Creating Stable Non-Critical Element Magnets
Distinguished University and Cabot Professor Laura Lewis, ChE/MIE, is leading a $2.1M Department of Energy grant, in collaboration with the University of Delaware, the Northeastern University Physics department, and the University of Warwick, UK, for “Designing Strong Stability in Non-Critical and Rare-Earth-Lean Magnetic Materials.” The grant is one of thirteen projects funded to support research in Critical Minerals & Materials by the Office of Basic Energy Sciences.
The existing portfolio of energy-critical materials will be expanded through interdisciplinary research that elucidates factors controlling stability in technologically important magnetic systems. These systems are essential to modern society, permitting the contactless interconversion of electrical, mechanical, and increasingly, thermal energies. Employing a combined theoretical-computational-experimental approach, strategies and design principles will be delineated to realize magnetic systems of low- or zero-rare-earth/platinum group element content. In particular, efforts will focus on understanding electronic and magnetic responses at the sub-nanometer scale that permit kinetic and/or thermodynamic access and control of magnetocrystalline anisotropy. These strategies will clarify essential lattice conditions, including atomic defects, chemical additives, and composition profiles along crystallite boundaries that are the most favorable for achieving magnetic stability.
Two complementary theoretical and computational approaches (Hamiltonian-type methods linking symmetry with physical phenomena and Density Functional Theory (DFT)-based Disordered Local Moment (DLM) techniques) will guide experimental protocols to achieve an understanding of magnetic stability. These efforts will address the fundamental science underpinning the intrinsic properties of magnetic materials which arise from a complex glue of electrons binding the nuclei of a material together, generating magnetism and determining atomic arrangements. Tightly coupled experimental efforts will examine the thermodynamic metastability, the lattice defect structure and the associated magnetic character of two families of ferromagnetic materials featuring atomic layers within the crystal lattice. Connections between theoretical, computational and experimental outcomes will be validated using advanced high-resolution probes of the crystal lattice condition, as impacted by thermal, chemical, strain and magnetic field energy contributions during synthesis and processing.
Outcomes of the project will allow access to competitive magnetic materials, comprised mainly of non-critical elements, that are thermally and kinetically stable at technologically relevant temperatures. Computational/theoretical information revealed during the project will guide the design of magnetic materials at the sub-nanometer scale as well as provide input for fine-tuning of synthesis and processing parameters. Further, it is anticipated that overarching design principles and processing protocols will be discovered in the course of this work that can be generalized to broader classes of materials.