Transfer printing of submicrometer patterns of aligned carbon nanotubes onto functionalized electrodes

Aligned submicrometer patterns of acid-treated carbon nanotubes (CNT) on polydimethylsiloxane (PDMS) by transfer printing onto non-flat, patterned gold (Au) electrodes modified with a self-assembled monolayer (SAM) of 11-amino-1-undecanethiol are described. The process involves placing a submicrometer-channeled hydrophilized PDMS mold on a flat PDMS substrate and making conformal contact with the surface of the substrate. The patterned Au electrode surface was functionalized with an 11-amino-1-undecanethiol SAM. The SWNTs were treated with nitric acid to produce carboxyl groups on their surfaces and ends. The process realizes a horizontal alignment of the SWNT bundles on patterned Au substrates and a quick transfer, which makes it feasible for use in industrial production. The SWNTs alignment on the patterned Au electrode surface can be controlled by adjusting the suspension concentration and dosage.