This Materials Research Science and Engineering Center (MRSEC) at the University of Minnesota features two Interdisciplinary Research Groups (IRGs). The first team aims to access novel electronic and magnetic properties by direct application of strong local electric fields to promising new materials. This Quantum Leap aligned research will realize ready control over an extraordinary range of electronic phases and functions, thereby enabling new approaches to low-power magnetic data storage and processing, neuron-like computation, and nanophotonic devices such as solar cells. The second team is developing novel and systematic approaches to assembling polymeric materials into bicontinuous network structures with superior property combinations. These will advance multiple applications, including membranes for removal of viruses and bacteria, selective ion transport media for new battery designs, therapeutic delivery vehicles, and materials to manipulate light more efficiently in photovoltaic devices. The investigators provide extensive research experiences for promising undergraduates from a national network of four-year colleges, minority serving institutions, and especially tribal colleges. Summer camps for high school students, drawn from the Twin Cities and from Native American communities across the upper Midwest, involve senior investigators, students, and postdoctoral fellows in hands-on laboratory activities. Entertaining demonstration shows to illustrate fundamental scientific principles engage over 50,000 K-12 students each year. Close interaction with industry involves knowledge transfer in a pre-competitive collaboration with over 25 companies. Shared experimental facilities provide access to state-of-the-art materials characterization instrumentation to a national base of over 500 users.
IRG-1 aims to transform the understanding of mechanisms, capabilities, and applications of electrolyte-based gating, thereby realizing electrical control over an extraordinary range of electronic phases and function. Both electrostatic and electrochemical control are central to elucidating the biggest challenges facing ionic gating, and thus the development of ionic devices. These include understanding: when and why electrostatics vs. electrochemistry dominate; limits on speed, reversibility, and property modulation; interfacial structure, chemistry, and ion-carrier interactions; and universality of the approach. Three target materials classes are envisioned to tackle these issues – metal oxides, metal chalcogenides, and molecular conductors – chosen for alignment with key open issues and extraordinary functionality. The overarching goal of IRG-2 is to identify and translate design principles that direct small molecule self-assembly to oligomeric and polymeric shape-filling amphiphiles to form robust and functional mesoscopic network materials. Self-assembly strategies enable bottom-up design of nanostructured materials with tailored functionalities, accessing morphologies and properties exceeding those of their constituent building blocks. The interpenetrating microdomains of three-dimensional networks enable independent tuning of orthogonal properties in a single material. Crucially, the narrow composition windows over which networks typically form currently restricts their translation to applications. The team’s approach centers on identifying packing motifs that destabilize lamellar and cylindrical morphologies to broaden the composition phase windows of negative Gaussian curvature network phases. Control of phase selection and defect density by advanced processing in films and in bulk is also an important additional target.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
