Here, we present the facile synthesis and thorough characterization of [K@crypt-222][TeCN]. The anion is essentially linear with interatomic distances C─N = 1.150(6)Å and C─Te = 2.051(4)Å, thus approximating a C≡N triple bond and for C─Te a bond order between 1 and 2. Fully 13 C and 15 N labeled [Te 13 C 15 N] − allowed for the extraction of chemical shifts and all possible coupling constants ( 13 C = 77.8 ppm, 15 N = 285.7 ppm, 125 Te = −566 ppm, 1 J 13C-15N = 8 Hz, 1 J 13C-125Te = 748 Hz, 2 J1 5N-125Te = 55 Hz), which were also determined independently by quantum chemical calculations. In the series [ChCN] − (Ch = O─Te), [TeCN] − shows the strongest spin-orbit coupling (SOC) induced heavy-atom effect on the light-atom shielding (SO-HALA-effect). In contrast, 15 N shifts are also well described without considering relativistic effects and/or SOC. Negative-ion photoelectron spectroscopy was used to extract the electron affinity (EA = 3.034 eV) and spin-orbit splitting (3807 cm −1 ) of [TeCN] • . These values continue the trends of falling EA and rising SOC in the series [ChCN] • .

Bonding analysis↗

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 OSTI2024

Hijacking a rapid and scalable metagenomic method reveals subgenome dynamics and evolution in polyploid plants

Premise: The genomes of polyploid plants archive the evolutionary events leading to their present forms. However, plant polyploid genomes present numerous hurdles to the genome comparison algorithms for classification of polyploid types and exploring genome dynamics. Methods: Here, the problem of intra- and inter-genome comparison for examining polyploid genomes is reframed as a metagenomic problem, enabling the use of the rapid and scalable MinHashing approach. To determine how types of polyploidy are described by this metagenomic approach, plant genomes were examined from across the polyploid spectrum for both k-mer composition and frequency with a range of k-mer sizes. In this approach, no subgenome-specific k-mers are identified; rather, whole-chromosome k-mer subspaces were utilized. Results: Given chromosome-scale genome assemblies with sufficient subgenome-specific repetitive element content, literature-verified subgenomic and genomic evolutionary relationships were revealed, including distinguishing auto- from allopolyploidy and putative progenitor genome assignment. The sequences responsible were the rapidly evolving landscape of transposable elements. An investigation into the MinHashing parameters revealed that the downsampled k-mer space (genomic signatures) produced excellent approximations of sequence similarity. Furthermore, the clustering approach used for comparison of the genomic signatures is scrutinized to ensure applicability of the metagenomics-based method. Discussion: The easily implementable and highly computationally efficient MinHashing-based sequence comparison strategy enables comparative subgenomics and genomics for large and complex polyploid plant genomes. Such comparisons provide evidence for polyploidy-type subgenomic assignments. In cases where subgenome-specific repeat signal may not be adequate given a chromosomes' global k-mer profile, alternative methods that are more specific but more computationally complex outperform this approach.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2024

Scale sensitivity of ethanol production via consolidated bioprocessing with consideration of feedstock cost

We examine feedstock cost and minimum selling price for ethanol production from corn stover as a function of scale, stover yield, participation rate, and price incentives for two conversion technologies: a conventional base case featuring thermochemical pretreatment with added cellulase, and an advanced case featuring consolidated bioprocessing with cotreatment (C-CBP). Delivered feedstock cost ranged from $\$85$ Mg −1 at small (10 million gallons year −1 or ~38 million L year −1 ) scale with high yield and participation rates to $\$124$ Mg −1 at large scale (60 million gallons year −1 or 227 million L year −1 ) and low yield and participation rates. The minimum ethanol selling price (MESP) was approximately twofold lower for the advanced case compared with the base case. The payback period was several times lower for the advanced case compared with the base case, with increasing disparity at smaller scales, and was highly sensitive to ethanol price supports. For both C-CBP and the conventional processing paradigm, MESP decreased with increasing scale, indicating that the cost penalty due to higher feedstock transport distances was more than outweighed by lower capital costs. However, the cost penalty for operation at small scale, expressed in $ gallon −1 ethanol, is lower for C-CBP than for the conventional paradigm by roughly twofold. Particularly for initial applications of C-CBP, we speculate that this cost penalty will likely be modest compared with the anticipated benefits of small-scale operation such as increased opportunity to use existing infrastructure, easier plant siting and supply chain establishment, and lower total investment required.

