Gas-liquid interfacial discharge plasmas are generated between ionic liquid and stainless steel electrodes, where a pulse power source is used to operate the discharges. The temporal evolution of the plasma is investigated as well as the spatial distribution of the plasma. The positive pulse discharge plasma can not be detected by a double Langmuir probe, which is attributed to the fast diffusion of the plasma toward the chamber wall due to its high positive potential. On the other hand, the negative pulse discharge plasma parameters can be measured and the density decreases with increasing the distance away from the ionic liquid electrode. The plasma is mostly an after-glow discharge plasma since the plasma density gradually decreases after the discharge in a long period. In addition, we synthesize gold nanoparticle-DNA encapsulated single-walled carbon nanotubes by superimposing a DC voltage to the pulse voltage. (C) 2011 Elsevier B.V. All rights reserved.