Jeff Foster, an Alvin M. Weinberg Fellow, earned his PhD from Virginia Tech. His dissertation focused on developing a methodology to leverage gaseotransmitters, specifically hydrogen sulfide, for human therapy. His work showed that hydrogen sulfide exhibits selective anticancer activity and may represent a promising alternative cancer therapy. Jeff’s mentor is Tomonori Saito, a chemist in the Chemical Sciences Division.
Working in the Soft Matter Group, Chemical Sciences Division, Jeff will focus his fellowship research on developing homogeneous, stimuli-responsive catalysts for precision polymer synthesis. His methodology will enable kinetic control over polymer sequence, providing a tool to create polymers with intentionally designed sequences. Fundamental sequence–structure–property relationships discovered during Jeff’s fellowship work will provide a framework for the design of future sustainable materials for packaging, construction, energy storage, and medicine. His ongoing research interests leverage a framework of synthetic methodology, homogeneous catalysis, and organic material science to uncover structure–property relationships, create novel materials with emergent functionality, and develop efficient and sustainable manufacturing processes.
Brenden Ortiz, a Eugene P. Wigner Fellow, earned his PhD in material science from the Colorado School of Mines in 2019. His dissertation focused on accelerating the discovery and optimization of thermoelectric materials by developing techniques that aimed to accelerate both the theoretical and experimental aspects of material science. Brenden’s work resulted in the discovery of a new family of metals, AV3Sb5 (A: K, Rb, Cs) materials, which show a unique new quasi-2D kagome lattice and exhibit superconductivity, a charge density wave, and potential nontrivial topology. The combination of these properties together on the kagome lattice had never been seen before. His study renewed interest in the examination of kagome metals by researchers around the world, with over 350 additional manuscripts being published on this family in the past 2 years. Brenden’s mentors are Michael McGuire and Andrew May, both R&D staff in the Materials Science and Technology Division.
Working in the Correlated Electron Materials Group, Brenden will focus his fellowship research on developing methods to control and predict the emergence of electronic instabilities in correlated metals. His project will facilitate the design of the next generation of quantum materials through a better understanding of the connection between the electronic structure of materials, the high-dimensional chemical space, and the emergence of correlated electron properties, such as superconductivity and charge density waves. Brenden’s ongoing research interests include the connection between chemistry and thermodynamics in complex materials. He is also interested in high-dimensional chemical spaces and how the influence over alloys, dopants, and defects can radically alter material properties.
Yue Yuan, an Alvin M. Weinberg Fellow, earned her PhD in fiber and polymer science and a graduate minor in biochemistry in 2021 from North Carolina State University. Her dissertation focused on the challenges existing in global management of carbon dioxide emissions and recent research on applying biocatalysts, as an alternative to high-energy and high-cost traditional liquid solvents in carbon dioxide scrubbing processes. Her work introduced a new category of material that has hierarchical structure and biocatalytic function. Her study also uncovered the mechanism of enhanced catalyzed reactions at liquid–gas–solid interfaces. Yue Yuan’s mentor is Dr. Rigoberto Advincula, group leader in the Macromolecular Nanomaterial Group at the Center for Nanophase Materials Sciences.
Yue Yuan will focus her fellowship research on renewable macromolecular nanomaterials, particularly how their charge and hydrophobicity impact their reassembly with additive manufacturing techniques, outside the biological system. Her ongoing research interests include working on advanced functional materials, particularly bioderived and bioinspired materials, and focusing on bridging fundamental bioscience discoveries with advanced materials manufacturing through revealing the mechanisms behind the phenomena we observed in material formation.
Marm Dixit, an Alvin M. Weinberg Fellow, earned his PhD from Vanderbilt University. His dissertation focused on investigating processing–structure–function relationships in solid-state batteries. Marm’s thesis provided insight into failure mechanisms for several prevalent material alternatives of solid electrolyte as well as design rationales for achieving improved performance of solid-state batteries. These pivotal material technologies will enable electrification of the transportation sector and provide affordable, high energy density (HED), durable, and safe energy storage. Marm’s mentor is Ilias Belharouak, Electrification and Energy Infrastructure section head in the Electrification and Energy Infrastructure Division.
