Model catalyst surfaces investigated by scanning tunneling microscopy

Scanning tunneling microscopy (STM) has become established as a versatile technique for direct, real-space investigations and characterization of matter at the atomic level. Recent progress in STM studies of model systems relevant to heterogeneous catalysis has shown that it is possible to resolve fundamental issues related to catalytic processes by atomic-scale imaging of catalytically active surfaces and nanostructures. In this chapter, we briefly introduce the basics of the STM technique and the framework needed to understand the electronic and geometrical information contained in STM images. We highlight recent developments of the STM technique that will help further the elucidation of understanding of catalysts in the working state, and illustrate how the level of insight gained from characterizing model systems has advanced to a stage where the insight and ideas may lead to the design of new and improved high-surface-area catalysts.