Surface Patterning With Nanoprecision

By corralling self-assembled monolayers (SAMs) within the pores of a supramolecular network, chemists in Europe have developed a method for creating patterns over large surface areas with nanoscale precision (Nature 2008, 454, 618). Manfred Buck and coworkers at Scotland's University of St. Andrews invented the new fabrication platform, which they say could be used to build biosensors or molecular electronics. The researchers form their supramolecular networks on a gold surface by capitalizing on the hydrogen-bonding interaction (shown) between 1,3,5-triazine-2,4,6-triamine and perylene-3,4,9,10-tetracarboxylic diimide. The triamine's threefold symmetry gives rise to a honeycombed network full of hexagonal pores, which are subsequently filled with organothiol-based SAMs. "The combination of the network with SAMs offers considerable design flexibility, with the network providing an exact definition of structures in the substrate plane and the SAM permitting separate surface modification," the researchers note, adding that "the hybrid system can provide control on a length scale and at a precision not readily achievable otherwise."