Carbon-based nanomaterials have attracted significant attention due to their potential to enable and/or improve applications such as transistors, transparent conductors, solar cells, batteries, and biosensors [1,2]. This talk will delineate chemical strategies for enhancing the electronic and optical properties of these promising nanomaterials. For example, we have recently developed a scalable technique for sorting single-walled carbon nanotubes (SWNTs) by their physical and electronic structure using density gradient ultracentrifugation (DGU) [3,4]. The resulting monodisperse SWNTs possess unprecedented uniformity in their electronic and optical properties, which enables the fabrication of high performance thin film field-effect transistors [5,6], infrared optoelectronic devices , and transparent conductors . The DGU technique also enables multi-walled carbon nanotubes to be sorted by the number of walls , and solution phase graphene to be sorted by thickness [9,10], thus expanding the suite of monodisperse carbon-based nanomaterials. By recently extending our DGU efforts to carbon nanotubes and graphene dispersed in biocompatible polymers (e.g., DNA, poloxamers, etc.), new opportunities have emerged for monodisperse carbon-based nanoelectronic materials in biomedical applications. As a final example, this talk will discuss the preparation and characterization of highly ordered self-assembled monolayers on graphene. In particular, self-assembled monolayers of perylene-based molecules are noncovalently formed on graphene via gas-phase deposition in ultra-high vacuum at room temperature , while covalent modification is achieved via solution-phase diazaonium chemistry . Ultimately, organic functionalization allows the chemical properties of graphene to be tailored for subsequent materials deposition in addition to presenting opportunities for graphene-based molecular electronic and sensing devices.
Mark C. Hersam is currently a Professor of Materials Science and Engineering and a Professor of Chemistry at Northwestern University. He earned a B.S. in Electrical Engineering from the University of Illinois at Urbana-Champaign (UIUC) in 1996, M.Phil. in Physics from the University of Cambridge in 1997, and a Ph.D. in Electrical Engineering from UIUC in 2000. In 1999, he was a researcher at the IBM T. J. Watson Research Laboratory under the support of an IBM Distinguished Fellowship. His research interests include single molecule chemistry, nanofabrication, scanning probe microscopy, semiconductor surfaces, and carbon nanomaterials. In recognition of his early career accomplishments, Hersam was directly promoted from assistant professor to full professor with tenure in 2006. In 2007, he co-founded NanoIntegris, which is a start-up company focused on supplying high performance carbon nanomaterials.
Chemistry Departmental Colloquium
- M. C. Hersam, Nature Nanotechnology, 3, 387 (2008).
- J. Liu and M. C. Hersam, MRS Bulletin, 35, 315 (2010).
- M. S. Arnold, et al., Nature Nanotechnology, 1, 60 (2006).
- A. A. Green, et al., Nano Research, 2, 69 (2009).
- M. Engel, et al., ACS Nano, 2, 2445 (2008).
- L. Nougaret, et al., Applied Physics Letters, 94, 243505 (2009).
- A. A. Green and M. C. Hersam, Nano Letters, 8, 1417 (2008).
- A. A. Green and M. C. Hersam, Nature Nanotechnology, 4, 64 (2009).
- A. A. Green and M. C. Hersam, Nano Letters, 9, 4031 (2009).
- A. A. Green and M. C. Hersam, Journal of Physical Chemistry Letters, 1, 544 (2010).
- Q. H. Wang and M. C. Hersam, Nature Chemistry, 1, 206 (2009).
- E. Bekyarova, et al., Journal of the American Chemical Society, 131, 1336 (2009).
Cite this work
Researchers should cite this work as follows:
WTHR 104, Purdue University, West Lafayette, IN