This grant addresses two issues critical to manufacturing at the nano- and meso-scales: (1) Can self-assembled DNA scaffolds be used to self-assemble complex photonic and electronic structures? (2) Can parts of the scaffold itself be used as active components of such assemblies? Self-assembled DNA nanostructures based on Watson-Crick base-pairing (and the assembly of three-way junctions) are made simply by mixing together component DNA sequences and annealing the mix. Large (mm-scale) arrays of nanometer-scale motifs have been reported. Such arrays can be made addressable, and can incorporate chemical function and optical elements, opening up new possibilities for building electronic, photonic and chemical devices. Designed appropriately, the cost of arrays that cover surfaces can be quite small, perhaps a few dollars per square meter of surface covered. This grant focuses on renewable energy. The scaffolds could position quantum dots, photonic antennas, catalysts for light-driven hydrogen generation or conducting polymers for rationally-designed photovoltaics. One type of array will incorporate antenna structures that concentrate light on molecules that separate charge. The goal is to absorb all incident sunlight in just a monolayer of dye molecules, which would greatly simplify the design of molecular photovolataic devices.
If successful, this approach opens up the possibility of incorporating a high degree of optical and electronic complexity into a supramolecular system that is entirely self-assembled. Nano-engineered materials that mimic nature's energy production (but that are also much more robust) could contribute a new approach to the generation of renewable energy. A partnership with Motorola offers possibilities for economic development of the technology.