biorefinery scale↗

DOE OSTI2025

Bio‐Inspired In Situ Tuning of the Hydrophobic Environment Around Catalytically Active Organic Ligand‐Stabilized Ruthenium Nanoparticles

Abstract The organic ligand environment surrounding enzymatic and homogeneous catalytic active sites often determines catalytic activity. Ruthenium nanoparticles, ≤1 nm in diameter, are synthesized using monodentate thiol, monodentate phosphine, and bidentate bisphosphine ligands. Even though some of the ruthenium surface is blocked by the ligands, catalytic activity is still observed for CO oxidation and H 2 O 2 decomposition. All three ligand‐stabilized ruthenium nanoparticles have similar CO oxidation rates; however, the bisphosphine‐stabilized Ru nanoparticles are approximately 2.5 times less active than the monothiol‐stabilized and monophosphine‐stabilized ruthenium nanoparticles for H 2 O 2 decomposition. It is observed that the organic ligand environment is modulated in situ during nanoparticle synthesis via partial oxidation of the bisphosphine as confirmed by 31 P NMR measurements. We hypothesize that bisphosphine‐bound Ru nanoparticles consist of a Ru core with some of the ligands bound in a monodentate manner where the other P atom is oxidized and not bound to the Ru surface leading to a thicker hydrophobic layer around the Ru nanoparticles. The increase in hydrophobicity is confirmed via contact angle and zeta potential measurements. H 2 O 2 decomposition rates are known to decrease with increasing hydrophobicity, and this work illustrates a pathway for increasing hydrophobicity in situ using ligand‐bound metallic nanoparticles.

Sufyan, Sayed Abu [Department of Chemical Engineer↗

DOE OSTI2026

Coordination of Anle138b to Silver Results in Selective Reduction of a C-terminal truncated Alpha-synuclein Protein and Increased Aggregate Size

Parkinson’s disease (PD) is a prevalent age-related neurodegenerative syndrome, partially thought to be caused by a decrease in alpha-synuclein proteostasis. Anle138b = 5-(1,3-benzodioxol-5-yl)-3-(3-bromophenyl)-1H-pyrazole (HL), is undergoing clinical trials as a promising mitigator of alpha-synuclein aggregation. Because complexation to metals is known to modulate the activity of several drugs, we have prepared and characterized: H2L(ClO4), [CuI(µ-L)]3, and [AgI(µ-L)]3. To better understand the bioviability of these compounds, we monitored their effects in a cell culture model of alpha-synuclein protein aggregation using human alpha-synuclein pre-formed fibrils (PFFs). Using two different anti-alpha-synuclein antibodies, our data suggests that [AgI(µ-L)]3 decreases a C-terminal truncated protein that is approximately 12.4 kDa, as well as increases the size and alters the shape of PFF-induced aggregates. This indicates that [AgI(µ-L)]3 impacts aggregation in a manner different from HL and may serve as a novel tool for studying C-terminal truncation related aggregation chemistry.

