Manipulation of individual water molecules on CeO2(111)

Abstract

Water molecules adsorbed on the CeO2(111) surface are investigated by non-contact atomic force microscopy (NC-AFM) at several tip–sample temperatures ranging between 10 and 300 K. Depending on the strength of the tip–surface interaction, they appear as triangular protrusions extended over three surface oxygen atoms or as small pits at hollow sites. During NC-AFM imaging with the tip being close to the surface, occasionally the transfer of molecules between tip and surface or the tip-induced lateral displacement of water molecules to equivalent surface lattice sites is observed. We report how this situation can be exploited to produce controlled lateral manipulations. A protocol to manipulate the water molecules between pre-defined neighbouring equivalent adsorption sites of the regular lattice as well as across a surface oxygen vacancy is demonstrated.