Large-area fluidic assembly of single-walled carbon nanotubes through dip-coating and directional evaporation

Abstract

We present a simple and scalable fluidic-assembly approach, in which bundles of single-walled carbon nanotubes (SWCNTs) are selectively aligned and deposited by directionally controlled dip-coating and solvent evaporation processes. The patterned surface with alternating regions of hydrophobic polydimethyl siloxane (PDMS) (height ~ 100 nm) strips and hydrophilic SiO 2 substrate was withdrawn vertically at a constant speed (~3 mm/min) from a solution bath containing SWCNTs (~0.1 mg/ml), allowing for directional evaporation and subsequent selective deposition of nanotube bundles along the edges of horizontally aligned PDMS strips. In addition, the fluidic assembly was applied to fabricate a field effect transistor (FET) with highly oriented SWCNTs, which demonstrate significantly higher current density as well as high turn-off ratio (T/O ratio ~ 100) as compared to that with randomly distributed carbon nanotube bundles (T/O ratio ~ <10).

Carbon Nanotube Films for Energy Applications

“…Once such CNT dispersion is obtained, it can be deposited onto a substrate in many ways. Among the simplest and oldest methods of CNT film formation is called dip coating (Figure 1a) [32][33][34][35][36]. In this approach, a substrate is immersed in a reservoir containing a CNT dispersion, and then the substrate is withdrawn for drying.…”

Feasibility Study of Dielectric Barrier Discharge Jet-Patterned Perfluorodecyltrichlorosilane-Coated Paper for Biochemical Diagnosis

“…[14][15][16] A paper-based device often requires surface coating and patterning to achieve liquid routing, mixing, and confinement. Common methods for this purpose include flexographic printing, 7 inkjet printing, 17 wax printing, 18,19 dip coating, 20 Teflon flow through synthesis, 21,22 and polymer deposition modification. 23,24 Another method is alkylsilane self-assembling and patterning.…”