Application of plasma-modified single-walled carbon nanohorns for PVPI slow release

Abstract

In this work, SWCNHs synthesized by gas-injected arc-in-water (GI-AIW) method have been modified by oxygen plasma for increasing their surface hydrophilicity. The effects of treatment parameters, which are irradiating time, pressure and electricity current on characteristics of plasma-treated SWCNHs was investigated and reported. It was found that oxygen plasma treatment enhanced hydrophilic property of SWCNHs. SWCNHs treated by oxygen plasma can be dispersed in deionized water for a long time period when compared with pristine SWCNHs. It is also reasonable to imply the presence of C=O, carboxylic group, on the surface of SWCNHs treated by oxygen plasma treatment would lead to a higher level of their dispersion. In addition, zeta potential analysis could confirm the stability of the plasma-treated SWCNHs. For examining slow releases behavior polyvinylpyrrolidone-iodine (PVPI) was impregnated onto the pristine and plasma-treated SWCNHs. It was found that plasma-treated SWCNHs can help reduce the desorption rate of PVPI, leading to its slow release because of functional groups. The pseudo 2nd order kinetic model could be fitted for estimating PVPI release.