CAREER: Probing and Exploiting Short-range Order in Crystalline Materials for Fast Ion Transport

University Of Utah, Salt Lake City UT

Investigators

Abstract

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Non-Technical Summary: Fast ion conductors are major players in energy storage, a strategically critical area for the holy grail of vehicle electrification and the best solution to the intermittent and random nature of many renewable energy sources, such as solar and wind. Past research has heavily focused on ion conductors with perfect prototype structures. As a result, further materials discovery was limited to incremental improvement and a narrow range of chemistry. In this project, with support from the Solid State and Materials Chemistry program in the Division of Materials Research, the principal investigator investigates structurally-disordered ion conductors with compositional flexibility that can potentially alleviate the industry’s reliance on any single critical metal source which has broad societal impact. The project also integrates education and research to increase enrollment and retention of STEM students, creating America’s future STEM workforce. In pursuit of these goals, the PI creates demonstration kits for college teaching and K-12 outreach, a crystal growth course with hands-on research-based activities, and a novel augmented reality experience for interactive crystallography pedagogy. Technical Summary: The facile transport of ions in crystalline materials enables key functionality in various devices, such as batteries, membranes, and fuel cells. The structural characterization of these materials, however, presents an outstanding challenge. Their crystal structures often exhibit short-range order, whereas traditional diffraction-based techniques are only sensitive to long-range periodic features. As a result, past research either had to ignore it for lack of instrument sensitivity or avoided it completely for fear of complexity and unpredictability. This CAREER project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, overcomes these difficulties by performing state-of-the-art synchrotron and neutron scattering on judiciously selected ion conductors, to precisely characterize these structural subtleties in both the mobile ion and the framework sublattices. The project also systematically modifies the chemistry and synthesis variables and correlates these parameters with structural observations and property measurements to reveal previously overlooked structure-property relationships. These insights enable the design of disruptively new materials with fast ion transport and excellent economic sustainability. The PI also engages in a series of education and outreach activities by taking an approach centering on research-based, hands-on activities, to reinforce cognitive knowledge and retention and stimulate students’ interest in higher STEM education and careers. Specific efforts include: (1) outreach to middle and high schools with STEM activity kits; (2) expansion of the hands-on lab sessions in a crystal growth course; and (3) creation of an augmented reality app for interactive crystallography pedagogy. 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.