Nguyen D.V., Nguyen K.C., Nguyen D.V., Nguyen K.C., Nguyen D.V., Nguyen K.C., Anh T.N.M., Thy N.N., Phat T.H., Hieu T.L.
SAIGON HI TECH PARK, VN
Keywords: carbon nano tube, solid phase synthetic process, tube control agent
The most recent carbon nano tube (CNT) products has been made by catalytic growth process in a CVD reactor system . The optimized process utilizes the gas phase carbon sources which is fed into reaction chamber as an admix of several gas vapors including metal catalyst, hydrogen carrier , N2 providing unoxidizing environment, and water vapor ,etc…Even though, the gas phase always exhibits very fast reaction rate and yields non uniform tubes . Reducing the reaction gas flow rate shows improvement of the uniformity but also reduce production throughput . These are remaining issues for the catalytic growth process with gas phase reaction . Recent years, we developed a new solid phase process of CNT, which shows some advantages over the conventional catalytic growth processes in term of uniformity with reasonable production throughput and the capability of providing well controlled tube shape in various format . The optimized solid precursor for the solid phase process is composed of solid state carbon source , catalyst and additives forming tube (tube control agent ;TCA) . In this process, it must require a reasonably good compatibility between three above mentioned components due to their chemistry and physical process of mixing them prior to the combustion . Particularly, TCA is selected from specific chemicals having –CN functionality effectively linking carbon sources with catalyst . Among three components of the solid precursor, the catalyst content seems to affect tube diameter while the chemistry of carbon source seems to affect tube length . It is also interesting to discover that the sub gas additives can also increase significantly the tube diameter up to 600nm . These giant tube can be arranged into a uniform tube array useful for nano filtration of water, blood . Recently, we also found natural resources from tropical area in Viet Nam can successfully form tube products such as rubber tree latex, coffee bean, cedar wood , jetropha seed etc, Each ethnic feature also requires different combination of TCA and catalyst, revealing the capability of discovering new tube shapes such as twisting tube or straight tube , short tube (a few hundred nm long) , Y shape tube for various kinds of applications in nano composite , AFM tip, diagnostic etc, …
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2009: Fabrication, Particles, Characterization, MEMS, Electronics and Photonics
Published: May 3, 2009
Pages: 5 - 7
Industry sector: Advanced Materials & Manufacturing
Topics: Advanced Manufacturing, Nanoelectronics
ISBN: 978-1-4398-1782-7