Abstract
Faceting occurs when an initially planar surface undergoes a morphological rearrangement exposing nanoscale new crystal faces (facets). Both morphology (shape) and structure of the faceted surface differ substantially from those of the initial planar surface. In this review, we will give an overview of adsorbate-induced faceting of metal single-crystal surfaces, identification of facets, and utilization of faceted metal single-crystal surfaces as nanoscale model catalysts to bridge the material gap between planar metal single-crystal surfaces and supported metallic nanoparticles, and as nanotemplates to synthesize metallic nanoparticles (nanosclusters) and nanostructured metallic monolayer electrocatalysts. The well-defined facets allow for detailed experimental and theoretical characterization that provides insights into structure–reactivity/selectivity relationships, which is crucial for improving reactivity and selectivity by controlling the nanoscale morphology and size distribution of heterogeneous catalysts.