Rue, Kelly L.↗

DOE OSTI2024

Early experiences evaluating the HPE/Cray ecosystem for AMD GPUs

Summary The Oak Ridge Leadership Computing Facility (OLCF) has a long history of supporting and promoting GPU‐accelerated computing starting with the deployment of the Titan supercomputer in 2021 and continuing with the Summit supercomputer which has a theoretical peak performance of approximately 200 petaflops. Because the majority of Summit's computational power comes from its 27,972 GPUs, users must port their applications to one of the supported programming models in order to make efficient use of the system. To prepare the transition to Frontier, the OLCF's exascale supercomputer, users will need to adapt to an entirely new ecosystem which will include new hardware and software technologies. First, users will need to familiarize themselves with the AMD Radeon GPU architecture. Furthermore, users who have been previously relying on CUDA will need to transition to the Heterogeneous‐Computing Interface for Portability (HIP) or one of the other supported programming models (e.g., OpenMP, OpenACC). In this work, we describe our initial experiences and lessons learned in porting three applications or proxy apps currently running on Summit to the HPE/Cray ecosystem to leverage the compute power from AMD GPUs: minisweep, GenASiS, and Sparkler. Each one is representative of current production workloads utilized at the OLCF, different programming languages, and different programming models.

Melesse Vergara, Verónica G.↗

DOE OSTI2024

Quantum optimization algorithms: Energetic implications

Since the dawn of quantum computing (QC), theoretical developments like Shor's algorithm proved the conceptual superiority of QC over traditional computing. However, such quantum supremacy claims are difficult to achieve in practice because of the technical challenges of realizing noiseless qubits. In the near future, QC applications will need to rely on noisy quantum devices that offload part of their work to classical devices. One way to achieve this is by using parameterized quantum circuits in optimization or even in machine learning tasks. The energy requirements of quantum algorithms have not yet been studied extensively. Here in this article, we explore several optimization algorithms using both theoretical insights and numerical experiments to understand their impact on energy consumption. Specifically, we highlight why and how algorithms like quantum natural gradient descent, simultaneous perturbation stochastic approximations or circuit learning methods, are at least 2x to 4x more energy efficient than their classical counterparts; why feedback-based quantum optimization is energy-inefficient; and how techniques like Rosalin can improve the energy efficiency of other algorithms by a factor of ≥2 0 x. Finally, we use the NchooseK high-level programming model to run optimization problems on both gate-based quantum computers and quantum annealers. Empirical data indicate that these optimization problems run faster, have better success rates, and consume less energy on quantum annealers than on their gate-based counterparts.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2025

Approaching the Lower Temporal Limit of Laser‐Produced Plasma Sources for Table‐Top Soft X‐Ray NEXAFS Measurements

Abstract The increasing popularity of time‐resolved X‐ray absorption measurements for understanding dynamics in molecular and material systems has led to many advances in table‐top sources for pulsed X‐rays. We report on a table‐top laser‐produced plasma (LPP) source that can perform soft X‐ray (SXR), near‐edge X‐ray absorption fine structure (NEXAFS) measurements using a laser source with 23 ps pulse duration. The spectrometer's key specifications, such as brilliance, resolution, and stability, are characterized against the more commonly used longer‐pulse‐duration LPP sources. The 23 ps laser produced approximately an order of magnitude weaker SXR flux than the 8 ns laser for a higher power density due to the smaller total energy absorbed by the plasma. The increased repetition rate, as well as the use of a high line‐density X‐grating, and a self‐referencing scheme still allowed for NEXAFS measurements of Si 3 N 4 and TiO 2 thin films with 2.5 minute acquisition times, a resolving power of E/ΔE=424, and a signal‐to‐noise ratio of 100. It was observed that degradation of the gas jet nozzle led to long‐term instability of the source, which can be remediated using alternative nozzle designs. This work demonstrates the feasibility of achieving higher temporal resolution in future time‐resolved X‐ray absorption measurements using table‐top LPP sources.

