Defects on the Pt(100) surface and their influence on surface reactions—A scanning tunneling microscopy study

Abstract

Structural differences between a clean, reconstructed Pt(100) surface and one exhibiting chemical or structural irregularities have been identified by means of a scanning tunneling microscope. The (temperature-dependent) defect structure of a surface which had undergone a phase transition involving mass transport was characterized and compared to results obtained using other techniques. The catalytic activity of surface step sites was probed by the thermal decomposition of ethylene. The resulting surface roughening and buildup of carbon, which could be resolved in STM images, clearly showed that the decomposition proceeds from terrace edges.