Dynamic Observation of Carbon Nanotube Growth on Isolated Catalyst Nanoparticles

Project: Research project

Project Details

Description

Intellectual merit This is a request for REU supplement for our currently funded project. We propose to determine the synthesis conditions for making carbon nanotubes having specific targeted structures and properties. We will accomplish this by a two-step process in a high-resolution (< 0.2 nm) controlled environment (scanning) transmission electron microscope (ESTEM). We have successfully grown carbon nanotubes from Fe catalysts deposited on SiO2 supports from Fe2(CO)9 by the electron beam induced deposition (EBID) method, followed by an annealing step. We have generated a vast amount of video images that needs to be processed (at the rate of 15 frames per second, one minute video contains 900 images). REU student will be involved in writing programs for fast analysis of the images extracted from videos. We propose to measure growth rates as well as obtain information about the structural, morphological changes using these analytical tools. We are now exploring the effect of catalyst particle size and reaction temperature and pressure on nanotube structure. Supporting the experimental results, we will model the growth mechanisms using ab initio methods, with detailed attention paid to the catalyst/nanotube interactions. REU student will also model the topologies of individual nanotubes and their defect structures. The techniques we develop can be used to form other model catalysts for dynamic imaging in order to understand their behavior in reactive environments. These results will be beneficial to a wider scientific research community, as EBID is an emerging tool for forming nanostructures, as well as the nanocontacts, in the electronics and semiconductor industry. Similarly, advancing our knowledge of the catalysis process of hydrocarbons, at the atomic level, will have direct implications for petroleum research. Broader Impact The ability to control the fabrication of nanotubes would be an important step towards the broader goal of using them to building circuits or sensor boards. The methods developed can be used for designing other nanoscale devices. For example, electron beam induced depositions can be used to fabricate arrays of quantum dots. Combinatorial catalysis characterization techniques developed here will also be useful for studying catalysis at the atomic level at typical reaction temperatures, with possible implications for the design of other catalysts. The videos showing growth mechanisms, combined with models, form invaluable visual aids for undergraduate nanotechnology education (video is available on the NEU website) as well as for our K-12 outreach program. The PI (R.S.) has been a role model as a successful scientist for the undergraduate program at ASU. REU student will get training for data handling and data analysis.=0 c
StatusFinished
Effective start/end date9/1/068/31/10

Funding

  • National Science Foundation (NSF): $334,201.00

Fingerprint

Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.