Plasma-assisted purification of nanodiamonds and their application for direct writing of a high purity nanodiamond pattern

In this paper, we demonstrate a new approach for purifying nanodiamonds using an atmospheric-pressure plasma jet. Oxygen gas is continuously dissociated in the plasma jet and generates reactive oxygen, which plays a key role in removing non-diamond carbon, including graphite and amorphous carbon. The purification process was evaluated by UV-Raman (325 nm) and X-ray photoelectron spectroscopy. This technique was applied to create a high purity nanodiamond pattern in the polymeric system of polyvinyl alcohol (PVA) and nanodiamonds using a localized plasma jet. Overall, the plasma-assisted purification of nanodiamonds enabled to the fabrication of patterns with low electrical conductivity and high thermal conductivity. [Display omitted]