Direct growth of three-dimensional multicomponent micropatterns of vertically aligned single-walled carbon nanotubes interposed with their multi-walled counterparts on Al-activated iron substrates

Vertically aligned single-walled carbon nanotubes (VA-SWNTs) have been synthesized by an Al-activated plasma-enhanced chemical vapor deposition (PECVD) method. On this basis, we have developed a facile but effective method for direct growth of multicomponent micropatterns of VA-SWNTs interposed within the patterned areas surrounded by vertically aligned multi-walled carbon nanotubes (VA-MWNTs) onto an Al-activated iron substrate. The Al-activated iron substrate was prepared by region-selectively depositing an Al thin layer on either an Fe-coated substrate or a commercially available iron foil. This simple approach allows for an effective integration of various aligned carbon nanotubes with different electronic characteristics into multifunctional materials and devices.