First results of the surface modification of multiwall carbon nanotubes by a hollow cathode discharge

Since the discovery of carbon nanotubes (CNTs), there has been great interest in finding ways to functionalize them effectively. Cold plasma treatment of a material can graft - in a short time and with high yield - a wide range of chemical functions to the CNT surface, greatly modifying its reactivity. In this work, we present the results of the first trials performed with a special plasma reactor that can be used to functionalize larger amounts of CNTs. The reactor is a homemade, rotating, cylindrical, hollow cathode involving a fixed magnetron setup. The magnetron configuration ensures a very high plasma density. Two different gas discharges were used: nitrogen and allylamin. The plasma treatment effects were investigated by Scanning and (High Resolution) Transmission Electron Microscopy. The treated surfaces were also analysed by x-ray photoelectron spectroscopy and nuclear reaction analysis to evaluate the influence of the plasma treatment time and quantity of CNTs loaded in the hollow cathode on the nitrogen concentration. Nitrogen incorporation of up to 12% and CNTs wrapping of 20. nm thick Plasma Polymer Allylamin was achieved in 90. s. © 2010 Elsevier B.V.