Working in the Emerging and Solid-State Batteries Group, Electrification and Energy Infrastructures Division, Marm will focus his fellowship research on evaluating and understanding the fundamental behavior of novel solid electrolyte materials against metallic anodes and high-voltage cathodes to generate insights that can be leveraged into high-performance devices. He will also investigate the influence of component fabrication routes, device integration steps, and operation protocols on device performance to provide energy storage solutions with techno-economic feasibility. His project is expected to enable scalable production of HED solid-state batteries that significantly impact the mobility industry and help in the electrification of the sector. In fall 2021, Marm was awarded a Toyota Young Investigator Fellowship for Projects in Green Energy Technology from the Electrochemical Society. The fellowship provides funding for young scientists and engineers to pursue battery and fuel cell research with an emphasis on unique, innovative, or unconventional technical approaches and the feasibility of the technology to positively impact the field of green energy. His ongoing research interests include energy storage and conversion, electrochemistry, synchrotron/neutron science, imaging, heterogeneous catalysis, and big data and machine learning.
Addis Fuhr, an Alvin M. Weinberg Fellow, earned his PhD from the University of California–Los Angeles. His dissertation focused on elucidating the electronic, optical, and magnetic properties of defects in quantum dots, and theory–experiment matching. Ternary copper-based quantum dots have unusual physical properties, making it difficult to determine how to optimize them for different applications. He helped unravel the mysterious origins of their unusual electronic, optical, and magnetic properties by combining theory with experiment to reveal mechanisms for defect formation and corresponding physics. His research helped improve the performance of CuxIn2-xSeyS2-y quantum dots for applications such as solar windows, solar cells, field-effect transistors, and light-emitting diodes. Addis’s mentor is Bobby Sumpter, ORNL Corporate Fellow and Theory and Computation section head in the Center for Nanophase Materials Sciences (CNMS).
Working in the Nanomaterials Theory Institute in CNMS, Addis is researching ways to integrate machine learning with ab initio computational chemistry and experimental materials characterization methods to enrich our understanding of the chemistry and physics of heterogeneity and defects in materials and to accelerate the discovery of materials with specific, desired functionality. His project is expected to enable accelerated discovery and understanding of the physics and chemistry of defects and heterogeneity in complex materials for applications such as multiferroics, quantum materials, solar energy, and battery, refractory, or nuclear materials. Addis’s ongoing research interests include combining theory with experiment to understand structure–property relationships for defects, heterogeneity, and coexisting phases in materials. He also is interested broadly in using theory/artificial intelligence to predict experimental signatures, and aiding in the design of materials with target functionalities.
Jake Nichols, an Alvin M. Weinberg Fellow, earned his PhD from Princeton University. His dissertation focused on modeling the erosion, transport, and redeposition of wall materials in magnetic fusion devices that utilize multiple materials for plasma-facing components and examining how these materials temporally evolve into mixed-material surfaces. His thesis clarified the mechanisms that limit the lifetime of thin film–conditioning techniques that are frequently applied to the walls of magnetic fusion devices to control impurities. This understanding will allow for more targeted conditioning of the wall surfaces, enabling present fusion devices to operate at higher performance for a longer period of time between maintenance phases. Jake’s mentor is Zeke Unterberg, Power Exhaust and Particle Control group leader.
Working in the Power Exhaust and Particle Control Group, Fusion Energy Division, Jake will focus his fellowship research on developing novel models for filamentary plasma transport in the edge of magnetic fusion devices that incorporate advanced divertor regimes and realistic 3D wall geometries, helping to constrain estimates of the heat and particle fluxes that will strike different parts of the vessel wall in a pilot plant–scale fusion device. His project is expected to advance optimization of the main wall of a fusion reactor by shaping the wall geometry such that the strongest fluxes are concentrated on components designed for the task. This approach will improve component reliability while reducing overall reactor cost. Jake’s ongoing research interests include plasma–material interactions, tokamak edge and divertor plasma physics, and integrated modeling of fusion systems.
Alice Perrin, an Alvin M. Weinberg Fellow, earned her PhD from Carnegie Mellon University. Her dissertation focused on the characterization of high-entropy alloys for magnetocaloric applications. Alice developed the first high-entropy alloy studied for magnetocaloric properties and demonstrated that the distribution of magnetic exchange interactions caused by the spread of dissimilar atoms on a single lattice favorably broadened the magnetocaloric response. Alice’s mentor is Ying Yang, a research scientist in the Materials Science and Technology Division.
