Electron spectroscopy and electrochemical scanning tunneling microscopy of the solid-liquid interface: Iodine-catalyzed dissolution of Pd(110)

This article showcases the unique capabilities afforded by the combination of electron spectroscopy, scanning tunneling microscopy, and electrochemistry in the study of complex processes at the electrode-electrolyte interface. The interfacial reaction investigated was the anodic dissolution of a Pd(110) single-crystal surface catalyzed by a single chemisorbed layer of zerovalent iodine atoms. Previous work had shown that dissolution of the two other low-index planes, Pd(100) and Pd(lll), altered neither the adlattice structures nor the interfacial coverages. In comparison, while the anodic dissolution of the Pd(110)-I surface did not lead to changes in the iodine coverage, it resulted in a disordered surface. The in situ STM work provided valuable insight as to why the initial and post-dissolution structures were not identical.