Grant: Discovery Grants Program - Individual

This research program aims to advance both the fundamental and applied study of electroactive nanostructured graphene devices for chemical and biological sensing applications. Graphene-based nanostructures are emerging as one of the most powerful classes of new functional nanostructured materials. Graphene is a truly two-dimensional semi-metallic material in which electrons can move without scattering for several hundred nanometers even at room temperature, and more importantly, it's very sensitive to the local environment. The core of this research program will be based on the investigation of the electrical responses of chemical and biological sensors made from (i) receptor sites wired between graphene electrodes, and from (ii) physically adsorbed receptors on graphene flakes. The first part (i) of this project will be based on an efficient process by which graphene sheets can be cut to create molecular-scale (~ 2 nm) gaps. The end cap of the graphene will be functionalized with carboxylic acids that can be used to react with amine-terminated molecular wires (bridges) to reconnect the circuits. The molecular bridges will introduce a reactive site for attachment of biological macromolecules, nanoparticles or small molecules. In the second part (ii), we will take advantage of recent developments in nanotube and nanowire based sensors. Receptor molecules will be attached to graphene through the physisorption of aromatic or polyene anchors. Targets could bind to these sites through complementary chemistry or by guided self-assembly. The electrical response curves of the chemical or biological sensors will be measured using the requested apparatus. Nanofabrication methods will be used to construct these sensors, and the nanofabrication process will be studied using electrical transport, surface sensitive techniques and proximal probes. The proposed work will combine elements of organic chemistry, molecular biology, condensed-matter physics, nanomaterial science, and spectroscopy. The results of this research will help guide the development of new detection methods based on graphene nanostructured materials.