Real time Imaging of surface catalytic reactions

This review focuses on various methods to image surface reactions in real time. Development of the photoelectron emission microscope (PEEM), which is capable of following local work function changes in real time, was of fundamental importance in work dedicated to understanding pattern formation during catalytic reactions. The focus of this review is on optical methods using polarized light capable of imaging adsorbates on top of the surface, which are typically less than one monolayer (ML) thick. These imaging methods include Ellipso Microscopy for Surface Imaging (EMSI) and Reflection Anisotropy Microscopy (RAM), and the commercially available infrared (IR) technique, which nowadays can follow reaction fronts due to the temperature change even at low pressures. Some new results will be presented where in addition to the optical imaging a focused laser was used to change pattern formation during the CO-oxidation on a Pt(110) surface in various ways.