Unraveling giant Cu(110) surface restructuring induced by a non-planar phthalocyanine

Abstract

The surface stability of coinage metals is paramount when they are used as electrode materials for functional electronic devices incorporating organic semiconductors. In this work, it is shown that the adsorption of non-planar vanadyl phthalocyanine molecules on Cu(110) drastically restructured the metal surface at room temperature, which was further enhanced upon moderate annealing. Scanning tunneling microscopy imaging demonstrated that the surface was restructured at step edges into sawtooth features that gradually replaced the (110) terraces. The edges of the modified steps were preferentially composed of chiral (1×6) kink sites decorated with vanadyl phthalocyanine molecules adsorbed in a tilted configuration with the oxygen atom pointing downwards. These results can have a strong impact on the optimization of the performance of organic devices integrated with phthalocyanine molecules.