ELECTRON MICROSCOPY OF SINGLE-WALLED CARBON NANOTUBES DURING GROWTH ON CoMo BIMETALLIC CATALYSTS
EMSL Project ID
14590
Abstract
Single-wall carbon nanotubes (SWNT) can be considered as one of the building blocks for nanoscale science and nanotechonology. Our group has focused on the disproportionation of CO on bimetallic CoMo catalysts, which exhibited a high selectivity toward the production of SWNT at relatively low temperatures. This good performance has been linked to the interaction between Co and Mo, in the form of a surface cobalt molybdate species, which under reaction conditions becomes Mo carbide and generates small clusters of metallic Co, in turn active for the growth of SWNT. We propose to investigate the growth mechanism of SWNTs over a CoMo bimetallic catalyst using a model system: CoMo supported on a lacey silicon monoxide grid. Our preliminary results show that the length of SWNTs increases with increase with reaction time. These observations are in agreement with Raman studies performed on the same materials. No carbon signal appears during the first few minutes, despite a strong modification in the spectrum. The typical bands characteristic of SWNTs, start appearing only after 3 minutes in contact with CO and become very strong after 10 minutes under reaction.Project Details
Project type
Exploratory Research
Start Date
2005-06-06
End Date
2006-04-13
Status
Closed
Released Data Link
Team
Principal Investigator