Technical: Carbon-based nanomaterials, including single-walled carbon nanotubes (SWNTs), double-walled carbon nanotubes (DWNTs), multi-walled carbon nanotubes (MWNTs), and graphene, have attracted significant interest in the scientific research community due to their superlative electronic, thermal, mechanical, and chemical properties. While impressive performance has been achieved on selected samples, large-scale technological development has been hindered by the structural inhomogeneity of as-synthesized carbon-based nanomaterials. In an effort to overcome this polydispersity problem, a technique called density gradient ultracentrifugation is employed to sort carbon-based nanomaterials by their physical and electronic structure. This project seeks to resolve the outstanding issues surrounding the preparation, characterization, and application of monodisperse carbon-based nanomaterials. Specific research objectives include: (1) Tuning co-surfactant ratio and loading to achieve monodisperse small diameter (< 1 nm) SWNTs due to their spectral advantages for near-infrared optoelectronic applications. (2) Demonstrating diameter and electronic type sorting of DWNTs in an effort to elucidate exciton energy transfer between concentric carbon nanotube shells. (3) Quantifying structure-density relationship for surfactant dispersed graphene as a function of surfactant type, co-surfactant ratio, density gradient, and pH. (4) Employing monodisperse carbon-based nanomaterials in electronic device and materials applications such as transistors, optoelectronics, transparent conductors, and sensors.
The project addresses basic research issues in a topical area of materials science with high technological relevance. It is anticipated that this research will lead to substantial intellectual property and commercialization opportunities. Furthermore, an important component of the project is an education and outreach plan that is well integrated with the aforementioned research objectives including: (1) Undergraduate curriculum development through a revision and updating of an interdisciplinary course entitled Nanomaterials. (2) Hands-on, inquiry and design-based curriculum development for pre-college students in collaboration with the Materials World Modules program. (3) Engaging students and the general public about science and science policy via the Northwestern University Science Policy Action Network.
