Surface Dynamics in the Early Stages of Metal and Alloy Oxidation
Oxidation is one of the most fundamental processes affecting metals and alloys, with implications for corrosion, catalysis, energy conversion, and high-temperature applications. While we understand a great deal about how oxygen interacts with surfaces and how thick, stable oxides grow, the earliest stages of oxidation – how the very first oxide islands form and evolve – remain a mystery. These transient steps are critical, since they often determine the long-term properties and performance of materials. Using state-of-the-art in situ electron microscopy, we directly observe how oxides nucleate and grow on copper surfaces at the atomic scale. Surprisingly, the process looks very much like crystal growth in thin films, where diffusion and strain play key roles in shaping oxide morphology. By combining these experiments with atomistic simulations, we explain why specific oxide structures form more readily than others. We are now extending this approach to alloys, where the added complexity of multiple elements makes oxidation even richer and more technologically relevant. Together, these studies shed light on the fundamental surface dynamics that govern how metals and alloys interact with their environment.
Bio: Judith C. Yang, Ph.D. ’93, is group leader of the Electron Microscopy Facility at the Center for Functional Nanomaterials, Brookhaven National Laboratory, and is affiliated with the Department of Materials Science and Chemical Engineering at Stony Brook University. She is on leave from the University of Pittsburgh, where she spent more than two decades on the faculty and held the William Kepler Whiteford Professorship of Engineering.
A Cornell alumna (Ph.D., physics, 1993), Yang conducted postdoctoral research at the Max-Planck-Institute of Metallforschung in Stuttgart, Germany, and at the University of Illinois at Urbana-Champaign before joining the University of Pittsburgh faculty in 1999. She has received the NSF CAREER Award, the Chancellor’s Distinguished Research Award, and is a Fellow of both the American Physical Society and the Microscopy Society of America. From 2019-2022, she served as a program director at the National Science Foundation. Her research focuses on oxidation, catalysis, nanomaterials, gas-surface interactions, and in situ electron microscopy.