Working in the Microstructural Evolution Modeling Group, Materials Science and Technology Division, Alice will focus her fellowship research on studying the effects of irradiation on grain boundary segregating nanocrystalline alloys; typically, solute segregation in nuclear materials reduces ductility and leads to embrittlement, but materials stabilized by high segregation energies that lead to equilibrium microstructures in which solutes decorate grain boundaries by design have not been studied for radiation tolerance. The small, thermodynamically stabilized nanocrystalline grain size of these alloys should increase their radiation tolerance due to the large area of grain boundaries that act as defect sinks. Her work will focus on understanding the segregated solutes’ behavior under irradiation and the resulting changes in microstructure and grain size, phase stability, and radiation hardening in this class of alloys. This research will potentially open up a new avenue of radiation-tolerant alloy design that takes advantage of new types of microstructures that utilize solute segregation as a feature instead of a bug. Alice’s ongoing research interests include nonequilibrium processing, thermodynamic and kinetic stabilization of metallic microstructures, functional alloy design for radiation resistance, and electrical and magnetic properties; additive manufacturing; and high-entropy alloys.
Bryan Piatkowski, a Liane B. Russell Fellow, earned his PhD from Duke University. His dissertation focused on the evolution and ecology of Sphagnum peat mosses, a group of plants that have extraordinary impact on global carbon cycling and engineer peatland ecosystems through traits such as cell wall biochemistry. Bryan’s thesis documented how functional traits evolved in Sphagnum and demonstrated the role of natural selection in shaping patterns of variation among species. Bryan’s mentor is Dave Weston, a staff scientist in the Biosciences Division.
Working with the Plant Systems Biology Group, Biosciences Division, Bryan will use evolutionary techniques to better understand how plants respond to challenging environmental conditions and identify the genetic components of stress tolerance that are shared across levels of biological hierarchy. Bryan’s project is expected to produce a comparative framework to integrate genetic discoveries from disparate model organisms and facilitate the translation of such findings into novel systems. He will also establish new capabilities to model the evolution of gene-to-trait associations and study how plants interact with their environment. Bryan’s ongoing research interests include understanding how organismal complexity emerges from genetic variation and linking microevolutionary processes, such as mutation, to macroevolutionary consequences like speciation.
Logan Sturm, an Alvin M. Weinberg Fellow, earned his PhD from Virginia Tech. His dissertation focused on cyber-physical security for additive manufacturing systems. Logan’s thesis provided a framework for identifying and mitigating sabotage attacks on additively manufactured parts using in situ monitoring, new techniques for securely transmitting part quality information to air-gapped side-channel monitoring systems, and an impedance-based method of nondestructively evaluating additively manufactured parts for defects. Logan’s mentor is Mason Rice, Resilient Complex Systems section head in the Cyber Resilience and Intelligence Division.
Working in the Embedded Systems Security Group, Cyber Resilience and Intelligence Division, Logan will focus his fellowship research on identifying cybersecurity vulnerabilities in additive manufacturing systems and developing techniques and platforms to mitigate the vulnerabilities. His work will include evaluating in‑process monitoring systems for metal laser powder bed fusion in an adversarial setting, developing new methods for improving the robustness of these systems to attacks, and investigating human factors and training to improve awareness and understanding of cybersecurity threats in manufacturing. Logan’s project is expected to provide improved security for manufacturing systems and increased awareness of the threats facing modern digital manufacturing. Logan’s ongoing research interests include in situ monitoring for additive manufacturing systems, vulnerability assessment in advanced manufacturing, data analytics for malicious defect detection, secure distributed manufacturing, unclonable security features for anticounterfeiting, and human–machine interactions in a cybersecurity context.
Trevor Aguirre, an Alvin M. Weinberg Fellow, earned his PhD from Colorado State University. His dissertation focused on investigating the architecture of biomechanically adapted unique porous bone architectures, including the trabecular architecture in the hind limbs of extant (e.g., elephant, rhinoceros) and extinct (mammoth and dinosaur) animals with large body mass, as well as the velar bone in Rocky Mountain Bighorn sheep horns. Trevor’s master’s degree focused on ceramics and ceramics processing. Understanding bone mechanics has informed his work engineering strong, lightweight structures, and his knowledge of ceramics is a natural fit with additive manufacturing. His mentor is Vlastimil Kunc, Advanced Composites Manufacturing group leader in the Manufacturing Science Division.
Working in the Advanced Composites Manufacturing Group, Manufacturing Science Division, Trevor will focus his fellowship research on additive manufacturing of high-performance ceramics composed of refractory and ultrahigh-temperature ceramic materials and processing effects on microstructure, mechanical, thermal, and thermomechanical performance for use in power generation. His work is expected to develop novel processing techniques compatible with additive manufacturing to produce ceramic heat exchanger materials that will increase energy conversion efficiency in power generation processes. Trevor’s ongoing research interests include understanding how the microstructures of additively manufactured ceramics can be tailored to withstand harsh environments necessary for efficient power generation.
