Abstract:

Mastery over solid-state ion transport is paramount for broad diversity of applications and technologies, including batteries, fuel cells, neuromorphic computing, and beyond. Both static and dynamic disorder play a crucial role in dictating ion diffusion processes in the solid state. Our work seeks to understand and harness disorder across time and length scales to impact ion transport processes. This seminar will highlight two studies that emphasize static and dynamic disorder – and the interplay between them – in two families of solid-state ion conductors. The first vignette will highlight our work in understanding atomic site disorder in lithium metal halide solid-state ion conductors. We have recently discovered several new earth-abundant spinel ion conductors, including Li-Mg-Zr-Cl and Li-Zn-Zr-Cl. Incorporating multiple cations in the spinel structure triggers a significant rearrangement of the cation local structure that creates a larger number of low-energy pathways for lithium-ion transport. The second vignette will focus on argyrodite solid-state ion conductors. The argyrodites Li6PS5X (X = Cl–, Br–, I–, CN–) are amenable to a large degree of both static and dynamic disorder that conspire to influence mobile ion dynamics. Through local structure probes, we have identified signatures of PS4 rotational disorder. The amplitude of these (presumably dynamic) rotations is correlated with the presence of site disorder and with higher lithium-ion conductivity. We further couple the presence and extent of rotational disorder with the underlying contributions to lithium-ion transport. Taken together, this work illustrates the nuanced role of static and dynamic disorder in solid-state ion transport.

Speaker Bio:

Prof. Annalise Maughan is an Assistant Professor in the Department of Chemistry at Colorado School of Mines and holds a joint appointment with the National Renewable Energy Laboratory (NREL). She received her B.S. in Chemistry from Northern Arizona University and her Ph.D. in Chemistry from Colorado State University working with Prof. Jamie Neilson. She then joined the National Renewable Energy Laboratory (now the National Laboratory of the Rockies) as a Director’s Postdoctoral Fellow prior to joining the faculty at Colorado School of Mines in 2021. Her research program is focused on solid-state materials chemistry for renewable energy, with an emphasis on understanding the fundamental principles that connect chemistry, local and long-range structure, and dynamics to functional properties such as charge transport and light absorption/emission. She is the recipient of several awards, including the NREL Foundation’s Outstanding Woman in STEM Award, the NSF CAREER Award, the Department of Chemistry Outstanding Faculty Award, the W. M. Keck Award for Graduate Mentorship, and the 2025 Chemistry of Materials Lectureship and Best Paper Award.