Iridium oxide (IrO2) is the state-of-the-art electrocatalyst for water oxidation in electrolyzers yet it suffers from instability under operating conditions. Here we combine first-principles modeling with in situ liquid-phase transmission electron microscopy and device-scale characterization to resolve the atomic-scale morphology and dissolution dynamics of IrO2 nanocrystals. Our computational Wulff constructions uniquely incorporate high-index facets providing new insights into thermodynamic facet-dependent stability under operating conditions. Atomically resolved studies reveal multiple distinct collective dissolution pathways including high-index facet formation monolayer reconstruction step-edge formation and monolayer delamination on {110} surfaces. Device-scale studies confirm that electrochemical operation results in high-index facet formation. Ab initio molecular dynamics simulations further show that initial dissolution kinetics are facet-dependent. These findings highlight how combining in situ imaging with first-principles modeling reveals atomic-scale dynamics that influence material performance.
This dataset includes a collection of the videos analyzed for the publication. All video files were created on 2026-02-01. These videos are stored as collections of .tif files at a framerate of 1 fps and at a resolution of 1024x1024. This is a subset of the data collected as the full-fidelity dataset is between 1 and 10 fps and 4096x4096. However due to institutional restrictions on the maximum size of data that is storable these reductions were necessary. The full-fidelity dataset will be provided upon request to the corresponding author.
This dataset includes a collection of the videos analyzed for the publication. All video files were created on 2026-02-01. These videos are stored as collections of .tif files at a framerate of 1 fps and at a resolution of 1024x1024. This is a subset of the data collected as the full-fidelity dataset is between 1 and 10 fps and 4096x4096. However due to institutional restrictions on the maximum size of data that is storable these reductions were necessary. The full-fidelity dataset will be provided upon request to the corresponding author.