Nanopatterning Single-Crystalline Metal Electrodes via Ion Erosion: New Structural Motifs for Model Electrocatalysis.

Model studies in electrocatalysis provide valuable insights into complex structure-property relationships and rely heavily on experimental techniques that enable the preparation of electrode surfaces with atomic-scale control over morphology. This work investigates the nanopatterning of single-crystalline metal electrodes through ion erosion. On Pt(111), ion erosion produces surfaces with distinct corrugation, characterized by the formation of erosion pits, an equal proportion of (110) and (100) steps, and a high density of kinks. The obtained structural motifs influence the electrochemical behavior of H/OH adsorption/desorption and surface electrooxidation in a unique manner, illustrating that ion-eroded metal surfaces represent a complex but atomically precise platform for exploring the synergistic action of various types of surface defects on the electrode properties. A general applicability of ion erosion is demonstrated by preparing and characterizing ion-eroded surfaces of Ru(0001) and Cu(111), showing that this method can control the density of surface defects in ways that are challenging to achieve through the traditional Clavilier method. Ion erosion enables the imprinting of a variety of surface configurations, ranging from atomically flat to stepped and disordered structures, on a single-crystal substrate, offering new avenues for designing electrodes with tailored reactivity.