Title: Materials Discovery at Extreme Pressures
Abstract: The ability to study matter under extreme pressures and temperatures has opened up a vast new playground for solid-state chemists to explore. No longer are elemental systems partitioned into those that form compounds and those that do not. Instead, the question has become: under what conditions do these systems form stable phases, and can these new phases be recovered? For materials scientists, extreme pressure represents a treasure trove of exotic compounds awaiting discovery—new materials that could propel next-generation or even as-yet unimagined technologies. In this talk, I will describe some new methods being developed in our lab that will empower solid-state chemists with the tools they need to target and recover new high-pressure phases. In particular, I will share some of our recent results on the discovery of novel transition metal carbides, demonstrating how our methods have allowed us to carry out the highly selective synthesis of high-pressure phases. I will also present results using nanosecond timescale X-ray diffraction to study materials in the shock-compressed state. These cutting-edge experiments allow us to study crystal structures under highly non-equilibrium conditions and might one day open up a completely novel approach to synthesis.
Bio: James Walsh is an Assistant Professor at the University of Massachusetts Amherst, where he began his independent career in 2019. James received his PhD in 2014 from the University of Manchester in the United Kingdom, working with Professor David Collison on the study of molecular nanomagnets. Following his PhD, James carried out research as a postdoctoral fellow at Northwestern working with Danna Freedman, where he studied high pressure as a tool for the synthesis of novel bismuth binary phases. His group’s research is supported by an NSF CAREER award (2022) and the ACS Petroleum Research Fund (2023).