Andrea Delgado, a Eugene P. Wigner Fellow, earned her PhD from Texas A&M University. Her dissertation focused on proving/disproving the existence of a particle not contained in the standard model of particle physics through the analysis of data collected by the Compact Muon Solenoid experiment at CERN, the European Organization for Nuclear Research, in Switzerland. The existence of such a particle would help alleviate discrepancies in results produced by the Large Hadron Collider beauty (LHCb) experiment, also at CERN. Andrea’s research at ORNL is interdisciplinary, focused on the intersection of quantum computing and particle physics. Her mentor is Marcel Demarteau, Physics Division director.
Working in the Nuclear Structure and Nuclear Astrophysics Group, Physics Division, Andrea will focus her fellowship research on quantum computing applications to high-energy physics. This work combines a scientific interest in extending our knowledge of the fundamental blocks of the universe and how they interact with each other and building better tools to analyze the data from large-scale particle physics experiments such as the LHC. Andrea’s research interests include developing data analysis tools for high-energy physics experiments, including machine learning and quantum computing. Andrea was a National Science Foundation Graduate Research Fellow and a National GEM Fellow at Fermi National Accelerator Laboratory before becoming a Distinguished Staff Fellow.
Stephen Taller, an Alvin M. Weinberg Fellow, earned his PhD from the University of Michigan. His dissertation focused on how accelerated damage rate experiments in the laboratory can capture the relevant processes that occur in structural materials in a nuclear reactor. Stephen used multiple ion beams simultaneously bombarding a target as a source of radiation damage at a rate 1,000× higher than test reactors to isolate the roles of temperature, damage rate, and helium co-generation rate in the nucleation of cavities that lead to the life-limiting degradation mode of irradiation-induced swelling. His work also involved developing a physical model to speculate where helium resides in the microstructure of ferritic-martensitic steel after irradiation. His mentor is Christian Petrie, Advanced Fuel Fabrication and Instrumentation group leader in the Nuclear Energy and Fuel Cycle Division.
Working in the Advanced Fuel Fabrication and Instrumentation Group, Nuclear Energy and Fuel Cycle Division, Stephen generates methods to shorten the development cycle of new materials for service with nuclear technologies. His work aims to bring the test and learn phases of materials evaluation in line with recent improvements in the design and manufacture phases. Stephen also focuses on the development and application of techniques for automating microscopy data acquisition and using machine learning to enhance the understanding of the relationships between the radiation-damaged microstructure observed at the nanoscale and their macroscale mechanical properties. The techniques developed will help reduce the time spent on postirradiation examination to increase the amount of knowledge gained per design cycle. Stephen’s ongoing research interests include understanding the life-limiting processes in materials for nuclear power reactor designs and how the microstructure of a material can be tailored to withstand the high temperatures and intense radiation fields expected in advanced reactors.
Andrew Ullman, a Eugene P. Wigner Fellow, earned his PhD from Harvard University. His dissertation focused on polynuclear cobalt complexes as models of a cobalt-based water oxidation catalyst. Using molecules to study structural and electronic analogs of an amorphous cobalt-oxide catalyst, he provided atomic-level insight into the mechanism of water oxidation at neutral pH, specifically pertaining to the contribution of the anionic electrolyte species beyond their role as proton acceptors. This work provided the understanding needed to further optimize the activity of metal-oxide–based water oxidation catalysts in neutral pHs. Andrew’s mentor is Robert Sacci, Energy Storage and Conversion interim group leader in the Chemical Sciences Division.
Working in the Energy Storage Group, Chemical Sciences Division, Andrew’s fellowship research will introduce a new type of solid-state electrolyte to the battery research field that has high single-ion conductivity, forms a stable interface with lithium metal anodes, enables uniform stripping and plating of lithium, and ultimately, is incorporated into a high-energy, inherently safe, solid-state battery. Such batteries have the potential to revolutionize the future of electro-mobility. Andrew’s ongoing research interests include applying synthetic chemistry to problems related to the movement of electrons (i.e., quantum particles) and ions (i.e., classical particles), which span the fields of energy storage, batteries, catalysis, and quantum information systems. He held a postdoc position at Sandia National Laboratories and developed battery separator coating materials for lithium ion and lithium metal batteries at battery start-up Sepion Technologies.