[BNC-grads-list] Fwd: REMINDER: Nano Seminar: Placidus Amama INAC Postdoctoral Fellow BNC, Purdue, 1/25/07 @ 10:30 AM, BRK 1001 (Dendrimer-Templated Catalyst for Controlled Growth of Single-Wall Carbon Nanotubes by Plasma-Enhanced CVD)

[Annette M Cheever]

Begin forwarded message:

> From: Annette M Cheever <acheever at ecn.purdue.edu>
> Date: January 24, 2007 3:11:48 PM EST
> Subject: REMINDER: Nano Seminar: Placidus Amama INAC Postdoctoral  
> Fellow BNC, Purdue, 1/25/07 @ 10:30 AM, BRK 1001 (Dendrimer- 
> Templated Catalyst for Controlled Growth of Single-Wall Carbon  
> Nanotubes by Plasma-Enhanced CVD)
>
>> From: Annette M Cheever <acheever at ecn.purdue.edu>
>> Date: January 23, 2007 8:35:06 AM EST
>> Subject: Nano Seminar: Placidus Amama INAC Postdoctoral Fellow  
>> BNC, Purdue, 1/25/07 @ 10:30 AM, BRK 1001 (Dendrimer-Templated  
>> Catalyst for Controlled Growth of Single-Wall Carbon Nanotubes by  
>> Plasma-Enhanced CVD)
>>
>> “Dendrimer-Templated Catalyst for Controlled Growth of
>> Single-Wall Carbon Nanotubes by Plasma-Enhanced CVD”
>>
>> Thursday, January 25, 2007
>> 10:30 AM
>> Birck Nanotechnology Building, Room 1001
>>
>> Placidus Amama
>> INAC Postdoctoral Fellow
>> Birck Nanotechnology Center
>>
>> Carbon nanotubes (CNTs) are an important class of materials with  
>> several technological applications because they possess  
>> unparalleled properties in terms of ballistic electrical  
>> conductivity, thermal conductivity, tensile strength, and  
>> sensitivity to chemical and biological agents. To exploit these  
>> properties in functional devices, a major barrier that must be  
>> addressed is the ability to control important properties such as  
>> diameter, chirality, quality, density, and alignment. There is  
>> also the need to reduce the growth temperatures of CNTs (below 400° 
>> C) to enable growth on a variety of sensitive, pre-functionalized  
>> substrates, thereby making the growth process compatible with  
>> current nanofabrication technology. This talk focuses on the  
>> development of a suitable catalytic template for the controlled  
>> growth of single-wall carbon nanotubes (SWNTs) by plasma-enhanced  
>> CVD. An amine-terminated fourth-generation poly (amidoamine)  
>> (PAMAM) dendrimer with numerous reactive functional groups has  
>> been used as carriers to deliver nearly monodispersed Fe2O3  
>> nanoparticles (3.2 ±1nm) on different substrates. Microwave PECVD  
>> growth with these Fe2O3 nanoparticles supported on Al2O3  
>> substrates and annealed in an N2 ambient result in enhanced SWNT  
>> selectivity, quality and diameter uniformity. The application of  
>> dc bias voltage during SWNT growth seems to selectively remove  
>> amorphous carbon and metallic SWNTs, leaving mainly large-diameter  
>> semi-conducting SWNTs. Using these catalyst nanoparticles; a  
>> shielded growth approach has been developed for the growth of CNTs  
>> at low temperatures (200-400°C). Postmortem characterization of  
>> the catalytic template by XPS has provided insights into the  
>> growth mechanism of CNTs.
>>
>> Placidus Amama received his Ph.D. in Environmental Engineering  
>> from Yokohama National University, Japan. He is currently an INAC  
>> postdoctoral fellow working with Prof. Sands and Prof. Fisher.  
>> Earlier, he was a postdoctoral researcher at the Department of  
>> Chemical Engineering, Yale University. His research interests  
>> include heterogeneous catalysis, carbon nanotubes and  
>> nanostructured materials, nanotube processing and device fabrication.
>>
>> SPONSORED BY:
>> Birck Nanotechnology Center, Bindley Bioscience Center, Discovery  
>> Park, The NASA Institute for Nanoelectronics and Computing, The  
>> Network for Computational Nanotechnology, VEECO, NCN Student  
>> Leadership Council, Department of Chemistry, Department of  
>> Physics, School of Chemical Engineering, School of Electrical and  
>> Computer Engineering, School of Mechanical Engineering
>