Dealloying Under Conditions of Significant Solid-State Mass Transport

This research program examines the kinetics of dealloying and morphology evolution in alloy systems for which the solid-state mass transport processes of lattice and grain boundary diffusion are significant at ambient temperature. In order to examine these issues we use a combined experimental and computational approach. The alloy systems under study are Li-Sn, Li-Pb and Li-Cd. These host metals and similar ones are currently being considered as anode reservoirs in future lithium-ion batteries and have been chosen for study since they represent variations in the host crystal structures; tetragonal, facecentered cubic and hexagonal close-packed respectively and have a rich history with abundant thermodynamic and kinetic data available. Electrochemical methods are used to produce the alloys, measure dealloying rates and determine associated solid-state mass transport rates. Dealloying morphologies are examined using scanning electron microscopy. Kinetic Monte Carlo simulations are used to model dealloying rates as a function of the electrochemical potential and morphology evolution.