Photophysical Studies of Nanocarbons

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

Technical: This project addresses three related research areas: double wall carbon nanotubes, resonance windows in single wall carbon nanotubes, and graphene studies. A systematic resonance Raman study of individual double wall nanotubes is planned along several research directions--complementary studies for the four DWNT configurations to investigate charge transfer behavior and strain effects with an effort to distinguish between the role of each of the mechanisms present in DWNTs. A study of the wall to wall distances associated with the above phenomena will also be investigated. Resonance windows of features in the Raman spectra of SWNTs, paying attention to effects of the diameter and chiral angle dependence, of each spectral feature, and to the effects that have been revealed for (2n+m) families of M-SWNTs and S-SWNTs. The project also includes collaborative research to improve the synthesis process for CVD large area growth of monolayer, bi-layer and few layer graphene samples. The main tool used to characterize the various graphenes will be the D-band, G-band and G0-band, regarding layer number and structural order, with special emphasis given to interlayer stacking. The behavior of all features in the Raman spectra for CVD grown graphene will be compared with samples produced by the mechanical exfoliation of highly oriented pyrolytic graphite (HOPG). Systematic Raman studies of CVD graphene will be carried out for samples grown by Jing Kong's group at MIT and annealed at a variety of temperatures in the range 1500-2800±C by collaborators Professors M. Endo and Y. A. Kim at Shinshu University in Nagano, Japan. Raman studies of the edges of graphene ribbons will also be carried out in an effort to clearly distinguish the differences between armchair and zigzag edges. Non-technical: The project addresses basic research issues in a topical area of materials science and condensed matter physics with technological relevance, and is expected to provide unique opportunities for graduate and undergraduate training in an interdisciplinary field. This research project is also expected to have broader impacts through the training of women and men leaders in this research field, through the wide dissemination of the findings of this research through invited talks and publications and through the preparation of tutorial review articles to relate the findings of this work together with other state-of-the-art work in this research field. The PI will continue to disseminate advances in nanoscience and nanotechnology to the public through invited talks to general audiences, industrial laboratories and professional societies, as she has done in the past. Her service in holding mentoring sessions for students and postdocs at numerous universities is expected to continue, as is her service to professional societies. This project is co-supported by the DMR Electronic Materials and Condensed Matter Physics Programs.