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These are amorphousagglomerated sootnanoparticles collected on aninert SiC fiber placed in a flame

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Combustion products

Substrate

Catalyst chemistry and heatand mass transport

Nanofibrous carbon,

containing CNTs and CNFs

Nanofibrous carbon, containingCNTs and CNFs

Gas phase chemistry& transport Heat & mass transfer

Catalyst grain formation

Heat & mass transfer

Nanostructure formation

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The only model to include

catalysis, transport and

ambient conditions, suchas combustion.

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Zhang & Smith, J. Catal., 2005Bower et al., App. Phys. Lett., 2000

Bronikowski, Carbon, 2006

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CNT length versus time for CVDsynthesis at different

temperatures using Co as thecatalyst at a 5 Torr C2H2 partialpressure.

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!%##"('

''&""$

!"

"

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)$%&

)$'##

*!

+!

%##(

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!

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Naturally occurring superhydrophobic surfaces have microscalefeatures with nanoscale asperities.

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Naha, S., Sen, S. and Puri, I. K. Carbon 45, 2007.

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Flame Si disc(substrate)

Deposition zone due to flame

Air Fuel(Ethylene)

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Naha, S., Sen, S. and Puri, I. K. Carbon 45, 2007

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Cassie-Baxter State Water droplet sits partly on the solid

surface and partly on air trapped within

the asperities.

Contact angle results from contact ofwater with both air and the solidsubstrate.

Droplet tends to roll of easily.

Cannon, Andrew H. Wikipedia, the Free Encyclopedia. Web. 17 July

2010

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Disc center 45 mm from disc center

SEM images of nanopearls

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TEM images of nanopearls

Nanobead region Sooty region

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Nanobead region Sooty region

X-ray Photoelectric Spectroscopy (XPS) analysis using Mg source (anode)

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*Y. Zhou, B. Wang, X. Song, E. Li, G. Li, S. Zhao, H. Yan, Appl. Surf. Sci. 253 (2006) 2690-2694.

*&"+'.

%

"' *((.

"

#)*")+.$!

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0

5000

10000

15000

20000

25000

20030040050060070080090010001100

Binding Energy (eV)

Intensity

(arbitrary

units)

Nanobead Region Sooty Region

C1s

O1sO KVV

C KLL

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"!

#

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$"$$"$$"$$!

!)+#***%**,!)'('

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&

!"%')+#

"(&*#Ethylene

AirAir

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"#'+'&$&()

"#'++$

#'&!*&)

$

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!!"! *))"$%'"(

!"!"#"%! "!!!$

!'( '(*++)!+!#!#""

&

"$'"!"( !$'(

'(

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!

h = 2 mm

= 34.15

h = 4 mm

=131.90

h = 6 mm

=126.80

h = 8 mm

=141.60

Coverage volumeincreases with height

No discernible carbonnanostructure deposit at2mm height and surfaceis hydrophilic

Spongy nanobeadclusters appear at heightsof 4 mm and above,leading to high contactangles

Mean nanoparticlesize at this stage is13 nm

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!

$$ !$"

#!

"

Stainless Steel Mesh (h = 10mm)

Stainless Steel Foil (h = 10mm)

Uncoated Silicon Wafer (h = 10mm)

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!

"#

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