Nimlos, Danika [Division of Chemistry and Chemical↗

DOE OSTI2025

Identification and Clinical Evaluation of Potential Biomarkers for Breast Cancer Resistance Protein ( BCRP / ABCG2 )

Clinical inhibition and genetic variation of the Breast Cancer Resistance Protein (BCRP/ABCG2) efflux transporter can significantly influence drug exposure, highlighting the need for reliable BCRP functional biomarkers. This study aimed to identify and evaluate biomarkers predictive of BCRP function in humans. A comprehensive analysis of metabolomic genome‐wide association studies (mGWAS) was conducted to discover potential BCRP biomarkers, followed by evaluation inin vitrotransporter assays and a clinical drug–drug interaction (DDI) study. Across multiple mGWAS datasets, plasma concentrations of three herbicide derivatives—4‐hydroxychlorothalonil (4HC), 3‐bromo‐5‐chloro‐2,6‐dihydroxybenzoic acid (BCDBA), and 3,5‐dichloro‐2,6‐dihydroxybenzoic acid (DCDBA)—were significantly elevated (P < 5E‐8) in individuals carrying reduced functionABCG2polymorphisms. These compounds were confirmed as novel BCRP substrates via transporter uptake assays and selected for clinical evaluation alongside riboflavin, a known BCRP substrate and potential BCRP biomarker. In a DDI study with 11 healthy subjects, eltrombopag, a BCRP inhibitor, increased rosuvastatin concentrations by approximately twofold (P = 0.002). No significant changes in the plasma concentrations of organic anion transporting polypeptide 1B (OATP1B) biomarkers (CP‐I and CP‐III) or potential BCRP biomarkers (4HC, BCDBA, DCDBA, or riboflavin) were observed. Notably, two subjects were heterozygous carriers for theABCG2p.Q141K variant and exhibited significantly higher baseline concentrations of 4HC (P = 0.004) and BCDBA (P = 0.0003), consistent with reduced BCRP function. These findings suggest that 4HC and BCDBA are promising biomarkers for baseline BCRP function in specific populations, such as those harboring reduced function genetic polymorphisms, but do not appear suitable for detecting acute BCRP inhibition.

Pharmacology & Pharmacy↗

DOE OSTI2025

A Methodology for the Analysis of Water Oxidation Electrocatalysts in the Absence of Limiting Current that Avoids the Pitfalls of Existing Methods

Water oxidation is an important reaction studied as a way to generate electrons from water, to promote water splitting and the formation of green hydrogen. When using electrodes to drive homogeneous water oxidation catalysis, cyclic voltammograms are analyzed to provide catalytic rate constants. There are two main methods, foot-of-the-wave analysis (FOWA) and limiting current analysis. FOWA relies on approximations inherent to analyzing water oxidation catalysis, such as determining the formal potential of the catalytic intermediate, E 0 cat . Limiting current methods are the optimal way to analyze catalyst performance but rely on observable limiting current, which is virtually never seen in water oxidation. To avoid those issues, a method is proposed for analyzing nonideal cyclic voltammetry waveshapes in water oxidation: by analyzing rate data across a large range of potentials, an optimal potential, E 0 cat , can be obtained, where catalytic current, i cat , is nearly independent of scan rate and has a linear dependency on buffer concentration. Here, the method is applied to four homogeneous water oxidation catalysts with prior extensive electrochemical elucidation, all of which lack an ideal, purely kinetic waveshape in cyclic voltammetry. Application of the method avoids the biases of the other methods cited for the kinetic analyses of water oxidation catalysts.

14 SOLAR ENERGY↗

DOE OSTI2025

Chemically Recyclable Polyester Thermosets from Activated Adipic Acid and Renewable Polyols

This study outlines a method for producing chemically recyclable crosslinked polyesters using renewable polyols-glycerol and sorbitol-combined with adipic acid (AA), which is transformed/activated into a polyanhydride mixture prior to use. A three-step procedure has been designed: 1) an acid-catalyzed reaction of AA with nontoxic isopropenyl acetate or acetic anhydride to form a crosslinking mixture (CLM) made of adipic-acetic mixed polyanhydrides; 2) a solvent- and additive-free process where glycerol or sorbitol, or a combination thereof, is reacted with the CLM to achieve a prepolymer, and 3) a casting/molding of the liquid viscous prepolymer to yield a thermoset as the end product. Different thermosets (eight examples) are prepared by changing the reagents ratio. These solids are thoroughly characterized by tensile tests, DMA, high-resolution magic angle spinning and solid-state NMR, thermal gravimetric analysis, DSC, and fourier transformed infra red (FT-IR) spectroscopy. The formation of cross-linked polyesters is confirmed in all cases, but mechanical properties varied significantly from one specimen to another. Interestingly, a tensile strength up to 18 MPa-approximately an order of magnitude higher than similar polymers-is achieved when sorbitol and the CLM are used in a 1:1 wt% ratio. The chemical recycle of the resulting polymers is achieved via methanolysis with quantitative recovery of the monomeric units.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2026

