- Issue 1 |
- August 2009
Double Feature: EFRCs
How many people have the opportunity to direct a brand new, multi-million dollar center? Forty-six, with a new energy initiative from the Department of Energy’s Office of Science. The initiative is establishing 46 Energy Frontier Research Centers (EFRCs) at universities, national laboratories, nonprofit organizations, and private institutions. These multi-million dollar centers are designed to use advanced scientific research to address current and future energy challenges. In addition, they will focus on training the next generation of scientists. ORNL was recently awarded 2 EFRCs, and is partnering on about 10 others. Competition was fierce - there were about 260 applicants overall - but the CDP and the FIRST Center rose to the top and are now underway. Both ORNL EFRCs, along with many of our partnerships, will be based in the Physical Sciences Directorate.
The Center for Defect Physics, or CDP, (short for Energy Frontier Center for Defect Physics in Structural Materials) brings together leading national and international researchers in materials science and experimental and theoretical physics to address the most fundamental challenges in structural materials for energy. It involves a total of 9 organizations, including both national laboratories and universities. Research in the CDP is focused on providing the fundamental knowledge to allow atomistic control and manipulation of defects, defect interactions, and defect dynamics.
So, why should we study material defects? “Crystals are like people: it is the defects in them that make them interesting.” This oft quoted quip of Sir Charles Frank speaks to the very heart of structural alloys. Indeed, the extent to which the collective effects of defects can be manipulated and controlled yields the combination of structural materials properties that underpin nearly all of our energy and transportation technologies. In counterpoint, it is also clear that bounds on performance of current structural materials result from limitations in our understanding of defects. Indeed, performance limits are rarely the result of insurmountable physical principles, thus leaving open the possibility that increased understanding of defects will result in new materials with substantially improved properties – with consequent impacts on energy production and usage. When materials are exposed to extreme environments or pushed to extremes of temperature and stress, it is the defects’ response – both preexisting defects and those induced during operation – to these assaults that is central to their resistance. The fact that structural alloys exhibit strengths that are typically only 5% of theoretical limits and reactor vessel steels exposed to neutron irradiation become brittle over time – thereby limiting nuclear reactor operating efficiency and lifetime – is unarguably a consequence of limits in our understanding of defects and inability to better control their deleterious effects.
The CDP’s approach is based on three interrelated research thrust areas, Fundamental Physics of Defect Formation and Evolution during Irradiation; Fundamental Physics of Defect Interactions during Deformation; and Quantum Theory of Defects and Their Interactions, that will deploy first-of-their kind measurements of defect dynamics as well as large-scale and highly accurate first-principles-based (or ab initio) atomic-level simulations that will extend the boundaries of simulations of the structure and dynamics of extended defects.
In addition to other efforts, the center will enable the first measurements of defect dynamics in radiation cascades including the initial picoseconds that set the stage for later defect evolution. This experimental information is critical to understanding how structural materials react to extreme radiation environments and to test theoretical models. The center will also deploy novel techniques to quantify the local stresses around dislocations including individual dislocations and how their stress fields are affected by other defects. This information is essential to understanding how materials react to stress fields and how that behavior is affected by the local defect structure. These experimental programs will be supported by theory and modeling efforts that deploy novel algorithms and the most powerful computers available to push the boundaries of ab initio simulation. Altogether the center will greatly extend the experimental foundations of defect physics and will provide new computational tools to model and understand defect dynamics.
Just as transformative science requires new methods and high goals, we also seek to transform the next generation of scientists into top, cross-disciplinary researchers. To achieve this, promising undergraduate students will be sought to become actively engaged in research - where possible, this will be leveraged using other Department of Energy (DOE) programs for undergraduate opportunities. We are also teaming up with three other EFRCs that have similar focuses: Los Alamo National Laboratory’s Extreme Environment-Tolerant Materials via Atomic Scale Design of Interfaces, Idaho National Laboratory’s Center for Materials Science of Nuclear Fuel, and the University of Notre Dame’s Materials Science of Actinides. The four EFRCs will jointly host a Summer Institute, rotating its location between the four EFRC locations. Institute sessions will be one to two weeks every summer, and will be attended by the postdocs and students from all four EFRCs.
To strengthen collaborations within the Center, and to help train and educate the next generation of scientists, postdocs and students working at collaborating institutions will be encouraged to spend time at ORNL, working directly with Center scientists, making use of facilities at ORNL, and providing new ideas and capabilities from other institutions. Similarly, postdocs and students at ORNL will spend time at other institutions as applicable; broadening their own experiences and bringing back important scientific knowledge and capabilities to ORNL.
