ELECTRON TOMOGRAPHY OF A CARBON NANOSTRUCTURE COMPOSITE
Thomas F. Lam,1 Jonathan P. Winterstein,2 Andrew A. Herzing,3 Pierre Kabro,4 Renu Sharma,1 and J. Alexander Liddle1
1Center for Nanoscale Science and Technology, National Institute of Standards and Technology, 100 Bureau Dr., Gaithersburg, MD 20899
2FEI Company, 5350 NE Dawson Creek Dr., Hillsboro, OR, 97124
3Materials Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Dr., Gaithersburg, MD 20899
4Applied NanoStructured Solutions, LLC, 2323 Eastern Blvd., Baltimore, MD, 21220
The incorporation of carbon nanostructures (CNS) into a polymer matrix to form a composite enables the development of materials that can be engineered with specific combinations of desirable properties – electrical, thermal, optical and mechanical, etc. However, this multifunctionality is dependent on the detailed arrangement – dispersion, clustering, networking, etc. – of the CNS within these composites. To image these CNS morphologies at high spatial resolution, we use transmission electron microscopy (TEM).
High-quality, electron-transparent samples are prepared from such heterogeneous materials using a dual-beam focused ion beam (DB-FIB). Imaging nanoscale carbon reinforcements embedded within an amorphous carbon matrix (i.e. epoxy resin) with sufficient contrast is challenging. In this research, energy-filtered TEM (EFTEM) is used to understand and optimize contrast differences between the two carbonaceous phases. The CNS morphology and distribution in three dimensions is analyzed quantitatively using EFTEM tomography. EFTEM tomography results from a complex industrial nanocomposite sample consisting of CNS grown on carbon fiber and embedded in epoxy resin will be presented.