The method reported here on the direct growth of aligned
CNTs on the stainless steel foil is superior in various respects
compared to other techniques reported before.12-16 For example,
when compared with the PECVD14 method where multiple
pretreatment steps of stainless steel were involved, the present
method has only one pretreatment step, and it is very easy to
execute. Also, the present method may be economically scaled up
to large-scale production, and the alignment and density of
CNTs could readily be controlled compared to MPCVD12 and
the diffusion flame synthesis method.15,16 There is no need for
the catalyst preparation step since the catalyst is directly sent
along with the carbon source into the CVD furnace. This method
gives a higher yield of CNTs with growth rates exceeding 10
µm/min compared to the MPCVD method.12 The stainless steel
foil utilized is only 25 µm thick and is very flexible to be cut
into any size and shape with regular scissors. It can be used to
make sturdy and light-weight electrodes for field emission and
electrochemical applications.