Comparison of dispersion methods of multi-walled carbon nanotubes in titanium oxide

Abstract

In this study, optimum homogeneous dispersion of multiwall carbon nanotubes (MWCNTs) in titanium oxide were examined using two different dispersion techniques with the aim of determining the milling parameters of the dispersion. The techniques were based on dry milling using high energy ball milling (HEBM) and ultrasonication probe/tip method assisted with HEBM (uHEBM). The HEBM technique was conducted at a milling speed of 100 rpm for 6 and 9 h and uHEBM method was ultrasonicated for 15 min and additional 5 min stirring time using a magnetic stirrer to homogenously mix MWCNT/TiO2 then slurry was milled at same parameters. The dispersibilty and structural features of the MWCNTs in TiO2 was assessed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and X-ray diffraction (XRD) to understand the uniformity of the dispersion. The morphologies results for both SEM and TEM showed that when HEBM technique was employed the MWCNTs were detangled to a certain extent especially at 9 h which proposes that the most effect technique for dispersion of MWCNTS is dry milling of HEBM than uHEBM. However, this could results to damage of MWCNTs therefore further analysis of structural integrity showed there was minimal structure damage due to lower speed and there were no interfacial reaction that occurred.