Photoelectrochemical <i>i</i> <i>n</i> <i>s</i> <i>i</i> <i>t</i> <i>u</i> observation of <i>n</i>-MoS2 in aqueous solutions using a scanning tunneling microscope

Abstract

A scanning tunneling microscope under potentiostatic control in visible light illumination was used in aqueous solutions to investigate an in situ dynamical light-induced morphological transformation of n-MoS2, a representative layer-type semiconductor electrode. In a KCl solution, light-induced corrosion originated from ‘‘layer-island’’ structures, island edges, and depressions, all of which served as active reaction sites. The electrode surface was then morphologically transformed by photoelectrochemical processes into a stable van der Waals’ surface. Additionally, the effect of I− ions on the suppression of photocorrosion of n-MoS2 was investigated.