(538c) Interfacial Carbene Reactions on Hard and Soft Material Interfaces

We will discuss an interfacial carbene insertion on hard and soft material interfaces. Interfacial carbenylation in a new molecular layer deposition technique, capable of functionalizing diverse materials (inorganic, organic, polymeric including flat, curved, rough or nanostructured interfaces) with uniform and stable monolayers or thin films of functional organic molecules. Instead of using self-assembly and ordering to form stable monolayers, we utilize active carbene precursors to enable rapid liquid or vapor-phase formation of thermodynamically and kinetically stable surface bonds. Such chemisorption produces dense and uniform monolayers or multilayered thin films that do not require extensive intermolecular interactions for stability.

Recently, we demonstrated that a novel, vapor-phase carbenylation strategy can be used to form dense monolayers of functional organic molecules on passivated hard and soft interfaces. These monolayers are attached to the surfaces via non-hydrolytic Si-C and C-C bonds making them less prone to hydrolytic cleavage than typical SAMs on oxides and metals. However, due to their non-symmetrical structure, they do not have self-assembled phases and have slightly lower molecular surface coverage than the traditional aliphatic SAMs. Nonetheless, due to their exceptionally strong surface attachment, the stability of such monolayers is primarily determined by the reactivity of the underlying substrates, and not by the attachment chemistry. We demonstrated, that the carbenylation method can serve as a complementary technique to the traditional SAM methodology in applying functional molecular coatings on the substrates, which are typically incompatible with the traditional molecular self-assembly.