California Trees Seasonally Use Augmented Water Sources: Water Isotope Tracking in a Groundwater‐Dependent Ecosystem

Sustainable groundwater management must account for the needs of groundwater dependent ecosystems. To understand the relationship of ecosystems and seasonal water use, we studied the stable isotope composition (δ 18 O and δ 2 H) of water in streamside trees in a semi-arid streamside environment (Livermore, California, USA). We sampled seven trees at two sites every other month from April 2024 through April 2025 for tree xylem stable water isotope signatures. These data were compared to potential source waters: precipitation, imported surface water, soil water and regional groundwaters. Large daily precipitation events were found to be isotopically similar to regional groundwater and were thus treated as one water source. A Bayesian mixing model using stable water isotopes was used to determine the ratios of these three potential source waters (small daily precipitation events, groundwater/large daily precipitation events and imported water) present in tree xylem water. On average, tree water sources include 32% imported water (SD = 9%), 35% small daily precipitation events (SD = 10%) and 33% groundwater (SD = 3%), with significant seasonal variation (t summer-winter = 30.8, p < 0.01), particularly drawing more imported water (more than 55%) in the summer. While small daily precipitation events contribute only 10% of the total precipitation in our dataset, it represents a third of water used by trees. In addition, while these ecosystems are designated as groundwater dependent ecosystems, the trees use approximately one third imported water and even more during dry summer months. This approach provides water managers with a practical tool for quantifying ecosystem water needs, supporting data-driven decisions and regulatory compliance. While California's Sustainable Groundwater Management Act emphasizes supporting groundwater dependent ecosystems, it allows flexibility in demonstrating benefits. In conclusion, our methodology provides a way to document that management actions (such as managed aquifer recharge with imported water) deliver measurable co-benefits to GDEs.

Geosciences↗

DOE OSTI2024

Designing Spin‐Crossover Systems to Enhance Thermopower and Thermoelectric Figure‐of‐Merit in Paramagnetic Materials

Thermoelectric materials, capable of converting temperature gradients into electrical power, have been traditionally limited by a trade‐off between thermopower and electrical conductivity. This study introduces a novel, broadly applicable approach that enhances both the spin‐driven thermopower and the thermoelectric figure‐of‐merit (zT) without compromising electrical conductivity, using temperature‐driven spin crossover. Our approach, supported by both theoretical and experimental evidence, is demonstrated through a case study of chromium doped‐manganese telluride, but is not confined to this material and can be extended to other magnetic materials. By introducing dopants to create a high crystal field and exploiting the entropy changes associated with temperature‐driven spin crossover, we achieved a significant increase in thermopower, by approximately 136 μV K −1 , representing more than a 200% enhancement at elevated temperatures within the paramagnetic domain. Our exploration of the bipolar semiconducting nature of these materials reveals that suppressing bipolar magnon/paramagnon‐drag thermopower is key to understanding and utilizing spin crossover‐driven thermopower. These findings, validated by inelastic neutron scattering, X‐ray photoemission spectroscopy, thermal transport, and energy conversion measurements, shed light on crucial material design parameters. We provide a comprehensive framework that analyzes the interplay between spin entropy, hopping transport, and magnon/paramagnon lifetimes, paving the way for the development of high‐performance spin‐driven thermoelectric materials.

magnons↗