We also rely on a variety of instruments available on campus to perform some of our work.The Samuel Roberts Noble Electron Microscopy Laboratory,located in the Biology/Microbiology building hosts a high-resolution SEM (JEOL 880) and a TEM (JEOL 2000FX) electron microscopes.
In addition, we use the EXAFS facilities at the National Synchrotron Light Source (NSLS) located in Brookhaven National Laboratory (NY). EXAFS experiments have allowed us to determine the crystal structure and details of chemical and physical phase transformations in our catalysts at different stages of the SWNT production process.
NSLS User Administration Office
The role of water in carbon feed on the surface-guided growth of horizontally aligned single-walled carbon
nanotubes (HA-SWCNTs) was investigated. It is shown that the amount of water can be optimized to favor HA-SWCNT growth, which is proposed to be due to selective etching of carbon deposits at carbon–metal interface. Without water, nanotube–nanotube interaction and carbon accumulation at the interface are disproportionately large compared to the rate of nanotube growth, leading to catalyst deactivation. With excess water, suppression of nanotube growth occurs, resulting in reduced carbon yield on the surface.
Intermediate carbon/water feed ratios achieve cleaner growth with high efficiency.