In Summary: The CDP
- The Energy Frontier Center for Defect Physics in Structural Materials, or Center for Defect Physics
- Studying material defects
- Three thrusts:
1. Fundamental Physics of Defect Formation and Evolution during Irradiation
2. Fundamental Physics of Defect Interactions during Deformation
3. Quantum Theory of Defects and Their Interactions
- Annual “ Summer Institute”
- Website coming soon
In summary, it is the goal of the Center to usher in a new level of understanding of defects physics that is built on quantitative measurements of fundamental defect dynamics and the unit events that underpin the complex and collective behavior of deformation and fracture. It is motivated by the premise that an increased understanding of this type of fundamental defect physics can lead to more active control of defects and the charting of new pathways to the development of improved materials – materials with potentially undreamed of strength, toughness, radiation damage tolerance, and self-recovery.
The FIRST Center
In the Fluid Interface Reactions, Structures, and Transport, or FIRST, Center, a highly integrated approach using state-of-the-art computational and characterization methods will be used to develop new conceptual and quantitative models describing the structural, reactive and transport properties of the Fluid-Solid Interface, or FSI.
The interaction of fluids with solid substrates controls many chemical processes encountered in nature and industry. Despite this, the atomic/nanoscale reactivity, structures and transport properties of the fluid-solid interface, or FSI, are poorly understood for the vast majority of fluid and substrate combinations, particularly at environmental extremes (for example, high temperature or pressure, or high surface charge density). This lack of fundamental molecular-level understanding of interfacial phenomena has often lead to Edisonian approaches to the resolution of technological challenges related to advanced energy technologies. This contributes to our inability to tailor interfacial systems efficiently, or to predict performance. To address these challenges, a paradigm shift is needed in our understanding of the FSI, away from continuum solvent descriptions and hypothetical interfacial structures, toward a quantitative, fully dynamic, and chemically realistic description of the interactions of electrons, atoms and molecules that give rise to macroscopic fluid/solid interfacial properties.
This Center will bring together a multidisciplinary team of scientists, postdoctoral associates and students to redefine the FSI and enable predictive understanding and control of interfacial processes. The overarching goal of the FIRST Energy Frontier Research Center will be to address the fundamental gaps in our current understanding of interfacial systems and answer these questions of high importance to future energy technologies:
- How does the interfacial region differ in structure, dynamics and reactivity from the bulk properties of the fluid and solid phases?
- How do these altered properties couple with complex interfacial textures to influence chemical reactions, ionic and molecular transport and charge transfer within and across the interface?
- How can we control and manipulate interfacial phenomena by informed selection of fluid- and solid-phase components, interfacial geometries, field gradients, temperature, pressure and other environmental parameters?
These questions permeate the fundamental science needed to solve our nation’s long-term energy production, storage, and utilization needs.
This effort will be pursued in three parallel thrusts that address increasing levels of FSI complexity, ranging from the alteration of the bulk fluid and solid properties due simply to their juxtaposition at a planar interface (Thrust 1), to the effects of surface roughness, porosity and functionalization on fluid transport properties (Thrust 2), to surface reactions that are mediated by the interfacial fluid (Thrust 3).
To the right is the commonly-invoked, but century-old, Gouy-Chapman-Stern-Helmholtz concept of the electrical double layer (EDL) at the interface between a negatively-charged metal oxide surface and an aqueous electrolyte solution. We intend to replace such static, hypothetical, continuum models with what we will refer to as “FSI models” that capture the atomic-molecular-nanoscale structural, reactive and transport properties of real interfaces, over the relevant time (femtosecond-millisecond) and length (sub-angstrom to sub-micron) scales of interfacial systems. This will provide an unprecedented level of understanding, predictability and control of interfacial transport and reactivity, and provide guidance for the design of new materials with extraordinary properties to address our future energy needs.
An important part of addressing those needs is preparing a new generation of scientists to meet them. The FIRST Center’s Education and Outreach Program is focused on this goal. Its leaders will work with our academic partners to bring FIRST science into the classroom, and will develop programs to inspire and train the next generation of scientists with interdisciplinary skills needed to meet the energy challenges of the future.
Towards this end, the Center will provide support for 15 Postdoctoral Fellowships, 4 graduate students, and 4 undergraduates. We will also provide travel funds for FIRST team members to visit other institutions and gain critically needed expertise and/or conduct experimental studies at major user facilities.
In Summary: The FIRST Center
- The Fluid Interface Reactions, Structures, and Transport Center
- Studying the atomic/nanoscale reactivity, structures, and transport properties of the fluid-solid interface
- Three Thrusts:
- Fluid-Solid Interface Model Development
- Electrode/Electrolyte Interactions
- Fluid-Mediated Surface Reactions
- Strong training for next generation’s scientists:
- Work in classrooms
- Supporting postdoctoral fellows and students of a variety of levels both at the FIRST Center and at partner institutions
- More at the FIRST Center Homepage
We are excited about these new centers, and eagerly await the chance to address current and future energy challenges!