Bifunctional patterning of mixed monolayer surfaces using scanning probe lithography for multiplexed directed assembly

The patterning of a surface with more than one type of functionality in spatially resolved fashion is described. A scanning probe was used to create patterns composed of two orthogonal types of functionality within a dense, electrochemically active mixed monolayer via a simple modulation of the applied surface bias. One reductive pathway produces surface-bound amine moieties while the other creates an oxidized surface. The two newly created surface functionalities can each be used independently to locally deposit complementary materials such as electron- or hole-transporting molecules via self-assembly.