Inkjet printing of electrically conductive patterns of carbon nanotubes

Commercial Desktop inkjet printing is a cost effective and scalable deposition method to investigate the behavior of the electrically conductive patterns of multi-walled carbon nanotube (MWCNT). MWCNTs grown by catalytic chemical vapor deposition (CCVD)are chemically modified to make the nanotube dispersible in water, and in turn the aqueous dispersion is dispensed on various substrates. The inductive behavior is explained by the curved nanotube, which can be considered as tiny coils being randomly oriented and connected on the surface. The inductances is more pronounced on paper than on plastic surfaces, since the deposited nanotube wrap around the microscopic paper fibers. The shift of impedance resonance towards the higher frequencies with an increased print number explains the vanishing inductive transport for the CNT deposits of higher surface density. The resistance values of the printed patterns varies with the ambient air quality during the course of data acquisition. With proper optimization of the printing parameters, such as improved substrate-alignment accuracy and ink rhelogy, and increased nanotube concentration, the method becomes a competitive technology for fabricating low-cost CNT devices.