IMAGING OF THE INSITU DEPOSITION OF LEAD ON HIGHLY ORIENTED PYROLYTIC-GRAPHITE BY SCANNING TUNNELING AND ATOMIC FORCE MICROSCOPIES

The electrodeposition and stripping of lead has been studied by in situ and ex situ scanning-tunneling microscopy (STM) and in situ atomic force microscopy (AFM). The lead was electrodeposited on highly oriented pyrolytic graphite (HOPG). The HOPG was initially treated to produce monolayer deep pits which served as markers and supplied a high density of edge sites. Pb deposits preferentially formed at step and pit edges and resembled crystallite growth on a microelectrode disk. We discuss effects of tip potential on deposition during in situ STM and compare these results with AFM studies. After stripping, scanning microscopy and x-ray photoelectron spectroscopy indicated that residual Pb species remained on the surface.